Link updated

README.md

@@ -1,212 +1,48 @@
 # Splitter
 
-Splitter is a high‑performance command line tool for cutting one or more video files into equal or fixed‑length segments using multi‑threaded FFmpeg execution.
+Splitter is a high-performance command line tool for cutting one or more video files into equal or 
-It supports batch input, flexible duration formats, rotation, smart face/body‑aware cropping, ETA and speed reporting, and both rich and plain‑text terminal output.
+fixed‑length segments using multi‑threaded FFmpeg execution. It supports batch input, flexible 
+duration formats, rotation, smart face/body‑aware cropping, ETA and speed reporting, with nice GUI 
+or both rich and plain‑text terminal output.
 
-![Splitter](splitter.png)
+The intended primary use case is for content creators who need to split large video files into smaller 
+segments for platforms like TikTok, Instagram Reels, YouTube Shorts, or similar. The smart 
+cropping feature allows the tool to automatically detect and keep faces or bodies in the frame 
+when splitting, ensuring that important content is not cut off.
+
+Splitter uses cutting-edge body-detection CV models to analyze the video and determine optimal 
+cropping regions for each segment. Smooth tracking and gravitation bias ensure that the cropping remains
+stable and focused on the subject without excessive jitter or erratic movements. 
+The tool can also correct for rotation metadata to ensure proper orientation in the output segments.
+
+Splitter uses FFmpeg for the actual splitting and encoding, with multi-threading to maximize performance.
 
 ## Features
 
-- Multi‑threaded FFmpeg splitting for maximum throughput
+- Human face or body detection with smart cropping
+- Multi-threaded FFmpeg splitting for maximum throughput
 - Equal or fixed‑length segmentation
 - Batch input via file masks or list files
 - Smart cropping with face/body tracking
 - Rotation correction
 - ETA, speed, and progress display
 - FFmpeg passthrough for advanced control
-- [Potentially] Cross‑platform (.NET 10)
+- [Potentially] Cross-platform (.NET 10)
+
+## Screenshots
+
+### Command line interface
+![Splitter](splitter-cli/splitter.png)
+### Graphical user interface
+![Splitter UI](splitter-ui/screenshot.png)
 
 ## Requirements
 
 - FFmpeg and FFprobe available in system PATH
 - .NET 10 Runtime or newer
 
-If you want to update model:
+## More info
 
-- For face detection: [opencv_zoo/models/face_detection_yunet at main · opencv/opencv_zoo](https://github.com/opencv/opencv_zoo/tree/main/models/face_detection_yunet)
+[Command line tool](splitter-cli/README.md)
-- For body detection: [yolov8s.pt · Ultralytics/YOLOv8 at main](https://huggingface.co/Ultralytics/YOLOv8/blob/main/yolov8s.pt)
-
-To convert models from PyTorch to ONNX, you can use the following command:
-
-```python
-from ultralytics import YOLO
-
-model = YOLO("yolov8x.pt")
-model.export(format="onnx", opset=12, half=False)   # FP32 ONNX
-```
-
-## How It Works
-
-1. Reads total duration using ffprobe
-2. Parses target duration
-3. Computes number of segments
-4. If not forced, equalizes segment lengths
-5. Runs multiple FFmpeg processes in parallel
-6. Applies rotation, crop, and tracking if enabled
-7. Displays progress, ETA, and speed
-
-## Face Tracking vs Body Tracking
-
-Face tracking and body tracking serve different purposes, and Splitter supports both because each
-excels in different recording environments. When converting horizontal footage into vertical clips,
-the choice of detector determines how stable, reliable, and natural the automated camera motion will be.
-
-![Face vs Body Tracking](tracking.png)
-
-### Face Tracking Using UltraFace 320
-
-Splitter uses the UltraFace 320 ONNX model to perform lightweight, real‑time face detection on each
-frame of the input video. The detector produces bounding boxes for visible faces, and the tracking
-system maintains a stable, smoothed target region across time. This is achieved by combining per‑frame
-detections with temporal smoothing (EMA), dropout tolerance, and camera easing. The result is a
-continuous, stable crop window that follows the performer even when the face is partially occluded,
-briefly lost, or moving rapidly.
-
-During segmentation, the crop window is recalculated for every frame, ensuring that each output
-segment inherits the same smooth camera motion. This makes the vertical clips appear as if they
-were recorded with a dedicated portrait‑oriented camera operator. The UltraFace 320 model is
-fast enough to run alongside multi‑threaded FFmpeg splitting without becoming a bottleneck,
-making it suitable for long recordings and batch processing.
-
-### Benefits of Full‑Body Detection Using YOLOv8s for Live Gig Recordings
-
-When recording concerts or live gigs, performers often move unpredictably, turn away from the
-camera, or become partially obscured by lighting, instruments, or stage effects.
-Full‑body detection using a YOLOv8s ONNX model provides a more reliable tracking anchor than
-face detection alone. Because YOLOv8s can detect the entire human silhouette, the tracker
-maintains stable framing even when the face is not visible, when the performer is far from
-the camera, or when stage lighting makes facial features hard to detect. This produces vertical
-clips that feel intentional and professionally framed, with fewer sudden jumps or lost‑tracking
-moments. For creators converting horizontal gig footage into short vertical clips for YouTube
-Shorts or TikTok, body‑based tracking significantly improves consistency, reduces manual editing,
-and preserves the energy and motion of the performance.
-
-### Automated Camera Control
-
-Splitter includes an automated camera control system that simulates the behavior of a virtual
-camera operator when generating vertical crops from horizontal footage. The goal is to maintain
-smooth, intentional framing around the tracked subject, even when detections are noisy, intermittent,
-or temporarily lost.
-
-The controller receives object detections (face or body) and converts them into a stable crop
-window using a combination of Kalman filtering, exponential smoothing, dropout tolerance,
-and a three‑state tracking model. The Kalman filter provides predictive motion smoothing,
-while the EMA factor blends the predicted position with the previous camera center to avoid jitter.
-The camera easing value controls how quickly the virtual camera follows the subject, producing
-natural‑looking motion rather than abrupt jumps.
-
-When detections disappear, the controller enters one of two fallback modes. In LostFreeze mode,
-the camera holds its last known position for a configurable number of frames, preventing sudden
-jumps during brief occlusions. If the subject remains lost beyond that threshold, the controller
-transitions to LostDrift mode, slowly drifting the camera back toward a neutral center position.
-This prevents the crop from drifting off‑screen and ensures that the output remains usable even
-when tracking fails. All positions are clamped to valid bounds, guaranteeing that the crop window
-never leaves the video frame.
-
-### Automatic rotation detection
-
-The rotation‑estimation method is based on analyzing the distribution of gradient orientations within 
-a video frame. After converting the frame to grayscale, the algorithm computes horizontal and vertical 
-image gradients using Sobel operators and derives per‑pixel gradient magnitudes and orientations. 
-These orientations are folded into the range [0, 180) and accumulated into a fixed‑size, 
-magnitude‑weighted histogram. The histogram represents the structural edge distribution of the frame, 
-independent of brightness fluctuations or local lighting artifacts. By comparing the total gradient
-energy concentrated near 0 degrees (vertical edges) with the energy near 90 degrees (horizontal edges), 
-the method determines whether the frame is more consistent with an upright or sideways orientation.
-
-This approach is designed for environments where brightness‑based cues are unreliable, such as
-live concerts with strobe lights, LED walls, haze, and crowd movement. It relies solely on geometric 
-edge structure, which remains stable even under extreme lighting variation. The implementation is 
-optimized for high‑throughput video processing: all intermediate Mats, buffers, and histograms are 
-preallocated, and pixel data is accessed directly through pointers to avoid per‑frame memory 
-allocation. The method is intentionally biased toward the upright orientation, returning a sideways
-classification only when the horizontal‑edge energy significantly exceeds the vertical‑edge energy.
-
-## Usage
-
-```
-splitter [<input.mp4> ...] [options] [--] <ffmpeg passthrough>
-```
-
-Inputs may be provided directly, via `--file=...`, or using file masks such as `videos/*.mp4`.
-
-
-## Options
-
-Below is a clean, ASCII‑only **options table** version of your content.
-All option names are preserved exactly, and descriptions are consolidated for clarity.
-
----
-
-## Options
-
-| Option | Description |
-|--------|-------------|
-| **--out=<folder>** | Output folder for generated segments. Default: `<input folder>/Splitter`. |
-| **--file=<path>** | Input file list or file mask. If omitted, the first non‑option argument is used as input. Examples: `--file=videos/*.mp4`, `--file=file_list.txt`. |
-| **--mask=<pattern>** | Custom output filename pattern. Default: `[NAME]_seg[NN].[EXT]`. Supports `[NAME]`, `[N]`, `[NN]`, `[NNN]`, `[NNNN]`, `[EXT]`. Example: `--mask="[NAME]_[NNNN].mp4"`. |
-| **--duration=<value>** | Override target segment duration. Formats: `Ns`, `NmMs`, `N`. Examples: `--duration=90s`, `--duration=2m30s`, `--duration=45`. Without `--force`: max 58 seconds, equalized across segments. |
-| **--force** | Use the duration exactly as provided. Last segment may be shorter. |
-| **--rotate=<degrees>** | Rotate video by 90, 180, or 270 degrees. Useful for correcting orientation metadata. |
-| **--rotate-auto** | Use automatic rotation detection. |
-| **--estimate** | Print calculated segment information and exit. No splitting is performed. |
-| **--crop[=<w:h>]** | Crop video to a target width and height with face/body tracking. Default: 607x1080. Ideal for Shorts, TikTok, Reels. |
-| **--detect=<name>** | Object detector for tracking. Values: `face` (UltraFace), `body` (YoloOnnx, default), `none` (center crop). |
-| **--gravitate=<x:y>** | Bias the crop window toward a normalized point in the frame. Example: `--gravitate=0.2:0.5`. |
-| **--text** | Use plain‑text logging instead of the rich terminal UI. |
-| **--single-thread** | Disable parallel FFmpeg execution. Useful for debugging or low‑resource systems. |
-| **--debug** | Show debug overlay during tracking. No cropping performed, but crop region shown. |
-| **-p:<name>=<value>** | Set custom parameters for the object detector. Example: `-p:confidence=0.5`. Defaults: DropoutToleranceFrames=20, EmaFactor=0.65, CameraEasing=0.03, LostFreezeFrames=60. |
-
-## FFmpeg Passthrough
-
-Anything after `--` is passed directly to FFmpeg.
-
-Example:
-```
-splitter video.mp4 --force --duration=45 -- -an -sn
-```
-
-## Input and Output Behavior
-
-- `input.mp4` may be a file mask (`videos/*.mp4`)
-- Output filenames follow the `--mask` pattern
-- Output folder defaults to `<input folder>/Splitter` unless overridden
-
-## Examples
-
-Split into equal 60‑second segments:
-```
-splitter vertical-video.mp4
-```
-
-Split into equal 90‑second segments:
-```
-splitter vertical-video.mp4 --duration=90s
-```
-
-Custom naming:
-```
-splitter vertical-video.mp4 --duration=2m30s --mask="[NAME]_[NNNN].mp4"
-```
-
-Estimate only:
-```
-splitter vertical-video.mp4 --estimate
-```
-
-Fixed 45‑second segments with passthrough:
-```
-splitter vertical-video.mp4 --force --duration=45 -- -an -sn
-```
-
-Smart crop for Shorts:
-```
-splitter horizontal-video.mp4 --out=Cropped/ --crop
-```
-
-Batch processing with body tracking:
-```
-splitter --file=file_names.txt --out=Cropped/ --crop --detect=body
-```
 
+[GUI tool](Splitter-UI/README.md)

Splitter-UI/App.axaml

@@ -0,0 +1,23 @@
+<Application xmlns="https://github.com/avaloniaui"
+             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+             x:Class="Splitter_UI.App"
+             xmlns:local="using:Splitter_UI"
+             xmlns:cnv="using:Splitter_UI.Converters"
+             RequestedThemeVariant="Default">
+             <!-- "Default" ThemeVariant follows system theme variant. "Dark" or "Light" are other available options. -->
+
+    <Application.DataTemplates>
+        <local:ViewLocator/>
+    </Application.DataTemplates>
+  
+    <Application.Resources>
+        <cnv:ActionToIconConverter x:Key="ActionToIconConverter"/>
+         <FontFamily x:Key="FontAwesome">avares://Splitter-UI/Assets/Fonts/Font Awesome 7 Free-Solid-900.otf#Font Awesome 7 Free Solid</FontFamily>
+    </Application.Resources>
+
+    <Application.Styles>
+        <FluentTheme/>
+        <StyleInclude Source="avares://Avalonia.Controls.DataGrid/Themes/Fluent.xaml"/>
+    </Application.Styles>
+
+</Application>

Splitter-UI/App.axaml.cs

@@ -0,0 +1,39 @@
+using Avalonia;
+using Avalonia.Controls.ApplicationLifetimes;
+using Avalonia.Markup.Xaml;
+using Microsoft.Extensions.DependencyInjection;
+using Splitter_UI.Views;
+
+namespace Splitter_UI;
+
+public partial class App : Application
+{
+    private readonly ServiceProvider _provider = null!;
+
+    public App() { }
+
+    public App(ServiceProvider provider)
+    {
+        _provider = provider;
+    }
+
+    public override void Initialize()
+    {
+        AvaloniaXamlLoader.Load(this);
+    }
+
+    public override void OnFrameworkInitializationCompleted()
+    {
+        if (ApplicationLifetime is IClassicDesktopStyleApplicationLifetime desktop)
+        {
+            var vm = _provider.GetRequiredService<MainViewModel>();
+
+            desktop.MainWindow = new MainWindow
+            {
+                DataContext = vm
+            };
+        }
+
+        base.OnFrameworkInitializationCompleted();
+    }
+}

Splitter-UI/Assets/splitter.svg

@@ -0,0 +1,100 @@
+<svg width="256" height="256" viewBox="0 0 256 256" xmlns="http://www.w3.org/2000/svg">
+
+  <!-- Background -->
+  <defs>
+    <linearGradient id="bgGrad" x1="0" y1="0" x2="1" y2="1">
+      <stop offset="0%" stop-color="#111827"/>
+      <stop offset="100%" stop-color="#020617"/>
+    </linearGradient>
+
+    <linearGradient id="accentGrad" x1="0" y1="0" x2="1" y2="1">
+      <stop offset="0%" stop-color="#22C55E"/>
+      <stop offset="100%" stop-color="#0EA5E9"/>
+    </linearGradient>
+
+    <linearGradient id="videoGrad" x1="0" y1="0" x2="1" y2="1">
+      <stop offset="0%" stop-color="#F97316"/>
+      <stop offset="100%" stop-color="#EC4899"/>
+    </linearGradient>
+
+    <linearGradient id="cropGrad" x1="0" y1="0" x2="1" y2="1">
+      <stop offset="0%" stop-color="#38BDF8"/>
+      <stop offset="100%" stop-color="#6366F1"/>
+    </linearGradient>
+  </defs>
+
+  <rect x="0" y="0" width="256" height="256" rx="56" fill="url(#bgGrad)" />
+
+  <!-- Split timeline bar -->
+  <g transform="translate(32,188)">
+    <rect x="0" y="-10" width="192" height="20" rx="10" fill="#020617" />
+    <rect x="0" y="-10" width="192" height="20" rx="10" fill="url(#accentGrad)" opacity="0.18" />
+
+    <!-- Segment markers -->
+    <rect x="32"  y="-14" width="3" height="28" rx="1.5" fill="#FACC15" />
+    <rect x="80"  y="-14" width="3" height="28" rx="1.5" fill="#FACC15" />
+    <rect x="128" y="-14" width="3" height="28" rx="1.5" fill="#FACC15" />
+    <rect x="176" y="-14" width="3" height="28" rx="1.5" fill="#FACC15" />
+  </g>
+
+  <!-- Video tile (left) -->
+  <g transform="translate(26,52)">
+    <rect x="0" y="0" width="96" height="72" rx="12" fill="#020617" />
+    <rect x="0" y="0" width="96" height="72" rx="12" fill="url(#videoGrad)" opacity="0.9" />
+
+    <!-- Play triangle -->
+    <polygon points="38,22 64,36 38,50" fill="#F9FAFB" opacity="0.9" />
+
+    <!-- Small split indicator -->
+    <rect x="12" y="60" width="72" height="4" rx="2" fill="#111827" opacity="0.7" />
+    <rect x="36" y="58" width="2" height="8" rx="1" fill="#FACC15" />
+    <rect x="60" y="58" width="2" height="8" rx="1" fill="#FACC15" />
+  </g>
+
+  <!-- Video tile (right, shifted to suggest batch / multi-thread) -->
+  <g transform="translate(134,40)">
+    <rect x="0" y="0" width="96" height="72" rx="12" fill="#020617" />
+    <rect x="0" y="0" width="96" height="72" rx="12" fill="url(#videoGrad)" opacity="0.75" />
+
+    <!-- Play triangle -->
+    <polygon points="38,22 64,36 38,50" fill="#F9FAFB" opacity="0.85" />
+
+    <!-- Small split indicator -->
+    <rect x="12" y="60" width="72" height="4" rx="2" fill="#111827" opacity="0.7" />
+    <rect x="30" y="58" width="2" height="8" rx="1" fill="#FACC15" />
+    <rect x="54" y="58" width="2" height="8" rx="1" fill="#FACC15" />
+    <rect x="78" y="58" width="2" height="8" rx="1" fill="#FACC15" />
+  </g>
+
+  <!-- Smart crop frame with body/face hint -->
+  <g transform="translate(76,86)">
+    <!-- Outer crop frame -->
+    <rect x="0" y="0" width="104" height="104" rx="18" fill="#020617" opacity="0.9" />
+    <rect x="0" y="0" width="104" height="104" rx="18" fill="url(#cropGrad)" opacity="0.25" />
+
+    <!-- Corner crop brackets -->
+    <path d="M10 30 V14 A4 4 0 0 1 14 10 H30" stroke="#E5E7EB" stroke-width="3" stroke-linecap="round" fill="none" />
+    <path d="M74 10 H90 A4 4 0 0 1 94 14 V30" stroke="#E5E7EB" stroke-width="3" stroke-linecap="round" fill="none" />
+    <path d="M10 74 V90 A4 4 0 0 0 14 94 H30" stroke="#E5E7EB" stroke-width="3" stroke-linecap="round" fill="none" />
+    <path d="M74 94 H90 A4 4 0 0 0 94 90 V74" stroke="#E5E7EB" stroke-width="3" stroke-linecap="round" fill="none" />
+
+    <!-- Body / face glyph -->
+    <!-- Head -->
+    <circle cx="52" cy="36" r="11" fill="#F9FAFB" />
+    <!-- Torso -->
+    <path d="M32 72 C34 56 42 48 52 48 C62 48 70 56 72 72 Z"
+          fill="#F9FAFB" />
+
+    <!-- Gravitation / tracking bias arc -->
+    <path d="M30 82 A24 24 0 0 0 74 82"
+          stroke="url(#accentGrad)" stroke-width="3" stroke-linecap="round" fill="none" opacity="0.9" />
+  </g>
+
+  <!-- Subtle multi-thread / performance hint (three vertical bars) -->
+  <g transform="translate(210,188)">
+    <rect x="-10" y="-18" width="4" height="24" rx="2" fill="#22C55E" opacity="0.9" />
+    <rect x="-2"  y="-22" width="4" height="28" rx="2" fill="#4ADE80" opacity="0.9" />
+    <rect x="6"   y="-16" width="4" height="22" rx="2" fill="#16A34A" opacity="0.9" />
+  </g>
+
+</svg>

Splitter-UI/Converters/ActionToIconConverter.cs

@@ -0,0 +1,23 @@
+using System.Globalization;
+using Avalonia.Data.Converters;
+
+namespace Splitter_UI.Converters;
+
+public sealed class ActionToIconConverter : IValueConverter
+{
+    public object? Convert(object? value, Type targetType, object? parameter, CultureInfo culture)
+    {
+        if (value == null)
+            return null;
+
+        var p = System.Convert.ToInt32(value);
+        
+        return p == 0 
+            ? "\uf125" // FA7 crop
+            : "\uf2f1" // FA7 rotate
+            ;
+    }
+
+    public object? ConvertBack(object? value, Type targetType, object? parameter, CultureInfo culture)
+        => throw new NotSupportedException();
+}

Splitter-UI/Converters/BoolInvertConverter.cs

@@ -0,0 +1,15 @@
+using System.Globalization;
+using Avalonia.Data.Converters;
+
+namespace Splitter_UI.Converters;
+
+public sealed class BoolInvertConverter : IValueConverter
+{
+    public static readonly BoolInvertConverter Instance = new();
+
+    public object? Convert(object? value, Type targetType, object? parameter, CultureInfo culture)
+        => value is bool b ? !b : value;
+
+    public object? ConvertBack(object? value, Type targetType, object? parameter, CultureInfo culture)
+        => value is bool b ? !b : value;
+}

Splitter-UI/Converters/ConsoleColorToBrushConverter.cs

@@ -0,0 +1,39 @@
+using Avalonia.Data.Converters;
+using Avalonia.Media;
+using System.Globalization;
+
+namespace Splitter_UI.Converters;
+
+public sealed class ConsoleColorToBrushConverter : IValueConverter
+{
+    public object? Convert(object? value, Type targetType, object? parameter, CultureInfo culture)
+    {
+        if (value is ConsoleColor c)
+            return new SolidColorBrush(ToColor(c));
+
+        return Brushes.White;
+    }
+
+    private static Color ToColor(ConsoleColor c) =>
+        c switch
+        {
+            ConsoleColor.Black       => Colors.Black,
+            ConsoleColor.DarkBlue    => Colors.DarkBlue,
+            ConsoleColor.DarkGreen   => Colors.DarkGreen,
+            ConsoleColor.DarkCyan    => Colors.DarkCyan,
+            ConsoleColor.DarkRed     => Colors.DarkRed,
+            ConsoleColor.DarkMagenta => Colors.DarkMagenta,
+            ConsoleColor.DarkYellow  => Colors.Olive,
+            ConsoleColor.Gray        => Colors.Gray,
+            ConsoleColor.DarkGray    => Colors.DarkGray,
+            ConsoleColor.Blue        => Colors.Blue,
+            ConsoleColor.Green       => Colors.Green,
+            ConsoleColor.Cyan        => Colors.Cyan,
+            ConsoleColor.Red         => Colors.Red,
+            ConsoleColor.Magenta     => Colors.Magenta,
+            ConsoleColor.Yellow      => Colors.Yellow,
+            ConsoleColor.White       => Colors.White,
+            _                        => Colors.White
+        };
+    public object? ConvertBack(object? value, Type targetType, object? parameter, CultureInfo culture) => throw new NotImplementedException();
+}

Splitter-UI/Converters/RotationAngleToIconConverter.cs

@@ -0,0 +1,21 @@
+using System.Globalization;
+using Avalonia.Data.Converters;
+
+namespace Splitter_UI.Converters;
+
+public sealed class RotationAngleToIconConverter : IValueConverter
+{
+    public object? Convert(object? value, Type targetType, object? parameter, CultureInfo culture)
+    {
+        return value switch
+        {
+            90  => "\uf2f9",  // FA7 (fa-rotate-left  / fa-arrow-rotate-left  / fa-undo)
+            180 => "\uf2f1",  // FA7 (fa-sync-alt)
+            270 => "\uf2ea",  // FA7 (fa-rotate-right / fa-arrow-rotate-right / fa-redo)
+            _   => null
+        };
+    }
+
+    public object? ConvertBack(object? value, Type targetType, object? parameter, CultureInfo culture)
+        => throw new NotSupportedException();
+}

Splitter-UI/Converters/ZeroToBoolConverter.cs

@@ -0,0 +1,13 @@
+using System.Globalization;
+using Avalonia.Data.Converters;
+
+namespace Splitter_UI.Converters;
+
+public sealed class ZeroToBoolConverter : IValueConverter
+{
+    public object? Convert(object? value, Type targetType, object? parameter, CultureInfo culture)
+        => (value is int i && i == 0);
+
+    public object? ConvertBack(object? value, Type targetType, object? parameter, CultureInfo culture)
+        => throw new NotSupportedException();
+}

Splitter-UI/GlobalUsing.cs

@@ -0,0 +1,16 @@
+global using System;
+global using System.Collections.Generic;
+global using System.Threading.Tasks;
+
+global using OpenCvSharp;
+global using Size = Avalonia.Size;
+global using Rect = Avalonia.Rect;
+
+global using splitter;
+global using splitter.tui;
+global using splitter.algo;
+global using splitter.probe;
+
+global using Splitter_UI.Models;
+global using Splitter_UI.Services;
+global using Splitter_UI.ViewModels;

Splitter-UI/Models/ParameterEntry.cs

@@ -0,0 +1,15 @@
+using CommunityToolkit.Mvvm.ComponentModel;
+
+namespace Splitter_UI.Models;
+
+public partial class ParameterEntry : ObservableObject
+{
+    public string Key { get; }
+    [ObservableProperty] private string _value;
+
+    public ParameterEntry(string key, string value)
+    {
+        Key = key;
+        Value = value;
+    }
+}

Splitter-UI/Models/PreviewData.cs

@@ -0,0 +1,18 @@
+namespace Splitter_UI.Models;
+
+public class PreviewData
+{
+    public Avalonia.Media.Imaging.Bitmap? Frame          { get; }
+    public IReadOnlyList<OpenCvSharp.Rect> DetectedBoxes { get; }
+    public Rect? CropRect                                { get; }
+    public Point2f GravitateTo                           { get; }
+
+    public PreviewData(Avalonia.Media.Imaging.Bitmap? frame, IReadOnlyList<OpenCvSharp.Rect> boxes, Rect? crop, Point2f gravitateTo)
+    {
+        Frame         = frame;
+        DetectedBoxes = boxes;
+        CropRect      = crop;
+        GravitateTo   = gravitateTo;
+    }
+
+}

Splitter-UI/Program.cs

@@ -0,0 +1,81 @@
+using Avalonia;
+using Avalonia.Media;
+using Microsoft.Extensions.DependencyInjection;
+
+namespace Splitter_UI;
+
+internal sealed class Program
+{
+    // Initialization code. Don't use any Avalonia, third-party APIs or any
+    // SynchronizationContext-reliant code before AppMain is called: things aren't initialized
+    // yet and stuff might break.
+    [STAThread]
+    public static void Main(string[] args)
+    {
+        var services = ConfigureServices();
+        var provider = services.BuildServiceProvider();
+
+        BuildAvaloniaApp(provider)
+            .StartWithClassicDesktopLifetime(args);
+    }
+
+    private static ServiceCollection ConfigureServices()
+    {
+        var services = new ServiceCollection();
+
+        var logPaveVM = new LogPaneViewModel();
+        // ViewModels
+        services.AddTransient<MainViewModel>();
+        services.AddTransient<FileListViewModel>();
+        services.AddTransient<PreviewPaneViewModel>();
+        services.AddTransient<InspectorPaneViewModel>();
+        services.AddSingleton<StatusBarViewModel>();
+        services.AddSingleton<ProgressViewModel>();
+        services.AddSingleton<LogPaneViewModel>(logPaveVM);
+        services.AddSingleton<ILogService>(logPaveVM);
+
+        // splitter services
+        services.AddSingleton<UltraFaceDetector>();
+        services.AddSingleton<YoloOnnxObjectDetector>();
+        services.AddSingleton( x => new SingleThreadedDetector<UltraFaceDetector>(x.GetRequiredService<UltraFaceDetector>()) );
+        services.AddSingleton( x => new SingleThreadedDetector<YoloOnnxObjectDetector>(x.GetRequiredService<YoloOnnxObjectDetector>()));
+        services.AddSingleton<Func<string, IObjectDetector>>( x => detectorName =>
+        {
+            return detectorName switch
+            {
+                "face" => x.GetRequiredService<SingleThreadedDetector<UltraFaceDetector>>(),
+                "body" => x.GetRequiredService<SingleThreadedDetector<YoloOnnxObjectDetector>>(),
+                _      => new DummyDetector()
+            };
+        });
+        services.AddSingleton<ILogger, GlobalLogger>();
+        services.AddSingleton<IJobProcessor, JobProcessor>();
+
+        // Domain services (your pipeline)
+        services.AddTransient<IFileProbeService,    FileProbeService>();
+        services.AddTransient<IThumbnailService,    ThumbnailService>();
+        services.AddSingleton<IAutoDecisionService, AutoDecisionService>();
+
+        services.AddSingleton<IFileJobFactory, FileJobFactory>();
+
+        return services;
+    }
+
+    // Avalonia configuration, don't remove; also used by visual designer.
+    public static AppBuilder BuildAvaloniaApp(ServiceProvider provider)
+        => AppBuilder.Configure<App>(() => new App(provider))
+            .UsePlatformDetect()
+            .With(new FontManagerOptions
+            {
+                FontFallbacks = new[]
+                {
+                    new FontFallback { FontFamily = new FontFamily("Font Awesome 7 Free") },
+                    new FontFallback { FontFamily = new FontFamily("Font Awesome 7 Free Solid") }
+                }
+            })
+#if DEBUG
+            .WithDeveloperTools()
+#endif
+            .WithInterFont()
+            .LogToTrace();
+}

Splitter-UI/README.md

@@ -0,0 +1,59 @@
+# Splitter-UI
+
+
+A compact, modern desktop front-end for Splitter (the high-performance FFmpeg-based video splitter). Built with Avalonia 12 and 
+targeting .NET 10, this project provides a native-feeling cross-platform UI to configure splitting jobs, preview smart 
+crops, and drive the Splitter CLI backend.
+
+## Overview
+
+Splitter-UI wraps the core Splitter pipeline (the referenced splitter-cli project) and exposes common workflow tasks 
+through an accessible interface: input selection, output naming, duration and crop controls, rotation options, detector settings, 
+and a job monitor with progress and ETA. For the full command-line feature set and the implementation rationale, see the 
+repository root README (../README.md).
+
+## Screenshots
+
+![Main window with job list and settings](screenshot.png)
+
+
+## Getting started
+
+Requirements: .NET 10 runtime and FFmpeg/FFprobe available on PATH. The UI references the splitter-cli project; 
+build the solution to ensure the CLI is available to the UI during development.
+
+To build and run locally:
+
+1. From the solution root run: dotnet build
+2. Start the UI project: dotnet run --project Splitter-UI
+
+## Packaging
+
+The csproj is configured for a win-x64 self-contained runtime identifier. Use dotnet publish with the desired 
+configuration and runtime identifier to produce distributable artifacts.
+
+## Configuration
+
+Settings exposed in the UI map closely to the CLI options: output folder, filename mask, segment duration and 
+force mode, rotation, crop and detector choices, gravitation bias and detector parameters. Advanced passthrough 
+arguments can still be supplied to FFmpeg via the CLI passthrough field.
+
+## Developer notes
+
+- Project: Splitter-UI (Avalonia 12, net10.0)
+- Key packages: Avalonia, Avalonia.Controls.DataGrid, Avalonia.Desktop, Avalonia.Themes.Fluent, CommunityToolkit.Mvvm
+- The UI project references the splitter-cli project for tight integration during development.
+
+## Troubleshooting
+
+If FFmpeg or FFprobe are not found, the app will be unable to probe media or run splits. Verify tools are on the 
+system PATH and that the runtime matches the built RID.
+
+## Contributing and License
+
+Contributions follow the main repository guidelines. See the root README for contributor and license information.
+
+## Contact
+
+For issues or questions, open an issue on the project repository or contact the 
+maintainer listed in the main README.

Splitter-UI/Services/AutoDecisionService.cs

@@ -0,0 +1,75 @@
+namespace Splitter_UI.Services;
+
+public sealed class AutoDecisionService(IThumbnailService _thumbnails, IFileProbeService _fileProbe, ILogger _log) : IAutoDecisionService
+{
+    public void ApplyAutoDecisions(JobViewModel job, CancellationToken token)
+    {
+        Task.Run(() => Detect(job, token));
+    }
+
+    private async Task Detect(JobViewModel job, CancellationToken token)
+    {
+        try
+        {
+            job.GravitateTo            = new(0.5f, 0.5f);
+            job.OverrideTargetDuration = 58.0;
+            job.Mask                   = "[NAME]_seg[NN].[EXT]";
+            job.OutputFolder           = Path.Combine(Path.GetDirectoryName(job.InputFile)!, "splitter");
+
+            job.Probe           = await _fileProbe.ProbeAsync(job.InputFile, token);
+            job.Thumbnail       = await _thumbnails.CreateThumbnailAsync(job.InputFile, job.Probe, rotateDegree: job.Rotate);
+
+            if (job.Probe.Width > job.Probe.Height)
+            {
+                job.Detect = "body";
+                job.Rotate = 0;
+
+                CalculateCrop(job);
+            }
+            //else
+            //{
+            //    var sampler         = new VideoRotationSampler(null);
+            //    job.Rotate = await sampler.DetectRotationAsync(job.InputFile, job.Probe.Duration, token);
+            //    job.Detect = job.Rotate == 0 ? null : "body";
+            //}
+
+            _log.LogInfo(job.ToString());
+        }
+        catch (Exception ex)
+        {
+            _log.LogError($"Error creating thumbnail for {Path.GetFileName(job.InputFile)}: {ex.Message}");
+        }
+    }
+
+    private static void CalculateCrop(JobViewModel job)
+    {
+        var targetAR = (float)CommandLine.DefaultW / CommandLine.DefaultH;
+        var pixelAspect = job.Probe!.Sar.X / job.Probe.Sar.Y;
+
+        float srcW = job.Probe.Width  * pixelAspect;
+        float srcH = job.Probe.Height;
+        var srcAR = srcW / srcH;
+
+        float cropH = srcH;
+        float cropW = cropH * targetAR;
+
+        if (cropW > srcW)
+        {
+            cropW = srcW;
+            cropH = cropW / targetAR;
+        }
+
+        float x = (srcW - cropW) * 0.5f;
+        float y = (srcH - cropH) * 0.5f;
+
+        float invPixelAspect = 1f / pixelAspect;
+
+        float cropW_px = cropW * invPixelAspect;
+        float cropH_px = cropH;
+
+        float x_px = x * invPixelAspect;
+        float y_px = y;
+
+        job.CropText = $"{(int)MathF.Round(cropW_px)},{(int)MathF.Round(cropH_px)}";
+    }
+}

Splitter-UI/Services/AvaloniaBitmapExtensions.cs

@@ -0,0 +1,42 @@
+using System.Runtime.InteropServices;
+using Avalonia;
+using Avalonia.Media.Imaging;
+
+namespace Splitter_UI.Services;
+
+public static class AvaloniaBitmapExtensions
+{
+    public static Mat ToMatContinuous(this Bitmap bmp)
+    {
+        var w = bmp.PixelSize.Width;
+        var h = bmp.PixelSize.Height;
+        var stride = w * 4;
+        var size = h * stride;
+
+        var buffer = new byte[size];
+        var handle = GCHandle.Alloc(buffer, GCHandleType.Pinned);
+
+        try
+        {
+            bmp.CopyPixels(
+                new PixelRect(0, 0, w, h),
+                handle.AddrOfPinnedObject(),
+                size,
+                stride);
+
+            return Mat.FromPixelData(h, w, MatType.CV_8UC4, buffer);
+        }
+        finally
+        {
+            handle.Free();
+        }
+    }
+
+    public static Mat ToMatBgrContinuous(this Bitmap bmp)
+    {
+        using var bgra = bmp.ToMatContinuous();
+        var bgr = new Mat();
+        Cv2.CvtColor(bgra, bgr, ColorConversionCodes.BGRA2BGR);
+        return bgr;
+    }
+}

Splitter-UI/Services/DummyDetector.cs

@@ -0,0 +1,7 @@
+namespace Splitter_UI.Services;
+
+internal class DummyDetector : IObjectDetector
+{
+    public List<(OpenCvSharp.Rect box, Point2f center)> DetectAll(Mat frameCont) => [];
+    public void Dispose() {}
+}

Splitter-UI/Services/FileJobFactory.cs

@@ -0,0 +1,17 @@
+using Microsoft.Extensions.DependencyInjection;
+
+public sealed class FileJobFactory : IFileJobFactory
+{
+    private readonly IServiceProvider _services;
+
+    public FileJobFactory(IServiceProvider services)
+    {
+        _services = services;
+    }
+
+    public JobViewModel Create(SingleJob job)
+    {
+        // Resolve a fresh VM + fresh services
+        return ActivatorUtilities.CreateInstance<JobViewModel>(_services, job);
+    }
+}

Splitter-UI/Services/FileProbeService.cs

@@ -0,0 +1,10 @@
+namespace Splitter_UI.Services;
+
+public sealed class FileProbeService : IFileProbeService
+{
+    public async Task<VideoInfo> ProbeAsync(string inputFile, CancellationToken token)
+    {
+        var res = await Task.Run(() => ProbeVideo.Probe(inputFile, false, token), token);
+        return res;
+    }
+}

Splitter-UI/Services/GlobalLogger.cs

@@ -0,0 +1,24 @@
+namespace Splitter_UI.Services;
+
+internal class GlobalLogger(ILogService _logService, StatusBarViewModel _statusBar, ProgressViewModel _progress) : ILogger
+{
+    public void ClearProgress(string name, int progressLine) 
+    {
+        if (progressLine == 0)
+            _statusBar.Percent = 0;
+        else
+            _progress.ClearProgress(name, progressLine-1);
+    }
+    public void DrawProgress(string name, int progressLine, double progress, TimeSpan eta, double speed) 
+    {
+        if (progressLine == 0)
+            _statusBar.Percent = progress;
+        else
+            _progress.DrawProgress(name, progressLine - 1, progress, eta, speed);
+    }
+
+    public void Log(string prefix, ConsoleColor color, string msg)
+    {
+        _logService.Log(prefix, color, msg);
+    }
+}

Splitter-UI/Services/IAutoDecisionService.cs

@@ -0,0 +1,6 @@
+namespace Splitter_UI.Services;
+
+public interface IAutoDecisionService
+{
+    void ApplyAutoDecisions(JobViewModel job, CancellationToken token);
+}

Splitter-UI/Services/IFileJobFactory.cs

@@ -0,0 +1,6 @@
+namespace Splitter_UI.Services;
+
+public interface IFileJobFactory
+{
+    JobViewModel Create(SingleJob job);
+}

Splitter-UI/Services/IFileProbeService.cs

@@ -0,0 +1,6 @@
+namespace Splitter_UI.Services;
+
+public interface IFileProbeService
+{
+    Task<VideoInfo> ProbeAsync(string inputFile, CancellationToken token);
+}

Splitter-UI/Services/ILogService.cs

@@ -0,0 +1,7 @@
+
+namespace Splitter_UI.Services;
+
+public interface ILogService
+{
+    void Log(string prefix, ConsoleColor color, string msg);
+}

Splitter-UI/Services/IThumbnailService.cs

@@ -0,0 +1,8 @@
+using Avalonia.Media.Imaging;
+
+namespace Splitter_UI.Services;
+
+public interface IThumbnailService
+{
+    Task<Bitmap?> CreateThumbnailAsync(string file, VideoInfo probe, TimeSpan? skip = null, int? width = null, int? height = null, int? rotateDegree = null);
+}

Splitter-UI/Services/SingleThreadedDetector.cs

@@ -0,0 +1,21 @@
+namespace Splitter_UI.Services;
+
+public class SingleThreadedDetector<T>(IObjectDetector _detector) : IObjectDetector
+    where T : IObjectDetector
+{
+    private Lock _lock = new();
+
+    public List<(OpenCvSharp.Rect box, Point2f center)> DetectAll(Mat frameCont)
+    {
+        lock (_lock)
+        {
+            return _detector.DetectAll(frameCont);
+        }
+    }
+    
+    public void Dispose()
+    {
+        if ( _detector is IDisposable d )
+            d.Dispose();
+    }
+}

Splitter-UI/Services/ThumbnailService.cs

@@ -0,0 +1,167 @@
+using System.Diagnostics;
+using Avalonia;
+using Avalonia.Media.Imaging;
+using Avalonia.Platform;
+
+namespace Splitter_UI.Services;
+
+public sealed class ThumbnailService : IThumbnailService
+{
+    private const int _thumbWidth  = 160;
+    private const int _thumbHeight = 90;
+
+    private readonly byte [] _bgrBuffer  = new byte[_thumbWidth * _thumbHeight * 3];
+    private readonly byte [] _bgraBuffer = new byte[_thumbWidth * _thumbHeight * 4];
+
+    public SemaphoreSlim _lock = new(1,1);
+
+    public async Task<Bitmap?> CreateThumbnailAsync(
+        string file,
+        VideoInfo probe,
+        TimeSpan? skip    = null,
+        int? width        = null,
+        int? height       = null,
+        int? rotateDegree = null)
+    {
+        await _lock.WaitAsync();
+        try
+        {
+            return await CreateThumbnailInternal(
+                file,
+                probe,
+                skip,
+                width,
+                height,
+                rotateDegree
+                );
+        }
+        finally
+        {
+            _lock.Release();
+        }
+    }
+
+    private async Task<Bitmap?> CreateThumbnailInternal(
+        string file,
+        VideoInfo probe,
+        TimeSpan? skip = null,
+        int? width = null,
+        int? height = null,
+        int? rotateDegree = null)
+    {
+        width  ??= _thumbWidth;
+        height ??= _thumbHeight;
+        skip   ??= TimeSpan.Zero;
+
+        // buffer for BGR24 → 3 bytes per pixel
+
+        var canUseStaticBuffers =
+            width.Value == _thumbWidth &&
+            height.Value == _thumbHeight;
+
+        var bgrBuffer  = canUseStaticBuffers ? _bgrBuffer  : new byte[width.Value * height.Value * 3];
+        var bgraBuffer = canUseStaticBuffers ? _bgraBuffer : new byte[width.Value * height.Value * 4];
+
+        // Decode a single frame using ffmpeg → raw BGR24 into _bgrBuffer
+        bool ok = await DecodeFrameAsync(bgrBuffer, file, skip.Value, width.Value, height.Value, rotateDegree);
+        if (!ok)
+            return null;
+
+        // Convert BGR24 → BGRA32
+        ConvertBgrToBgra(bgrBuffer, bgraBuffer, width.Value, height.Value);
+
+        // Create Avalonia Bitmap
+        return CreateBitmap(bgraBuffer, width.Value, height.Value, rotateDegree == 90 || rotateDegree == 270);
+    }
+
+    private static async Task<bool> DecodeFrameAsync(byte [] bgrBuffer, string file, TimeSpan skip, int width, int height, int? rotateDegree)
+    {
+        var rotationStr = TrackingSplitter.GetRorationArg(rotateDegree);
+
+        // ffmpeg command: decode one frame, resize, output raw BGR24
+        var args =
+            $"-ss {skip.TotalSeconds} -t 0.1 -i \"{file}\" " +
+            "-an -sn " +
+            $"-vf \"scale={width}:{height}:force_original_aspect_ratio=decrease," +
+            $"pad={width}:{height}:(ow-iw)/2:(oh-ih)/2,format=bgr24{rotationStr}\" " +
+            "-f rawvideo -";
+
+        var psi = new ProcessStartInfo
+        {
+            FileName               = "ffmpeg",
+            Arguments              = args,
+            RedirectStandardOutput = true,
+            RedirectStandardError  = true,
+            UseShellExecute        = false,
+            CreateNoWindow         = true
+        };
+
+        var p = new Process { StartInfo = psi };
+        p.Start();
+
+        int needed = bgrBuffer.Length;
+        int read = 0;
+
+        using var stdout = p.StandardOutput.BaseStream;
+
+        while (read < needed)
+        {
+            int r = await stdout.ReadAsync(bgrBuffer, read, needed - read);
+            if (r == 0)
+            {
+                TryKill(p);
+                return false;
+            }
+            read += r;
+        }
+
+        TryKill(p);
+        return true;
+    }
+
+    private static void TryKill(Process p)
+    {
+        try { p.Kill(); } catch { }
+    }
+
+    private static void ConvertBgrToBgra(byte[] bgr, byte[] bgra, int width, int height)
+    {
+        int si = 0;
+        int di = 0;
+
+        int totalPixels = width * height;
+
+        for (int i = 0; i < totalPixels; i++)
+        {
+            bgra[di + 0] = bgr[si + 0]; // B
+            bgra[di + 1] = bgr[si + 1]; // G
+            bgra[di + 2] = bgr[si + 2]; // R
+            bgra[di + 3] = 255;         // A
+
+            si += 3;
+            di += 4;
+        }
+    }
+
+    private static unsafe Bitmap CreateBitmap(byte[] bgra, int width, int height, bool isRotated)
+    {
+        if (isRotated)
+        {
+            (height, width) = (width, height);
+        }
+
+        int stride = width * 4;
+
+        fixed (byte* p = bgra)
+        {
+            return new Bitmap(
+                PixelFormat.Bgra8888,
+                AlphaFormat.Premul,
+                (nint)p,
+                new PixelSize(width, height),
+                new Vector(96, 96),
+                stride);
+        }
+    }
+
+}

Splitter-UI/Splitter-UI.csproj

@@ -0,0 +1,37 @@
+<Project Sdk="Microsoft.NET.Sdk">
+  <PropertyGroup>
+    <OutputType>WinExe</OutputType>
+    <TargetFramework>net10.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+    <LangVersion>latest</LangVersion>
+    <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
+    <PlatformTarget>x64</PlatformTarget>
+    <RuntimeIdentifier>win-x64</RuntimeIdentifier>
+    <ApplicationManifest>app.manifest</ApplicationManifest>
+    <AvaloniaUseCompiledBindingsByDefault>true</AvaloniaUseCompiledBindingsByDefault>
+    <ApplicationIcon>Assets/splitter.ico</ApplicationIcon>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <AvaloniaResource Include="Assets\**" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Avalonia" Version="12.0.3" />
+    <PackageReference Include="Avalonia.Controls.DataGrid" Version="12.0.0" />
+    <PackageReference Include="Avalonia.Desktop" Version="12.0.3" />
+    <PackageReference Include="Avalonia.Themes.Fluent" Version="12.0.3" />
+    <PackageReference Include="Avalonia.Fonts.Inter" Version="12.0.3" />
+    <PackageReference Include="AvaloniaUI.DiagnosticsSupport" Version="2.2.1">
+      <IncludeAssets Condition="'$(Configuration)' != 'Debug'">None</IncludeAssets>
+      <PrivateAssets Condition="'$(Configuration)' != 'Debug'">All</PrivateAssets>
+    </PackageReference>
+    <PackageReference Include="CommunityToolkit.Mvvm" Version="8.4.2" />
+    <PackageReference Include="Microsoft.Extensions.DependencyInjection" Version="10.0.8" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\splitter-cli\splitter.csproj" />
+  </ItemGroup>
+</Project>

Splitter-UI/ViewLocator.cs

@@ -0,0 +1,34 @@
+using System.Diagnostics.CodeAnalysis;
+using Avalonia.Controls;
+using Avalonia.Controls.Templates;
+
+namespace Splitter_UI;
+/// <summary>
+/// Given a view model, returns the corresponding view if possible.
+/// </summary>
+[RequiresUnreferencedCode(
+    "Default implementation of ViewLocator involves reflection which may be trimmed away.",
+    Url = "https://docs.avaloniaui.net/docs/concepts/view-locator")]
+public class ViewLocator : IDataTemplate
+{
+    public Control? Build(object? param)
+    {
+        if (param is null)
+            return null;
+
+        var name = param.GetType().FullName!.Replace("ViewModel", "View", StringComparison.Ordinal);
+        var type = Type.GetType(name);
+
+        if (type != null)
+        {
+            return (Control)Activator.CreateInstance(type)!;
+        }
+
+        return new TextBlock { Text = "Not Found: " + name };
+    }
+
+    public bool Match(object? data)
+    {
+        return data is ViewModelBase;
+    }
+}

Splitter-UI/ViewModels/FileListViewModel.cs

@@ -0,0 +1,59 @@
+using System.Collections.ObjectModel;
+using CommunityToolkit.Mvvm.ComponentModel;
+using CommunityToolkit.Mvvm.Input;
+
+namespace Splitter_UI.ViewModels;
+
+public partial class FileListViewModel : ObservableObject
+{
+    private readonly IFileJobFactory _factory;
+    private readonly IAutoDecisionService _autoDecisionService;
+    public ObservableCollection<JobViewModel> Files { get; } = [];
+    public ObservableCollection<JobViewModel> SelectedFiles { get; } = [];
+
+    [ObservableProperty]
+    private JobViewModel? _selected;
+
+    public event Action<JobViewModel?>? SelectedFileChanged;
+
+    public FileListViewModel(IFileJobFactory factory, IAutoDecisionService autoDecisionService)
+    {
+        _factory = factory;
+        _autoDecisionService = autoDecisionService;
+    }
+
+    partial void OnSelectedChanged(JobViewModel? value)
+        => SelectedFileChanged?.Invoke(value);
+
+    [RelayCommand]
+    private void AddFiles(IEnumerable<string> paths)
+    {
+        foreach (var path in paths)
+        {
+            // Probe + auto-detect + thumbnail
+            var job = new SingleJob { InputFile = path };
+            var vm = _factory.Create(job);
+            Files.Add(vm);
+            _autoDecisionService.ApplyAutoDecisions(vm, CancellationToken.None);
+        }
+
+        Selected = Files.LastOrDefault();
+    }
+
+    internal void DeleteSelected()
+    {
+        if (SelectedFiles.Any()) 
+        {
+            var toDelete = SelectedFiles.ToList();
+            foreach (var item in toDelete)
+                Files.Remove(item);
+        }
+        else if ( Selected != null)
+        {
+            var sel = Selected;
+            Files.Remove(sel);
+        }
+
+        Selected = Files.LastOrDefault();
+    }
+}

Splitter-UI/ViewModels/InspectorPaneViewModel.cs

@@ -0,0 +1,75 @@
+using System.Collections.ObjectModel;
+using CommunityToolkit.Mvvm.ComponentModel;
+using CommunityToolkit.Mvvm.Input;
+
+namespace Splitter_UI.ViewModels;
+
+public partial class InspectorPaneViewModel : ObservableObject
+{
+    [ObservableProperty]
+    private JobViewModel? _selected;
+
+    public ObservableCollection<JobViewModel> Files { get; set; } = [];
+
+    public List<string> DetectModes => 
+        [  
+            "face", "body", "none"
+        ];
+
+    [RelayCommand]
+    private void TransformAll()
+    {
+        _ = _main.Start();
+    }
+
+
+    [RelayCommand]
+    private void ApplyOverrides()
+    {
+        if (Selected is null)
+            return;
+
+        foreach (JobViewModel job in Files.Where(x => !ReferenceEquals(x, Selected)))
+        {
+            job.Detect                 = Selected.Detect;
+            job.Rotate                 = Selected.Rotate;
+            job.CropText               = Selected.CropText;
+            job.ForceFixed             = Selected.ForceFixed;
+            job.GravitateText          = Selected.GravitateText;
+            job.Mask                   = Selected.Mask;
+            job.OutputFolder           = Selected.OutputFolder;
+            job.OverrideTargetDuration = Selected.OverrideTargetDuration;
+            job.PassthroughText        = Selected.PassthroughText;
+            
+            job.ParametersList.Clear();
+            foreach (var param in Selected.ParametersList)
+                job.ParametersList.Add(param);
+        }
+    }
+
+    public IRelayCommand RotateLeftCommand { get; }
+    public IRelayCommand RotateRightCommand { get; }
+
+    private MainViewModel _main = null!;
+
+    public InspectorPaneViewModel()
+    {
+        RotateLeftCommand = new RelayCommand(() => AdjustRotation(-90));
+        RotateRightCommand = new RelayCommand(() => AdjustRotation(+90));
+    }
+
+    public void SetMain(MainViewModel main) => _main = main;
+
+    private void AdjustRotation(int delta)
+    {
+        if ( Selected == null)
+            return;
+
+        var r = Selected.Rotate;
+        r = (r + delta) % 360;
+        if (r < 0) r += 360;
+
+        Selected.Rotate = r;
+    }
+
+}

Splitter-UI/ViewModels/JobViewModel.cs

@@ -0,0 +1,372 @@
+using System.Collections.ObjectModel;
+using System.Collections.Specialized;
+using System.ComponentModel;
+using Avalonia.Media.Imaging;
+using Avalonia.Threading;
+using CommunityToolkit.Mvvm.ComponentModel;
+using CommunityToolkit.Mvvm.Input;
+
+namespace Splitter_UI.ViewModels;
+
+public partial class JobViewModel : ObservableObject
+{
+    private SingleJob Job { get; }
+
+    public SingleJob GetJob() => Job;
+
+    [ObservableProperty] private VideoInfo?    _probe;
+    [ObservableProperty] private PreviewData?  _preview = new(null, [], null, new(0.5f, 0.5f));
+    [ObservableProperty] private Bitmap?       _thumbnail;
+    [ObservableProperty] private double        _sliderLiveValue;
+    [ObservableProperty] private double        _positionSeconds;
+
+    public string InputFile       => Job.InputFile;
+    public double DurationSeconds => Probe?.Duration ?? 0;
+
+    public IRelayCommand StepForwardCommand  { get; }
+    public IRelayCommand StepBackwardCommand { get; }
+
+    private readonly IThumbnailService             _thumbnails;
+    private readonly DispatcherTimer               _debounceTimer;
+    private readonly Func<string, IObjectDetector> _detectorFactory;
+    private readonly ILogger                       _log;
+
+    public string FileName => Path.GetFileName(Job.InputFile);
+
+    public string TextDesc => Probe != null 
+        ? $"{Probe.Width}x{Probe.Height}, {TimeSpan.FromSeconds(Probe.Duration).ToString(@"hh\:mm\:ss")}), FPS: {Probe.Fps:F2}, Bitrate: {Probe.Bitrate/1024/1024:F2} MB/s"
+        : "";
+
+    public override string ToString() => $"{FileName}: {TextDesc}";
+
+    public ObservableCollection<ParameterEntry> ParametersList { get; }
+        = new();
+
+    public string CropText
+    {
+        get => Job.Crop is { } c ? $"{c.width},{c.height}" : "";
+        set
+        {
+            if (string.IsNullOrWhiteSpace(value))
+            {
+                Job.Crop = null;
+            }
+            else
+            {
+                var parts = value.Split(',');
+                if (parts.Length == 2 &&
+                    int.TryParse(parts[0], out var w) &&
+                    int.TryParse(parts[1], out var h))
+                    Job.Crop = (w, h);
+            }
+            OnPropertyChanged();
+        }
+    }
+
+    public string GravitateText
+    {
+        get => Job.GravitateTo is { } p ? $"{p.X:F3},{p.Y:F3}" : "";
+        set
+        {
+            if (string.IsNullOrWhiteSpace(value))
+            {
+                Job.GravitateTo = null;
+            }
+            else
+            {
+                var parts = value.Split(',');
+                if (parts.Length == 2 &&
+                    float.TryParse(parts[0], out var x) &&
+                    float.TryParse(parts[1], out var y))
+                    Job.GravitateTo = new Point2f(x, y);
+            }
+            OnPropertyChanged();
+            OnPropertyChanged(nameof(GravitateTo));
+        }
+    }
+
+    public string PassthroughText
+    {
+        get => string.Join(' ', Job.Passthrough);
+        set
+        {
+            Job.Passthrough = string.IsNullOrWhiteSpace(value)
+                ? Array.Empty<string>()
+                : value.Split(' ', StringSplitOptions.RemoveEmptyEntries);
+            OnPropertyChanged();
+        }
+    }
+
+    public string? Detect
+    {
+        get => Job.Detect;
+        set
+        {
+            if (Job.Detect == value)
+                return;
+            Job.Detect = value;
+            OnPropertyChanged();
+        }
+    }
+
+    public string? Mask
+    {
+        get => Job.Mask;
+        set
+        {
+            if (Job.Mask == value)
+                return;
+            Job.Mask = value;
+            OnPropertyChanged();
+        }
+    }
+
+    public string OutputFolder
+    {
+        get => Job.OutputFolder;
+        set
+        {
+            if (Job.OutputFolder == value)
+                return;
+            Job.OutputFolder = value;
+            OnPropertyChanged();
+        }
+    }
+
+    public bool ForceFixed
+    {
+        get => Job.ForceFixed;
+        set
+        {
+            if (Job.ForceFixed == value)
+                return;
+            Job.ForceFixed = value;
+            OnPropertyChanged();
+        }
+    }
+
+    public bool Debug
+    {
+        get => Job.Debug;
+        set
+        {
+            if (Job.Debug == value)
+                return;
+            Job.Debug = value;
+            OnPropertyChanged();
+        }
+    }
+
+    public int? Rotate
+    {
+        get => Job.Rotate;
+        set
+        {
+            Job.Rotate = value;
+            OnPropertyChanged();
+            Task.Run(CreatePreview);
+        }
+    }
+
+    public Point2f GravitateTo
+    {
+        get => Job.GravitateTo ?? new Point2f(0.5f, 0.5f);
+        set
+        {
+            if (Job.GravitateTo != null && Math.Abs(Job.GravitateTo.Value.X - value.X) < 0.001 && Math.Abs(Job.GravitateTo.Value.Y - value.Y) < 0.001)
+                return;
+
+            Job.GravitateTo = value;
+            OnPropertyChanged();
+            OnPropertyChanged(nameof(GravitateText));
+        }
+    }
+
+    public double? OverrideTargetDuration
+    {
+        get => Job.OverrideTargetDuration;
+        set
+        {
+            if (Job.OverrideTargetDuration != null && value != null && Math.Abs(Job.OverrideTargetDuration.Value - value.Value) < 0.01)
+                return;
+            Job.OverrideTargetDuration = value;
+            OnPropertyChanged();
+        }
+    }
+    public JobViewModel(SingleJob job, IThumbnailService thumbnails, Func<string, IObjectDetector> detectorFactory, ILogger log)
+    {
+        Job              = job;
+        _thumbnails      = thumbnails;
+        _detectorFactory = detectorFactory;
+        _log             = log;
+
+        ParametersList.Add(new ParameterEntry("DropoutToleranceFrames"      , ""));
+        ParametersList.Add(new ParameterEntry("EmaFactor"                   , ""));
+        ParametersList.Add(new ParameterEntry("CameraEasing"                , ""));
+        ParametersList.Add(new ParameterEntry("LostFreezeFrames"            , ""));
+        ParametersList.Add(new ParameterEntry("RotationDetectorSampleCount" , ""));
+        ParametersList.Add(new ParameterEntry("RotationDetectorSampleLength", ""));
+        ParametersList.Add(new ParameterEntry("RotationDetectorFrameWidth"  , ""));
+        ParametersList.Add(new ParameterEntry("RotationDetectorFrameHeight" , ""));
+
+        foreach (var entry in ParametersList)
+        {
+            entry.PropertyChanged += OnParameterChanged;
+        }
+
+        PropertyChanged += (sender, e) =>
+        {
+            if (e.PropertyName == nameof(Probe))
+            {
+                OnPropertyChanged(nameof(DurationSeconds));
+            }
+        };
+        ParametersList.CollectionChanged += OnParametersCollectionChanged;
+
+        StepForwardCommand  = new RelayCommand(StepForward);
+        StepBackwardCommand = new RelayCommand(StepBackward);
+
+        _debounceTimer = new DispatcherTimer
+        {
+            Interval = TimeSpan.FromSeconds(1)
+        };
+        _debounceTimer.Tick += DebounceTimerTick;
+    }
+
+    public async Task CreatePreview()
+    {
+        if ( Probe == null)
+            return;
+        try
+        {
+            var frame    = await _thumbnails.CreateThumbnailAsync(Job.InputFile, Probe, TimeSpan.FromSeconds(PositionSeconds), Probe.Width, Probe.Height, Job.Rotate);
+            if (  frame == null )
+                return;
+
+            Preview      = new PreviewData(frame, [], null, Job.GravitateTo ?? new (0.5f, 0.5f));
+
+            var detector = _detectorFactory(Job.Detect ?? "");
+            var detections = detector.DetectAll(frame.ToMatContinuous());
+
+            Rect? crop = null;
+            if (detections.Count > 0)
+            {
+                var primaryDetection = detections
+                    .OrderByDescending(d => d.box.Height * d.box.Width)
+                    .FirstOrDefault();
+
+                var w = Probe.Width;
+                var h = Probe.Height;
+
+                var cropWidth  = Job.Crop?.width  ?? CommandLine.DefaultW;
+                var cropHeight = Job.Crop?.height ?? CommandLine.DefaultH;
+
+                var cx = primaryDetection.center.X - cropWidth  / 2f;
+                var cy = primaryDetection.center.Y - cropHeight / 2f;
+
+                var r = new Rect(cx, cy, cropWidth, cropHeight);
+
+                crop = ClampCrop(r, w, h);
+            }
+
+            var boxes = detections.Select(x => x.box).ToList();
+            Preview = new PreviewData(frame, boxes, crop, Job.GravitateTo ?? new (0.5f, 0.5f));
+        }
+        catch (Exception ex)
+        {
+            _log.LogError($"Error creating preview for {FileName}: {ex.Message}");
+        }
+    }
+
+    private static Rect ClampCrop(Rect r, float w, float h)
+    {
+        var x = r.X;
+        var y = r.Y;
+        var cw = r.Width;
+        var ch = r.Height;
+
+        if (x < 0) x = 0;
+        if (y < 0) y = 0;
+
+        if (x + cw > w) x = w - cw;
+        if (y + ch > h) y = h - ch;
+
+        if (x < 0) x = 0;
+        if (y < 0) y = 0;
+
+        return new Rect(x, y, cw, ch);
+    }
+
+
+    private void OnParameterChanged(object? sender, PropertyChangedEventArgs e)
+    {
+        if (sender is ParameterEntry p && e.PropertyName == nameof(ParameterEntry.Value))
+        {
+            Job.Parameters[p.Key] = p.Value;
+        }
+    }
+
+    private void OnParametersCollectionChanged(object? sender, NotifyCollectionChangedEventArgs e)
+    {
+        if (e.NewItems != null)
+        {
+            foreach (ParameterEntry p in e.NewItems)
+            {
+                Job.Parameters[p.Key] = p.Value;
+                p.PropertyChanged += OnParameterChanged;
+            }
+        }
+
+        if (e.OldItems != null)
+        {
+            foreach (ParameterEntry p in e.OldItems)
+            {
+                Job.Parameters.Remove(p.Key);
+                p.PropertyChanged -= OnParameterChanged;
+            }
+        }
+    }
+
+    private void StepForward()
+    {
+        if (DurationSeconds <= 0)
+            return;
+
+        var step = DurationSeconds * 0.1; // 10% of total duration
+
+        SliderLiveValue = Math.Min(DurationSeconds, SliderLiveValue + step);
+        // trigger seek in your playback pipeline here
+    }
+
+    private void StepBackward()
+    {
+        if (DurationSeconds <= 0)
+            return;
+
+        var step = DurationSeconds * 0.1; // 10% of total duration
+
+        SliderLiveValue = Math.Max(0, SliderLiveValue - step);
+        // trigger seek in your playback pipeline here
+    }
+
+    partial void OnSliderLiveValueChanged(double value)
+    {
+        // Restart debounce timer on every slider update
+        _debounceTimer.Stop();
+        _debounceTimer.Start();
+    }
+
+    private void DebounceTimerTick(object? sender, EventArgs e)
+    {
+        _debounceTimer.Stop();
+
+        // Commit the final value
+        PositionSeconds = SliderLiveValue;
+    }
+
+    partial void OnPositionSecondsChanged(double value)
+    {
+        Task.Run(CreatePreview);
+    }
+
+}

Splitter-UI/ViewModels/LogPaneViewModel.cs

@@ -0,0 +1,36 @@
+using Avalonia.Threading;
+using CommunityToolkit.Mvvm.ComponentModel;
+using System.Collections.ObjectModel;
+
+namespace Splitter_UI.ViewModels;
+
+public sealed record LogEntry(string Prefix, ConsoleColor Color, string Message);
+
+public partial class LogPaneViewModel : ObservableObject, ILogService
+{
+    public ObservableCollection<LogEntry> Logs { get; } = [];
+
+    public void Log(string prefix, ConsoleColor color, string msg)
+    {
+        Add(new LogEntry(prefix.Replace("[", "").Replace("]", ""), color, msg));
+    }
+
+    private void Add(LogEntry entry)
+    {
+        if (Dispatcher.UIThread.CheckAccess())
+        {
+            AddInternal(entry);
+        }
+        else
+        {
+            Dispatcher.UIThread.Post(() => AddInternal(entry));
+        }
+    }
+
+    private void AddInternal(LogEntry entry)
+    {
+        Logs.Add(entry);
+        if (Logs.Count > 5000)
+            Logs.RemoveAt(0);
+    }
+}

Splitter-UI/ViewModels/MainViewModel.cs

@@ -0,0 +1,94 @@
+using CommunityToolkit.Mvvm.ComponentModel;
+
+namespace Splitter_UI.ViewModels;
+
+public partial class MainViewModel : ViewModelBase
+{
+    public FileListViewModel FileList       { get; }
+    public PreviewPaneViewModel Preview     { get; }
+    public InspectorPaneViewModel Inspector { get; }
+    public StatusBarViewModel StatusBar     { get; }
+    public LogPaneViewModel LogPane         { get; }
+    public ProgressViewModel Progress       { get; }
+    private IJobProcessor _processor = null!;
+
+    [ObservableProperty] private bool _transformMode = false;
+    private ILogger _logger;
+
+    private CancellationTokenSource? _cancellationTokenSource;
+
+    public MainViewModel(
+        FileListViewModel fileListVM,
+        PreviewPaneViewModel ppVM,
+        InspectorPaneViewModel iVM,
+        LogPaneViewModel lpVM,
+        StatusBarViewModel sbVM,
+        ProgressViewModel pVM,
+        IJobProcessor processor,
+        ILogger logger
+        )
+    {
+        FileList   = fileListVM;
+        Preview    = ppVM;
+        Inspector  = iVM;
+        LogPane    = lpVM;
+        StatusBar  = sbVM;
+        Progress   = pVM;
+        _processor = processor;
+        _logger = logger;
+
+        // Wire selection -> preview + inspector
+        FileList.SelectedFileChanged += file =>
+        {
+            Preview.Selected = file;
+            Inspector.Selected = file;
+        };
+
+        Progress.SetMain(this);
+        Inspector.SetMain(this);
+        Inspector.Files = FileList.Files;
+    }
+
+    public void Cancel()
+    {
+        _cancellationTokenSource?.Cancel();
+    }
+
+    public async Task Start()
+    {
+        _cancellationTokenSource = new CancellationTokenSource();
+        try
+        {
+            StatusBar.StatusText = "Processing…";
+            StatusBar.Percent    = 0;
+            TransformMode        = true;
+
+            var files = FileList.Files.ToList();
+            var jobs = new List<SingleTask>();
+
+            foreach (var file in files)
+            {
+                var fileJobs = await _processor.GenerateJobs(file.GetJob(), false, _cancellationTokenSource.Token);
+                jobs.AddRange(fileJobs);
+            }
+
+            await _processor.ProcessJobs(jobs, false, _cancellationTokenSource.Token);
+        }
+        catch (Exception ex)
+        {
+            // Handle exception
+            StatusBar.StatusText = "Error occurred…";
+            _logger.LogError($"Error: {ex.Message}");
+            _cancellationTokenSource.Cancel();
+        }
+        finally
+        {
+            StatusBar.StatusText = "Ready…";
+            StatusBar.Percent    = 0;
+            TransformMode        = false;
+
+            _cancellationTokenSource?.Dispose();
+        }
+    }
+
+}

Splitter-UI/ViewModels/PreviewPaneViewModel.cs

@@ -0,0 +1,51 @@
+using System.ComponentModel;
+using CommunityToolkit.Mvvm.ComponentModel;
+
+namespace Splitter_UI.ViewModels;
+
+public partial class PreviewPaneViewModel : ObservableObject
+{
+    [ObservableProperty]
+    private JobViewModel? _selected;
+
+    public PreviewData? Preview => Selected?.Preview;
+    public Point2f? Sar         => Selected?.Probe?.Sar;
+    public int Rotate           => Selected?.Rotate ?? 0;
+    public Point2f GravitateTo
+    {
+        get => Selected?.GravitateTo ?? new Point2f(0.5f, 0.5f);
+        set
+        {
+            if (Selected == null)
+                return;
+            Selected.GravitateTo = value;
+            OnPropertyChanged(nameof(GravitateTo));
+        }
+    }
+
+    partial void OnSelectedChanged(JobViewModel? oldValue, JobViewModel? newValue)
+    {
+        if (oldValue != null)
+            oldValue.PropertyChanged -= SelectedPropertyChanged;
+
+        if (newValue != null)
+            newValue.PropertyChanged += SelectedPropertyChanged;
+
+        OnPropertyChanged(nameof(Preview));
+        OnPropertyChanged(nameof(Sar));
+        OnPropertyChanged(nameof(Rotate));
+    }
+
+    private void SelectedPropertyChanged(object? sender, PropertyChangedEventArgs e)
+    {
+        if (e.PropertyName == nameof(JobViewModel.Preview))
+            OnPropertyChanged(nameof(Preview));
+
+        if (e.PropertyName == nameof(JobViewModel.Probe))
+        {
+            OnPropertyChanged(nameof(Sar));
+            OnPropertyChanged(nameof(Rotate));
+        }
+    }
+}
+

Splitter-UI/ViewModels/ProgressViewModel.cs

@@ -0,0 +1,59 @@
+using System.Collections.ObjectModel;
+using CommunityToolkit.Mvvm.ComponentModel;
+using CommunityToolkit.Mvvm.Input;
+using Splitter_UI.Views;
+
+namespace Splitter_UI.ViewModels;
+
+public record ProgressInfo(string Name, int ProgressLine, double Progress, TimeSpan Eta, double Speed);
+
+public partial class ProgressViewModel : ObservableObject
+{
+    [ObservableProperty] private int _numberOfProcesses = 0;
+    public ObservableCollection<ProgressInfo> Processes { get; } = [];
+
+    private Lock _lock = new();
+
+    private MainViewModel _mainModel = null!;
+
+    [RelayCommand]
+    private void Cancel()
+    {
+        _mainModel.Cancel();
+    }
+
+    public void SetMain(MainViewModel mainModel)
+    {
+        _mainModel = mainModel;
+    }
+
+    public void ClearProgress(string name, int progressLine)
+    {
+        lock (_lock)
+        {
+            if (progressLine < 0 || progressLine > Processes.Count)
+                return;
+
+            NumberOfProcesses -= 1;
+            Processes[progressLine] = new ProgressInfo("", progressLine, 0, TimeSpan.Zero, 0);
+        }
+    }
+    public void DrawProgress(string name, int progressLine, double progress, TimeSpan eta, double speed)
+    {
+        lock (_lock)
+        {
+            if (progressLine < 0)
+                return;
+
+            while (Processes.Count <= progressLine)
+            {
+                Processes.Add(new ProgressInfo("", Processes.Count, 0, TimeSpan.Zero, 0));
+            }
+
+            if (Processes[progressLine].Name == "")
+                NumberOfProcesses += 1;
+            Processes[progressLine] = new ProgressInfo(name, progressLine, progress, eta, speed);
+        }
+    }
+}
+

Splitter-UI/ViewModels/StatusBarViewModel.cs

@@ -0,0 +1,13 @@
+using CommunityToolkit.Mvvm.ComponentModel;
+
+namespace Splitter_UI.ViewModels;
+
+public partial class StatusBarViewModel : ObservableObject
+{
+    [ObservableProperty]
+    private string _statusText = "Ready";
+
+    [ObservableProperty]
+    private double _percent;
+
+}

Splitter-UI/ViewModels/ViewModelBase.cs

@@ -0,0 +1,7 @@
+using CommunityToolkit.Mvvm.ComponentModel;
+
+namespace Splitter_UI.ViewModels;
+
+public abstract class ViewModelBase : ObservableObject
+{
+}

Splitter-UI/Views/FileListView.axaml

@@ -0,0 +1,80 @@
+<UserControl
+    xmlns="https://github.com/avaloniaui"
+    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+    xmlns:vm="clr-namespace:Splitter_UI.ViewModels"
+    xmlns:views="clr-namespace:Splitter_UI.Views"
+    xmlns:conv="clr-namespace:Splitter_UI.Converters"
+    x:Class="Splitter_UI.Views.FileListView"
+    x:DataType="vm:FileListViewModel"
+    KeyDown="OnKeyDown"
+    Focusable="True">
+
+    <UserControl.Resources>
+        <conv:ZeroToBoolConverter x:Key="ZeroToBoolConverter"/>
+        <conv:RotationAngleToIconConverter x:Key="RotationAngleToIconConverter"/>
+    </UserControl.Resources>
+
+    <UserControl.Styles>
+        <Style Selector="views|FileListView Border#DropZone">
+            <Setter Property="BorderBrush" Value="Transparent"/>
+            <Setter Property="BorderThickness" Value="0"/>
+        </Style>
+        <Style Selector="views|FileListView[IsDragActive=true] Border#DropZone">
+            <Setter Property="BorderBrush" Value="Red"/>
+            <Setter Property="BorderThickness" Value="2"/>
+        </Style>
+
+    </UserControl.Styles>
+
+    <Border x:Name="DropZone"
+            Background="#1E1E1E"
+            Padding="10"
+            DragDrop.AllowDrop="True"
+            DragDrop.Drop="OnDrop"
+            DragDrop.DragOver="OnDragOver"
+            DragDrop.DragEnter="OnDragEnter"
+            DragDrop.DragLeave="OnDragLeave">
+
+
+        <Grid>
+
+            <!-- Empty message -->
+            <TextBlock Text="Drag files here"
+                       HorizontalAlignment="Center"
+                       VerticalAlignment="Center"
+                       FontSize="20"
+                       Foreground="#666"
+                       IsVisible="{Binding Files.Count, Converter={StaticResource ZeroToBoolConverter}}"/>
+
+            <!-- File list -->
+            <ScrollViewer>
+                <ListBox ItemsSource="{Binding Files}"
+                         SelectedItems="{Binding SelectedFiles}"
+                         SelectedItem="{Binding Selected}"
+                         SelectionMode="Multiple"
+                         BorderThickness="0"
+                         Background="Transparent">
+
+                    <ListBox.ItemsPanel>
+                        <ItemsPanelTemplate>
+                            <WrapPanel Orientation="Horizontal"/>
+                        </ItemsPanelTemplate>
+                    </ListBox.ItemsPanel>
+
+                    <ListBox.Styles>
+                        <Style Selector="ListBoxItem:selected /template/ ContentPresenter">
+                            <Setter Property="Background" Value="#9A9A9A"/>
+                    </Style>
+                    </ListBox.Styles>
+
+                    <ListBox.ItemTemplate>
+                        <DataTemplate x:DataType="vm:JobViewModel">
+                            <views:JobListItemView/>
+                        </DataTemplate>
+                    </ListBox.ItemTemplate>
+
+                </ListBox>
+            </ScrollViewer>
+        </Grid>
+    </Border>
+</UserControl>

Splitter-UI/Views/FileListView.axaml.cs

@@ -0,0 +1,78 @@
+using Avalonia;
+using Avalonia.Controls;
+using Avalonia.Input;
+using Avalonia.Platform.Storage;
+
+namespace Splitter_UI.Views;
+
+public partial class FileListView : UserControl
+{
+    public static readonly StyledProperty<bool> IsDragActiveProperty =
+        AvaloniaProperty.Register<FileListView, bool>(nameof(IsDragActive));
+
+    public bool IsDragActive
+    {
+        get => GetValue(IsDragActiveProperty);
+        set => SetValue(IsDragActiveProperty, value);
+    }
+
+    public FileListView()
+    {
+        InitializeComponent();
+    }
+
+    private void OnKeyDown(object? sender, KeyEventArgs e)
+    {
+        if (e.Key == Key.Delete)
+        {
+            if (DataContext is FileListViewModel vm)
+                vm.DeleteSelected();
+        }
+    }
+    private void OnDragEnter(object? sender, DragEventArgs e)
+    {
+        IsDragActive = true;
+    }
+
+    private void OnDragLeave(object? sender, DragEventArgs e)
+    {
+        IsDragActive = false;
+    }
+
+    private void OnDragOver(object? sender, DragEventArgs e)
+    {
+        // Avalonia 12:
+        // e.Data is IDataObject, but it has NO strongly typed formats.
+        if (e.DataTransfer.Contains(DataFormat.File))
+            e.DragEffects = DragDropEffects.Copy;
+        else
+            e.DragEffects = DragDropEffects.None;
+
+        e.Handled = true;
+    }
+
+    private async void OnDrop(object? sender, DragEventArgs e)
+    {
+        IsDragActive = false;
+
+        if (DataContext is not FileListViewModel vm)
+            return;
+
+        if (!e.DataTransfer.Contains(DataFormat.File))
+            return;
+
+        // Avalonia 12:
+        // This is the ONLY correct way to get dropped files.
+        var items = e.DataTransfer.TryGetFiles();
+        if (items is null)
+            return;
+
+        var paths = items
+            .OfType<IStorageFile>()
+            .Select(f => f.Path.LocalPath)
+            .ToList();
+
+        if (paths.Count > 0)
+            vm.AddFilesCommand.Execute(paths);
+    }
+}

Splitter-UI/Views/InspectorPane.axaml

@@ -0,0 +1,169 @@
+<UserControl
+xmlns="https://github.com/avaloniaui"
+xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+x:Class="Splitter_UI.Views.InspectorPane"
+xmlns:vm="clr-namespace:Splitter_UI.ViewModels"
+x:DataType="vm:InspectorPaneViewModel">
+
+    <Border Background="#252525" Padding="12">
+        <ScrollViewer>
+            <StackPanel Spacing="2">
+
+                <TextBlock Text="Parameters" FontSize="10" Margin="0,0,0,10" FontWeight="Bold"/>
+
+                <!-- InputFile -->
+                <StackPanel Orientation="Vertical" Spacing="8">
+                    <TextBlock Text="{Binding Selected.FileName}" Width="360" Margin="0,0,0,5" FontStyle="Italic"/>
+                    <TextBlock Text="{Binding Selected.TextDesc}" Width="360" FontSize="10" Margin="0,0,0,10" FontWeight="Bold" Foreground="#676767"/>
+                </StackPanel>
+
+                <!-- Rotate -->
+                <StackPanel Orientation="Horizontal" Spacing="8">
+                    <TextBlock Text="Rotate" Width="120"/>
+
+                    <StackPanel Orientation="Horizontal" Spacing="4">
+
+                        <Button Width="24" Height="24"
+                                Padding="0"
+                                Command="{Binding RotateLeftCommand}">
+                            <TextBlock FontFamily="{StaticResource FontAwesome}"
+                                       Text="&#xf2ea;"
+                                       FontSize="12"
+                                       VerticalAlignment="Center"
+                                       HorizontalAlignment="Center"
+                                       Margin="0,-1,0,0"/>
+                        </Button>
+
+                        <Button Width="24" Height="24"
+                                Padding="0"
+                                Command="{Binding RotateRightCommand}">
+                            <TextBlock FontFamily="{StaticResource FontAwesome}"
+                                       Text="&#xf2f9;"
+                                       FontSize="12"
+                                       VerticalAlignment="Center"
+                                       HorizontalAlignment="Center"
+                                       Margin="0,-1,0,0"/>
+                        </Button>
+
+
+                        <!-- Angle display -->
+                        <TextBlock Text="{Binding Selected.Rotate}"
+                                    Width="40"
+                                    HorizontalAlignment="Center"
+                                    VerticalAlignment="Center"/>
+                    </StackPanel>
+                </StackPanel>
+
+                <!-- Mask -->
+                <StackPanel Orientation="Horizontal" Spacing="8">
+                    <TextBlock Text="Mask" Width="120"/>
+                    <TextBox Text="{Binding Selected.Mask}" Width="260"/>
+                </StackPanel>
+
+                <!-- OutputFolder -->
+                <StackPanel Orientation="Horizontal" Spacing="8">
+                    <TextBlock Text="Output Folder" Width="120"/>
+                    <TextBox Text="{Binding Selected.OutputFolder}" Width="260"/>
+                </StackPanel>
+
+                <!-- Crop -->
+                <StackPanel Orientation="Horizontal" Spacing="8">
+                    <TextBlock Text="Crop (w,h)" Width="120"/>
+                    <TextBox Text="{Binding Selected.CropText}" Width="160"/>
+                </StackPanel>
+
+                <!-- GravitateTo -->
+                <StackPanel Orientation="Horizontal" Spacing="8">
+                    <TextBlock Text="GravitateTo" Width="120"/>
+                    <TextBox Text="{Binding Selected.GravitateText}" Width="160"/>
+                </StackPanel>
+
+                <!-- Detect -->
+                <StackPanel Orientation="Horizontal" Spacing="8">
+                    <TextBlock Text="Detect" Width="120"/>
+                    <ComboBox ItemsSource="{Binding DetectModes}"
+                              SelectedItem="{Binding Selected.Detect}"
+                              Width="160"/>
+                </StackPanel>
+
+                <!-- OverrideTargetDuration -->
+                <StackPanel Orientation="Horizontal" Spacing="8">
+                    <TextBlock Text="Target Duration" Width="120"/>
+                    <NumericUpDown Value="{Binding Selected.OverrideTargetDuration}" Width="120"/>
+                </StackPanel>
+
+                <!-- ForceFixed -->
+                <CheckBox Content="Force Fixed Duration"
+                          IsChecked="{Binding Selected.ForceFixed}"/>
+
+                <!-- Debug -->
+                <CheckBox Content="Debug Mode"
+                          IsChecked="{Binding Selected.Debug}"/>
+
+                <!-- Parameters dictionary -->
+                <TextBlock Text="Advanced Parameters" FontSize="10" Margin="0,10,0,0" FontWeight="Bold"/>
+
+                <DataGrid ItemsSource="{Binding Selected.ParametersList}"
+                                AutoGenerateColumns="False"
+                                HeadersVisibility="Column"
+                                Margin="0,0,20,0"
+                                Height="160">
+
+                    <DataGrid.Columns>
+
+                        <DataGridTemplateColumn Header="Key" Width="*">
+                            <DataGridTemplateColumn.CellTemplate>
+                                <DataTemplate>
+                                    <TextBlock Text="{Binding Key}"
+                                               FontSize="10"
+                                               TextTrimming="CharacterEllipsis"
+                                               ToolTip.Tip="{Binding Key}">
+                                    </TextBlock>
+                                </DataTemplate>
+                            </DataGridTemplateColumn.CellTemplate>
+                        </DataGridTemplateColumn>
+
+                        <DataGridTemplateColumn Header="Value" Width="2*">
+                            <DataGridTemplateColumn.CellTemplate>
+                                <DataTemplate>
+                                    <TextBlock Text="{Binding Value}"/>
+                                </DataTemplate>
+                            </DataGridTemplateColumn.CellTemplate>
+
+                            <DataGridTemplateColumn.CellEditingTemplate>
+                                <DataTemplate>
+                                    <TextBox Text="{Binding Value, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}"/>
+                                </DataTemplate>
+                            </DataGridTemplateColumn.CellEditingTemplate>
+                        </DataGridTemplateColumn>
+
+                    </DataGrid.Columns>
+                </DataGrid>
+
+
+                <!-- Passthrough -->
+                <StackPanel Orientation="Horizontal" Spacing="8">
+                    <TextBlock Text="Passthrough" Width="120"/>
+                    <TextBox Text="{Binding Selected.PassthroughText}" Width="260"/>
+                </StackPanel>
+
+                <StackPanel Orientation="Horizontal"
+                            HorizontalAlignment="Right"
+                            Spacing="8"
+                            Margin="0,10,0,0">
+
+                    <Button Content="Apply to Selected"
+                            Command="{Binding ApplyOverridesCommand}"/>
+
+                    <Button Content="Transform all"
+                            Background="#AA0000"
+                            Foreground="White"
+                            Command="{Binding TransformAllCommand}"/>
+
+                </StackPanel>
+
+
+            </StackPanel>
+        </ScrollViewer>
+    </Border>
+</UserControl>

Splitter-UI/Views/InspectorPane.axaml.cs

@@ -0,0 +1,11 @@
+using Avalonia.Controls;
+
+namespace Splitter_UI.Views;
+
+public partial class InspectorPane : UserControl
+{
+    public InspectorPane()
+    {
+        InitializeComponent();
+    }
+}

Splitter-UI/Views/JobListItemView.axaml

@@ -0,0 +1,50 @@
+<UserControl
+    x:Class="Splitter_UI.Views.JobListItemView"
+    xmlns="https://github.com/avaloniaui"
+    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+    xmlns:vm="clr-namespace:Splitter_UI.ViewModels"
+    xmlns:conv="clr-namespace:Splitter_UI.Converters"
+    x:DataType="vm:JobViewModel">
+
+    <UserControl.Resources>
+        <conv:RotationAngleToIconConverter x:Key="RotationAngleToIconConverter"/>
+        <conv:ActionToIconConverter x:Key="ActionToIconConverter"/>
+    </UserControl.Resources>
+
+    <Border Margin="0"
+            Padding="0"
+            CornerRadius="4"
+            Background="#2A2A2A">
+
+        <StackPanel MinWidth="160" MaxWidth="160">
+
+            <Border Width="160" Height="90" ClipToBounds="True">
+                <Grid>
+                    <Image Source="{Binding Thumbnail}"
+                           Stretch="UniformToFill"
+                           HorizontalAlignment="Center"
+                           VerticalAlignment="Center"/>
+
+                    <TextBlock FontFamily="{StaticResource FontAwesome}"
+                               Text="{Binding Rotate, Converter={StaticResource ActionToIconConverter}}"
+                               FontSize="12"
+                               HorizontalAlignment="Right"
+                               Foreground="LimeGreen"/>
+
+                    <TextBlock FontFamily="{StaticResource FontAwesome}"
+                               Text="{Binding Rotate, Converter={StaticResource RotationAngleToIconConverter}}"
+                               FontSize="12"
+                               HorizontalAlignment="Left"
+                               Foreground="LimeGreen"/>
+                </Grid>
+            </Border>
+
+            <TextBlock Text="{Binding FileName}"
+                       TextWrapping="Wrap"
+                       Margin="0,6,0,0"
+                       FontSize="10"/>
+
+        </StackPanel>
+
+    </Border>
+</UserControl>

Splitter-UI/Views/JobListItemView.axaml.cs

@@ -0,0 +1,12 @@
+using Avalonia.Controls;
+
+namespace Splitter_UI.Views;
+
+public partial class JobListItemView : UserControl
+{
+    public JobListItemView()
+    {
+        InitializeComponent();
+    }
+}
+

Splitter-UI/Views/LogPane.axaml

@@ -0,0 +1,34 @@
+<UserControl
+    xmlns="https://github.com/avaloniaui"
+    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+    x:Class="Splitter_UI.Views.LogPane"
+    xmlns:conv="clr-namespace:Splitter_UI.Converters"
+    xmlns:vm="clr-namespace:Splitter_UI.ViewModels"
+    x:DataType="vm:LogPaneViewModel">
+
+<UserControl.Resources>
+    <conv:ConsoleColorToBrushConverter x:Key="ConsoleColorToBrushConverter"/>
+</UserControl.Resources>
+
+    <Border Background="#111" Padding="8">
+        <ScrollViewer x:Name="Scroller">
+            <ItemsControl ItemsSource="{Binding Logs}">
+                <ItemsControl.ItemTemplate>
+                    <DataTemplate x:DataType="vm:LogEntry">
+                        <StackPanel Orientation="Horizontal">
+                            <TextBlock Text="[" FontFamily="Consolas" FontSize="12"/>
+                            <TextBlock Text="{Binding Prefix}"
+                                       FontFamily="Consolas"
+                                       FontSize="12"
+                                       Foreground="{Binding Color, Converter={StaticResource ConsoleColorToBrushConverter}}"/>
+                            <TextBlock Text="] " FontFamily="Consolas" FontSize="12"/>
+                            <TextBlock Text="{Binding Message}"
+                                       FontFamily="Consolas"
+                                       FontSize="12"/>
+                        </StackPanel>
+                    </DataTemplate>
+                </ItemsControl.ItemTemplate>
+            </ItemsControl>
+        </ScrollViewer>
+    </Border>
+</UserControl>

Splitter-UI/Views/LogPane.axaml.cs

@@ -0,0 +1,31 @@
+using Avalonia.Controls;
+using Avalonia.Threading;
+
+namespace Splitter_UI.Views;
+
+public partial class LogPane : UserControl
+{
+    public LogPane()
+    {
+        InitializeComponent();
+
+        // When DataContext changes, subscribe to collection changes
+        this.DataContextChanged += (_, _) =>
+        {
+            if (DataContext is LogPaneViewModel vm)
+            {
+                vm.Logs.CollectionChanged += (_, _) => ScrollToEnd();
+            }
+        };
+    }
+
+    private void ScrollToEnd()
+    {
+        // Must run after layout pass
+        Dispatcher.UIThread.Post(() =>
+        {
+            if (Scroller != null)
+                Scroller.ScrollToEnd();
+        }, DispatcherPriority.Background);
+    }
+}

Splitter-UI/Views/MainWindow.axaml

@@ -0,0 +1,55 @@
+<Window
+    xmlns="https://github.com/avaloniaui"
+    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+    xmlns:views="clr-namespace:Splitter_UI.Views"
+    xmlns:vm="clr-namespace:Splitter_UI.ViewModels"
+    xmlns:conv="clr-namespace:Splitter_UI.Converters"
+    x:Class="Splitter_UI.Views.MainWindow"
+    x:DataType="vm:MainViewModel"
+    x:Name="Root"
+    Width="1400"
+    Height="950"
+    Title="Splitter UI"
+    Icon="avares://Splitter-UI/Assets/splitter.png">
+
+    <Window.Resources>
+        <conv:BoolInvertConverter x:Key="BoolInvertConverter"/>
+    </Window.Resources>
+
+    <DockPanel>
+
+        <!-- Status Bar -->
+        <views:StatusBarView DockPanel.Dock="Bottom"
+                             DataContext="{Binding StatusBar}" />
+
+        <!-- Log Pane -->
+        <views:LogPane DockPanel.Dock="Bottom" Height="150"
+                       DataContext="{Binding LogPane}" />
+
+        <Grid>
+            <!-- Main Content -->
+            <Grid ColumnDefinitions="2*,3*,430" IsVisible="{Binding TransformMode, Converter={StaticResource BoolInvertConverter}}">
+
+                <!-- File List -->
+                <views:FileListView Grid.Column="0"
+                                    DataContext="{Binding FileList}" />
+
+                <!-- Preview -->
+                <views:PreviewPane Grid.Column="1"
+                                   DataContext="{Binding Preview}" />
+
+                <!-- Inspector -->
+                <views:InspectorPane Grid.Column="2"
+                                     DataContext="{Binding Inspector}" />
+
+            </Grid>
+            
+            <!-- Progress view (replaces entire grid) -->
+            <views:ProgressView
+                DataContext="{Binding Progress}"
+                IsVisible="{Binding #Root.DataContext.TransformMode}"/>
+        </Grid>
+
+    </DockPanel>
+</Window>
+

Splitter-UI/Views/MainWindow.axaml.cs

@@ -0,0 +1,12 @@
+using Avalonia.Controls;
+
+namespace Splitter_UI.Views;
+
+public partial class MainWindow : Avalonia.Controls.Window
+{
+    public MainViewModel Data { get; } = null!; // set by DI
+    public MainWindow()
+    {
+        InitializeComponent();
+    }
+}

Splitter-UI/Views/PreviewCanvas.cs

@@ -0,0 +1,478 @@
+using System.ComponentModel;
+using Avalonia;
+using Avalonia.Controls;
+using Avalonia.Input;
+using Avalonia.Media;
+using Avalonia.Threading;
+
+namespace Splitter_UI.Views;
+
+public sealed class PreviewCanvas : Control
+{
+    public static readonly StyledProperty<PreviewData?> PreviewProperty =
+        AvaloniaProperty.Register<PreviewCanvas, PreviewData?>(nameof(Preview));
+    public static readonly StyledProperty<Point2f?> SarProperty =
+        AvaloniaProperty.Register<PreviewCanvas, Point2f?>(nameof(Sar));
+    public static readonly StyledProperty<int> RotateAngleProperty =
+        AvaloniaProperty.Register<PreviewCanvas, int>(nameof(RotateAngle));
+    public static readonly StyledProperty<Point2f> GravitateToProperty =
+        AvaloniaProperty.Register<PreviewCanvas, Point2f>(nameof(GravitateTo));
+
+    public PreviewData? Preview
+    {
+        get => GetValue(PreviewProperty);
+        set => SetValue(PreviewProperty, value);
+    }
+
+    public Point2f? Sar
+    {
+        get => GetValue(SarProperty);
+        set => SetValue(SarProperty, value);
+    }
+
+    public int RotateAngle
+    {
+        get => GetValue(RotateAngleProperty);
+        set => SetValue(RotateAngleProperty, value);
+    }
+
+    // GravitateTo is normalized (0..1)
+    public Point2f GravitateTo
+    {
+        get => GetValue(GravitateToProperty);
+        set => SetValue(GravitateToProperty, value);
+    }
+
+    private bool           _dragging;
+    private Avalonia.Point _dragStartCanvas;
+    private Point2f        _dragStartValue;
+
+    static PreviewCanvas()
+    {
+        PreviewProperty.Changed.AddClassHandler<PreviewCanvas>(
+            (canvas, args) =>
+                canvas.OnPreviewChanged(args.OldValue as PreviewData,
+                                        args.NewValue as PreviewData));
+    }
+
+    public PreviewCanvas()
+    {
+        PointerPressed += OnPointerPressed;
+        PointerMoved += OnPointerMoved;
+        PointerReleased += OnPointerReleased;
+    }
+
+    private void OnPreviewChanged(PreviewData? oldValue, PreviewData? newValue)
+    {
+        if (oldValue is INotifyPropertyChanged oldNotify)
+            oldNotify.PropertyChanged -= PreviewPropertyChanged;
+
+        if (newValue is INotifyPropertyChanged newNotify)
+            newNotify.PropertyChanged += PreviewPropertyChanged;
+
+        Dispatcher.UIThread.Post(InvalidateVisual, DispatcherPriority.Render);
+    }
+
+    private void PreviewPropertyChanged(object? sender, PropertyChangedEventArgs e)
+    {
+        if (e.PropertyName == nameof(PreviewData.Frame) ||
+            e.PropertyName == nameof(PreviewData.DetectedBoxes) ||
+            e.PropertyName == nameof(PreviewData.CropRect))
+        {
+            Dispatcher.UIThread.Post(InvalidateVisual, DispatcherPriority.Render);
+        }
+    }
+
+    protected override Size MeasureOverride(Size availableSize) => availableSize;
+    protected override Size ArrangeOverride(Size finalSize) => finalSize;
+
+    // ------------------------------------------------------------
+    // Unified transform helpers
+    // ------------------------------------------------------------
+
+    private (double X, double Y) TransformPoint(
+        double x, double y,
+        double rawW, double rawH,
+        double offsetX, double offsetY,
+        double scale,
+        int rotate,
+        double pixelAspect)
+    {
+        switch (rotate)
+        {
+            case 90:
+                (x, y) = (rawH - y, x);
+                break;
+            case 180:
+                x = rawW - x;
+                y = rawH - y;
+                break;
+            case 270:
+                (x, y) = (y, rawW - x);
+                break;
+        }
+
+        if (rotate == 0 || rotate == 180)
+            x *= pixelAspect;
+        else
+            y *= pixelAspect;
+
+        var sx = offsetX + x * scale;
+        var sy = offsetY + y * scale;
+
+        return (sx, sy);
+    }
+
+    private Rect TransformRect(
+        double x, double y, double w, double h,
+        double rawW, double rawH,
+        double offsetX, double offsetY,
+        double scale,
+        int rotate,
+        double pixelAspect)
+    {
+        switch (rotate)
+        {
+            case 90:
+                (x, y) = (rawH - (y + h), x);
+                (w, h) = (h, w);
+                break;
+
+            case 180:
+                x = rawW - (x + w);
+                y = rawH - (y + h);
+                break;
+
+            case 270:
+                (x, y) = (y, rawW - (x + w));
+                (w, h) = (h, w);
+                break;
+        }
+
+        if (rotate == 0 || rotate == 180)
+        {
+            x *= pixelAspect;
+            w *= pixelAspect;
+        }
+        else
+        {
+            y *= pixelAspect;
+            h *= pixelAspect;
+        }
+
+        return new Rect(
+            offsetX + x * scale,
+            offsetY + y * scale,
+            w * scale,
+            h * scale);
+    }
+
+    // ------------------------------------------------------------
+    // Hit test for gravitate point (normalized)
+    // ------------------------------------------------------------
+
+    private bool HitGravitate(Avalonia.Point p, out Point2f value)
+    {
+        value = default;
+
+        var preview = Preview;
+        if (preview?.Frame is null)
+            return false;
+
+        var g = GravitateTo;
+
+        var rawW = preview.Frame.PixelSize.Width;
+        var rawH = preview.Frame.PixelSize.Height;
+
+        // normalized → pixel
+        double px = g.X * rawW;
+        double py = g.Y * rawH;
+
+        var rotate = RotateAngle;
+        var sar = Sar ?? new Point2f(1, 1);
+        var pixelAspect = sar.X / sar.Y;
+
+        var dispW = Bounds.Width;
+        var dispH = Bounds.Height;
+
+        double displayW, displayH;
+        if (rotate == 0 || rotate == 180)
+        {
+            displayW = rawW * pixelAspect;
+            displayH = rawH;
+        }
+        else
+        {
+            displayW = rawW;
+            displayH = rawH * pixelAspect;
+        }
+
+        var scale = Math.Min(dispW / displayW, dispH / displayH);
+        var offsetX = (dispW - displayW * scale) / 2;
+        var offsetY = (dispH - displayH * scale) / 2;
+
+        var (cx, cy) = TransformPoint(
+            px, py,
+            rawW, rawH,
+            offsetX, offsetY,
+            scale,
+            rotate,
+            pixelAspect);
+
+        const double radius = 10;
+        var hit = (p.X - cx) * (p.X - cx) + (p.Y - cy) * (p.Y - cy) <= radius * radius;
+
+        if (hit)
+            value = g;
+
+        return hit;
+    }
+
+    // ------------------------------------------------------------
+    // Pointer events
+    // ------------------------------------------------------------
+
+    private void OnPointerPressed(object? sender, PointerPressedEventArgs e)
+    {
+        var p = e.GetPosition(this);
+
+        if (HitGravitate(p, out var g))
+        {
+            _dragging = true;
+            _dragStartCanvas = p;
+            _dragStartValue = g; // normalized
+            e.Pointer.Capture(this);
+        }
+    }
+
+    private void OnPointerMoved(object? sender, PointerEventArgs e)
+    {
+        if (!_dragging || Preview?.Frame is null)
+            return;
+
+        var p = e.GetPosition(this);
+        var dxCanvas = p.X - _dragStartCanvas.X;
+        var dyCanvas = p.Y - _dragStartCanvas.Y;
+
+        var preview = Preview;
+        var rawW = preview.Frame.PixelSize.Width;
+        var rawH = preview.Frame.PixelSize.Height;
+
+        var rotate = RotateAngle;
+        var sar = Sar ?? new Point2f(1, 1);
+        var pixelAspect = sar.X / sar.Y;
+
+        var dispW = Bounds.Width;
+        var dispH = Bounds.Height;
+
+        double displayW, displayH;
+        if (rotate == 0 || rotate == 180)
+        {
+            displayW = rawW * pixelAspect;
+            displayH = rawH;
+        }
+        else
+        {
+            displayW = rawW;
+            displayH = rawH * pixelAspect;
+        }
+
+        var scale = Math.Min(dispW / displayW, dispH / displayH);
+
+        double dx = dxCanvas / scale;
+        double dy = dyCanvas / scale;
+
+        if (rotate == 0 || rotate == 180)
+            dx /= pixelAspect;
+        else
+            dy /= pixelAspect;
+
+        // start normalized → pixel
+        double gx = _dragStartValue.X * rawW + dx;
+        double gy = _dragStartValue.Y * rawH + dy;
+
+        switch (rotate)
+        {
+            case 90:
+                (gx, gy) = (gy, rawH - gx);
+                break;
+            case 180:
+                gx = rawW - gx;
+                gy = rawH - gy;
+                break;
+            case 270:
+                (gx, gy) = (rawW - gy, gx);
+                break;
+        }
+
+        // pixel → normalized
+        var nx = (float)(gx / rawW);
+        var ny = (float)(gy / rawH);
+
+        if (nx < 0) nx = 0;
+        if (ny < 0) ny = 0;
+        if (nx > 1) nx = 1;
+        if (ny > 1) ny = 1;
+
+        GravitateTo = new Point2f(nx, ny);
+
+        Dispatcher.UIThread.Post(InvalidateVisual, DispatcherPriority.Render);
+    }
+
+    private void OnPointerReleased(object? sender, PointerReleasedEventArgs e)
+    {
+        if (_dragging)
+        {
+            _dragging = false;
+            e.Pointer.Capture(null);
+        }
+    }
+
+    // ------------------------------------------------------------
+    // Overlay renderers
+    // ------------------------------------------------------------
+
+    private void RenderCropRectangle(
+        DrawingContext context,
+        PreviewData preview,
+        double rawW, double rawH,
+        double offsetX, double offsetY,
+        double scale,
+        int rotate,
+        double pixelAspect)
+    {
+        if (preview.CropRect is not { } crop)
+            return;
+
+        var rr = TransformRect(
+            crop.X, crop.Y, crop.Width, crop.Height,
+            rawW, rawH,
+            offsetX, offsetY,
+            scale,
+            rotate,
+            pixelAspect);
+
+        var pen = new Pen(Brushes.Yellow, 2);
+        context.DrawRectangle(null, pen, rr);
+    }
+
+    private void RenderGravitateTo(
+        DrawingContext context,
+        PreviewData preview,
+        double rawW, double rawH,
+        double offsetX, double offsetY,
+        double scale,
+        int rotate,
+        double pixelAspect)
+    {
+        var g = GravitateTo;
+
+        // normalized → pixel
+        double px = g.X * rawW;
+        double py = g.Y * rawH;
+
+        var (sx, sy) = TransformPoint(
+            px, py,
+            rawW, rawH,
+            offsetX, offsetY,
+            scale,
+            rotate,
+            pixelAspect);
+
+        const double radius = 10;
+
+        var circle = new EllipseGeometry(
+            new Rect(sx - radius, sy - radius, radius * 2, radius * 2));
+
+        var pen = new Pen(Brushes.Yellow, 2);
+        var brush = Brushes.Yellow;
+
+        context.DrawGeometry(brush, pen, circle);
+    }
+
+    private void RenderDetectedBoxes(
+        DrawingContext context,
+        PreviewData preview,
+        double rawW, double rawH,
+        double offsetX, double offsetY,
+        double scale,
+        int rotate,
+        double pixelAspect)
+    {
+        if (preview.DetectedBoxes is not { Count: > 0 })
+            return;
+
+        var pen = new Pen(Brushes.Lime, 2);
+
+        foreach (var r in preview.DetectedBoxes)
+        {
+            var rr = TransformRect(
+                r.X, r.Y, r.Width, r.Height,
+                rawW, rawH,
+                offsetX, offsetY,
+                scale,
+                rotate,
+                pixelAspect);
+
+            context.DrawRectangle(null, pen, rr);
+        }
+    }
+
+    // ------------------------------------------------------------
+    // Main Render
+    // ------------------------------------------------------------
+
+    public override void Render(DrawingContext context)
+    {
+        var preview = Preview;
+        if (preview?.Frame is null)
+            return;
+
+        var frame = preview.Frame;
+        var rawW = frame.PixelSize.Width;
+        var rawH = frame.PixelSize.Height;
+
+        var dispW = Bounds.Width;
+        var dispH = Bounds.Height;
+
+        if (dispW <= 0 || dispH <= 0)
+            return;
+
+        var rotate = RotateAngle;
+
+        var sar = Sar ?? new Point2f(1, 1);
+        var sarX = sar.X <= 0 ? 1 : sar.X;
+        var sarY = sar.Y <= 0 ? 1 : sar.Y;
+        var pixelAspect = sarX / sarY;
+
+        double displayW, displayH;
+
+        if (rotate == 0 || rotate == 180)
+        {
+            displayW = rawW * pixelAspect;
+            displayH = rawH;
+        }
+        else
+        {
+            displayW = rawW;
+            displayH = rawH * pixelAspect;
+        }
+
+        var scale = Math.Min(dispW / displayW, dispH / displayH);
+
+        var scaledW = displayW * scale;
+        var scaledH = displayH * scale;
+
+        var offsetX = (dispW - scaledW) / 2;
+        var offsetY = (dispH - scaledH) / 2;
+
+        context.DrawImage(
+            frame,
+            new Rect(0, 0, rawW, rawH),
+            new Rect(offsetX, offsetY, scaledW, scaledH));
+
+        RenderDetectedBoxes(context, preview, rawW, rawH, offsetX, offsetY, scale, rotate, pixelAspect);
+        RenderCropRectangle(context, preview, rawW, rawH, offsetX, offsetY, scale, rotate, pixelAspect);
+        RenderGravitateTo(context, preview, rawW, rawH, offsetX, offsetY, scale, rotate, pixelAspect);
+    }
+}

Splitter-UI/Views/PreviewPane.axaml

@@ -0,0 +1,60 @@
+<UserControl
+    xmlns="https://github.com/avaloniaui"
+    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+    xmlns:vm="clr-namespace:Splitter_UI.ViewModels"
+    xmlns:local="clr-namespace:Splitter_UI.Views"
+    x:Class="Splitter_UI.Views.PreviewPane"
+    x:DataType="vm:PreviewPaneViewModel">
+
+    <Border Background="#202020" Padding="10">
+        <Grid RowDefinitions="*,Auto">
+
+            <local:PreviewCanvas
+                Grid.Row="0"
+                Preview="{Binding Preview}"
+                Sar="{Binding Sar}"
+                RotateAngle="{Binding Rotate}"
+                GravitateTo="{Binding GravitateTo, Mode=TwoWay}"/>
+
+            <Grid Grid.Row="1"
+                  ColumnDefinitions="Auto,*,Auto"
+                  Margin="0,10,0,0">
+
+                <Button Grid.Column="0"
+                        HorizontalAlignment="Left"
+                        Width="24" Height="24"
+                        Padding="0"
+                        Margin="0,0,5,0"
+                        Command="{Binding Selected.StepBackwardCommand}">
+                    <TextBlock FontFamily="{StaticResource FontAwesome}"
+                               Text="&#xf048;"
+                               FontSize="12"
+                               VerticalAlignment="Center"
+                               HorizontalAlignment="Center" />
+                </Button>
+
+                <Slider Grid.Column="1"
+                        Minimum="0"
+                        Maximum="{Binding Selected.DurationSeconds}"
+                        Value="{Binding Selected.SliderLiveValue, Mode=TwoWay}"
+                        Margin="5,0,5,0" />
+
+                <Button Grid.Column="2"
+                        HorizontalAlignment="Right"
+                        Width="24" Height="24"
+                        Padding="0"
+                        Margin="5,0,0,0"
+                        Command="{Binding Selected.StepForwardCommand}">
+                    <TextBlock FontFamily="{StaticResource FontAwesome}"
+                               Text="&#xf051;"
+                               FontSize="12"
+                               VerticalAlignment="Center"
+                               HorizontalAlignment="Center" />
+                </Button>
+
+            </Grid>
+
+        </Grid>
+    </Border>
+</UserControl>
+

Splitter-UI/Views/PreviewPane.axaml.cs

@@ -0,0 +1,12 @@
+using Avalonia.Controls;
+
+namespace Splitter_UI.Views;
+
+public partial class PreviewPane : UserControl
+{
+    public PreviewPane()
+    {
+        InitializeComponent();
+    }
+
+}

Splitter-UI/Views/ProgressView.axaml

@@ -0,0 +1,63 @@
+<UserControl
+    x:Class="Splitter_UI.Views.ProgressView"
+    xmlns="https://github.com/avaloniaui"
+    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+    xmlns:vm="clr-namespace:Splitter_UI.ViewModels"
+    x:DataType="vm:ProgressViewModel">
+
+    <Grid RowDefinitions="*,Auto" Background="#111">
+
+        <!-- Processes list -->
+        <ItemsControl Grid.Row="0" ItemsSource="{Binding Processes}">
+            <ItemsControl.ItemTemplate>
+                <DataTemplate x:DataType="vm:ProgressInfo">
+                    <Grid ColumnDefinitions="2*,3*,Auto,Auto"
+                          Margin="0,2">
+
+                        <TextBlock Grid.Column="0"
+                                   Text="{Binding Name}"
+                                   VerticalAlignment="Center"
+                                   FontSize="12"/>
+
+                        <ProgressBar Grid.Column="1"
+                                     Height="12"
+                                     Minimum="0"
+                                     Maximum="1"
+                                     Value="{Binding Progress}"
+                                     Margin="8,0"/>
+
+                        <TextBlock Grid.Column="2"
+                                   Width="70"
+                                   Text="{Binding Eta, StringFormat={}{0:hh\\:mm\\:ss}}"
+                                   VerticalAlignment="Center"
+                                   Margin="12,0"
+                                   FontSize="12"/>
+
+                        <TextBlock Grid.Column="3"
+                                   Width="70"
+                                   Text="{Binding Speed, StringFormat={}{0:0.00}}"
+                                   VerticalAlignment="Center"
+                                   Margin="12,0"
+                                   FontSize="12"/>
+
+                    </Grid>
+                </DataTemplate>
+            </ItemsControl.ItemTemplate>
+        </ItemsControl>
+
+        <!-- Bottom-right Cancel button -->
+        <StackPanel Grid.Row="1"
+                    Orientation="Horizontal"
+                    HorizontalAlignment="Right"
+                    Margin="0,12,0,0">
+
+            <Button Content="Cancel"
+                    Background="#700000"
+                    Foreground="White"
+                    Padding="12,6"
+                    Margin="0,0,10,10"
+                    Command="{Binding CancelCommand}"/>
+        </StackPanel>
+
+    </Grid>
+</UserControl>

Splitter-UI/Views/ProgressView.axaml.cs

@@ -0,0 +1,12 @@
+using Avalonia.Controls;
+
+namespace Splitter_UI.Views;
+
+public partial class ProgressView : UserControl
+{
+    public ProgressView()
+    {
+        InitializeComponent();
+    }
+}
+

Splitter-UI/Views/StatusBarView.axaml

@@ -0,0 +1,24 @@
+<UserControl
+    xmlns="https://github.com/avaloniaui"
+    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
+    x:Class="Splitter_UI.Views.StatusBarView"
+    xmlns:vm="clr-namespace:Splitter_UI.ViewModels"
+    x:DataType="vm:StatusBarViewModel">
+
+    <Border Padding="4" Background="{DynamicResource ThemeBackgroundBrush}">
+        <Grid ColumnDefinitions="*,Auto,Auto" ColumnSpacing="8">
+            <TextBlock Grid.Column="0"
+                       VerticalAlignment="Center"
+                       Text="{Binding StatusText}" />
+
+            <ProgressBar Grid.Column="1"
+                         Width="200"
+                         Height="16"
+                         Minimum="0"
+                         Maximum="1"
+                         VerticalAlignment="Center"
+                         Value="{Binding Percent}" />
+
+        </Grid>
+    </Border>
+</UserControl>

Splitter-UI/Views/StatusBarView.axaml.cs

@@ -0,0 +1,11 @@
+using Avalonia.Controls;
+
+namespace Splitter_UI.Views;
+
+public partial class StatusBarView : UserControl
+{
+    public StatusBarView()
+    {
+        InitializeComponent();
+    }
+}

Splitter-UI/app.manifest

@@ -0,0 +1,18 @@
+<?xml version="1.0" encoding="utf-8"?>
+<assembly manifestVersion="1.0" xmlns="urn:schemas-microsoft-com:asm.v1">
+  <!-- This manifest is used on Windows only.
+       Don't remove it as it might cause problems with window transparency and embedded controls.
+       For more details visit https://learn.microsoft.com/en-us/windows/win32/sbscs/application-manifests -->
+  <assemblyIdentity version="1.0.0.0" name="Splitter_UI.Desktop"/>
+
+  <compatibility xmlns="urn:schemas-microsoft-com:compatibility.v1">
+    <application>
+      <!-- A list of the Windows versions that this application has been tested on
+           and is designed to work with. Uncomment the appropriate elements
+           and Windows will automatically select the most compatible environment. -->
+
+      <!-- Windows 10 -->
+      <supportedOS Id="{8e0f7a12-bfb3-4fe8-b9a5-48fd50a15a9a}" />
+    </application>
+  </compatibility>
+</assembly>

splitter-cli/CommandLine.cs

@@ -1,52 +1,14 @@
 using System.Globalization;
+using splitter.util;
 
 namespace splitter;
 
-public class SingleJob
-{
-    public string                     InputFile              { get; set; } = null!;
-    public string                     OutputFolder           { get; set; } = null!;
-    public (int width, int height)?   Crop                   { get; set; }
-    public Point2f?                   GravitateTo            { get; set; }
-    public string?                    Mask                   { get; set; }
-    public bool                       Debug                  { get; set; }
-    public string?                    Detect                 { get; set; }
-    public double?                    OverrideTargetDuration { get; set; }
-    public string[]                   Passthrough            { get; set; } = [];
-    public bool                       PlainText              { get; set; }
-    public bool                       EstimateOnly           { get; set; }
-    public bool                       ForceFixed             { get; set; }
-    public bool                       SingleThreaded         { get; set; }
-    public int?                       Rotate                 { get; set; }
-    public bool                       RotateAuto             { get; set; }
-    public Dictionary<string, string> Parameters             { get; set; } = [];
-
-    public void Override<T>(ref T member, string name)
-    {
-        if (!Parameters.TryGetValue(name, out var raw))
-            return;
-
-        try
-        {
-            // Convert.ChangeType handles int, float, double, etc.
-            var converted = (T)Convert.ChangeType(
-            raw,
-            typeof(T),
-            CultureInfo.InvariantCulture
-        );
-
-            member = converted;
-        }
-        catch
-        {
-            Console.WriteLine($"Invalid value for parameter '{name}': {raw}");
-        }
-    }
-
-}
-
 public sealed class CommandLine
 {
+    // Default vertical Full HD for YouTube Shorts
+    public const int DefaultW = 607;
+    public const int DefaultH = 1080;
+
     public SingleJob Master { get; } = new SingleJob();
     public SingleJob[] Jobs { get; }
 
@@ -272,13 +234,9 @@ public sealed class CommandLine
 
     private static (int width, int height)? ParseCrop(string v)
     {
-        // Default vertical Full HD for YouTube Shorts
-        const int defaultW = 607;
-        const int defaultH = 1080;
-
         // Empty or whitespace → default crop
         if (string.IsNullOrWhiteSpace(v))
-            return (defaultW, defaultH);
+            return (DefaultW, DefaultH);
 
         var s = v.Trim().ToLowerInvariant();
 

splitter-cli/GlobalUsing.cs

@@ -0,0 +1,5 @@
+global using OpenCvSharp;
+global using splitter.algo;
+global using splitter.probe;
+global using splitter.tui;
+

splitter-cli/IJobProcessor.cs

@@ -0,0 +1,7 @@
+namespace splitter;
+
+public interface IJobProcessor
+{
+    Task<List<SingleTask>> GenerateJobs(SingleJob job, bool estimateOnly, CancellationToken token);
+    Task<bool> ProcessJobs(List<SingleTask> tasks, bool singleThreaded, CancellationToken token);
+}

splitter-cli/ISegmentProcessor.cs

@@ -1,6 +0,0 @@
-namespace splitter;
-
-public interface ISegmentProcessor
-{
-    Task ProcessSegment( SingleTask job );
-}

splitter-cli/JobProcessor.cs

@@ -0,0 +1,227 @@
+using System.Collections.Concurrent;
+using System.Diagnostics;
+
+namespace splitter;
+
+public class JobProcessor(ILogger logger) : LoggingBase(logger, 0), IJobProcessor
+{
+    public async Task<List<SingleTask>> GenerateJobs(SingleJob job, bool estimateOnly, CancellationToken token)
+    {
+        var baseName = Path.GetFileNameWithoutExtension(job.InputFile);
+
+        if (!File.Exists(job.InputFile))
+        {
+            LogError($"{baseName}: Input file not found.");
+            return [];
+        }
+
+        if (!Directory.Exists(job.OutputFolder))
+            Directory.CreateDirectory(job.OutputFolder);
+
+        if (token.IsCancellationRequested)
+            return [];
+
+        var info = await ProbeVideo.Probe(job.InputFile, job.RotateAuto, token);
+
+        if (token.IsCancellationRequested)
+            return [];
+
+        if (info.Duration <= 0)
+        {
+            LogError($"{baseName}: Could not read duration.");
+            return [];
+        }
+
+        var target = job.OverrideTargetDuration ?? 58.0;
+
+        int segments;
+        double segmentLength;
+
+        if (job.ForceFixed)
+        {
+            // Fixed chunk size, last one may be shorter
+            segments = (int)Math.Ceiling(info.Duration / target);
+            segmentLength = target;
+        }
+        else
+        {
+            // Equalized segments
+            segments = (int)Math.Ceiling(info.Duration / target);
+            segmentLength = info.Duration / segments;
+        }
+
+        LogInfo($"{baseName}: Duration {info.Duration:F2}s, {info.Width}x{info.Height} @ {info.Fps:F3}fps {info.Bitrate / 1024:F0}kbps," +
+            $" Target duration: {target:F2}s Segments: {segments} segment length: {segmentLength:F2}s {(job.ForceFixed ? " fixed" : "")}");
+
+        if (estimateOnly)
+            return [];
+
+        Func<int, ISegmentProcessor> processorFactory;
+        if (job.Crop != null)
+        {
+            processorFactory = i =>
+            {
+                IObjectDetector detector = job.Detect switch
+                {
+                    "face" => new UltraFaceDetector(_logger),
+                    "body" => new YoloOnnxObjectDetector(_logger),
+                    _      => throw new InvalidOperationException($"Unknown detector: {job.Detect}")
+                };
+                return new TrackingSplitter(i, detector, job, _logger);
+            };
+        }
+        else
+        {
+            processorFactory = i => new SimpleSplitter(i, _logger);
+        }
+
+        var jobs = Enumerable.Range(0, segments)
+            .Select(i => new SingleTask
+                (
+                    Job              : job,
+                    Info: info,
+                    OutputFileName   : BuildOutputFileName(job, i),
+                    SegmentIndex     : i,
+                    TotalSegments    : segments,
+                    SegmentStart     : i * segmentLength,
+                    SegmentLength    : (i == segments - 1)
+                        ? Math.Max(0.1, info.Duration - i * segmentLength)
+                                     : segmentLength,
+                    ProcessorFactory : processorFactory
+                )
+            )
+            .ToList();
+
+        return jobs;
+    }
+
+    public async Task<bool> ProcessJobs(List<SingleTask> tasks, bool singleThreaded, CancellationToken token)
+    {
+
+        if (singleThreaded)
+        {
+            LogInfo("Starting single-threaded splitting...");
+            await RunSingleThreaded(tasks, token);
+        }
+        else
+        {
+            LogInfo("Starting multi-threaded splitting...");
+            await RunMultiThreaded(tasks, token);
+        }
+
+        LogInfo("Done.");
+        return true;
+    }
+
+    private void LogProgress(double progress, TimeSpan eta, double speed) => _logger.DrawProgress("Total", 0, progress, eta, speed);
+
+    // -----------------------------
+    // ffprobe
+    // -----------------------------
+
+    // -----------------------------
+    // Multi-threaded splitting
+    // -----------------------------
+
+    private async Task RunMultiThreaded(List<SingleTask> jobs, CancellationToken token)
+    {
+        LogProgress(0.0, TimeSpan.Zero, 0.0);
+
+        var maxDegree = Math.Max(1, Environment.ProcessorCount / 2);
+
+        using var sem = new SemaphoreSlim(maxDegree);
+        var tasks = new List<Task>();
+
+        // Slot pool: 0..maxDegree-1
+        var freeSlots = new ConcurrentQueue<int>(Enumerable.Range(0, maxDegree));
+
+        var totalSegments     = jobs.Count;
+        var processedSegments = 0;
+        var totalDuration     = jobs.Sum(j => j.SegmentLength);
+        var sw                = Stopwatch.StartNew();
+
+        foreach (var job in jobs)
+        {
+            await sem.WaitAsync(token);
+
+            tasks.Add(Task.Run(async () =>
+            {
+                int slot = -1;
+
+                try
+                {
+                    // Acquire a slot ID
+                    while (!freeSlots.TryDequeue(out slot))
+                    {
+                        if ( token.IsCancellationRequested)
+                            return; 
+                        await Task.Yield();
+                    }
+                    await ProcessSegment(job, slot + 1, token);
+
+                    var processed = Interlocked.Increment(ref processedSegments);
+                    var elapsed   = sw.Elapsed;
+                    var eta       = TimeSpan.FromTicks(elapsed.Ticks * (totalSegments - processed) / processed);
+                    var speed     = (processed * totalDuration) / elapsed.TotalSeconds;
+                    LogProgress((double)processed / totalSegments, eta, speed);
+                }
+                finally
+                {
+                    // Return slot to pool
+                    if (slot >= 0)
+                        freeSlots.Enqueue(slot);
+
+                    sem.Release();
+                }
+            }));
+        }
+
+        await Task.WhenAll(tasks);
+    }
+
+
+    // -----------------------------
+    // Single-threaded splitting
+    // -----------------------------
+
+    private async Task RunSingleThreaded(List<SingleTask> jobs, CancellationToken token)
+    {
+        foreach (var job in jobs)
+        {
+            await ProcessSegment(job, 0, token);
+        }
+
+    }
+
+    private async Task ProcessSegment(SingleTask t, int slot, CancellationToken token)
+    {
+        var processor = t.ProcessorFactory(slot);
+        try
+        {
+            await processor.ProcessSegment(t, token);
+        }
+        finally
+        {
+            if (processor is IDisposable disposable)
+                disposable.Dispose();
+        }
+    }
+
+    private static string BuildOutputFileName(SingleJob job, int index)
+    {
+        string fileName;
+
+        fileName = Path.GetFileName(job.Mask ?? "[NAME]_seg[NN].[EXT]")
+            .Replace("[NAME]", Path.GetFileNameWithoutExtension(job.InputFile))
+            .Replace("[N]", index.ToString())
+            .Replace("[NN]", index.ToString("00"))
+            .Replace("[NNN]", index.ToString("000"))
+            .Replace("[NNNN]", index.ToString("0000"))
+            .Replace("[EXT]", Path.GetExtension(job.InputFile).TrimStart('.'))
+            ;
+
+        return Path.Combine(job.OutputFolder, fileName);
+    }
+
+
+}

splitter-cli/Point2f.cs

@@ -1,13 +0,0 @@
-namespace splitter;
-
-public struct Point2f
-{
-    public float X;
-    public float Y;
-
-    public Point2f(float x, float y)
-    {
-        X = x;
-        Y = y;
-    }
-}

splitter-cli/ProbeVideo.cs

@@ -1,108 +0,0 @@
-using System.Diagnostics;
-using System.Globalization;
-
-namespace splitter;
-
-public record VideoInfo(
-    double Duration,
-    int Width,
-    int Height,
-    double Fps,
-    double Bitrate,
-    int Rotation = 0
-);
-
-public static class ProbeVideo
-{
-    public static async Task<VideoInfo> Probe(SingleJob job)
-    {
-        var info = ProbeSize(job.InputFile);
-        if ( job.RotateAuto)
-        {
-            var rotation = await ProbeRotation(job, info.Duration);
-            info = info with { Rotation = rotation };
-        }
-
-        return info;
-    }
-
-    private static async Task<int> ProbeRotation(SingleJob job, double duration)
-    {
-        var rotation = await new VideoRotationSampler(job).DetectRotationAsync(job.InputFile, duration);
-        return rotation;
-    }
-
-    private static VideoInfo ProbeSize(string inputFile)
-    {
-        var args =
-        "-v error " +
-        "-select_streams v:0 " +
-        "-show_entries format=duration " +
-        "-show_entries stream=width,height,avg_frame_rate,bit_rate " +
-        "-of default=noprint_wrappers=1:nokey=0 " +   // <-- IMPORTANT: include keys
-        $"\"{inputFile}\"";
-
-        var psi = new ProcessStartInfo
-        {
-            FileName               = "ffprobe",
-            Arguments              = args,
-            RedirectStandardOutput = true,
-            RedirectStandardError  = true,
-            UseShellExecute        = false,
-            CreateNoWindow         = true
-        };
-
-        using var p = new Process { StartInfo = psi };
-        p.Start();
-
-        var duration = -1.0;
-        var width    = 0;
-        var height   = 0;
-        var fps      = 0.0;
-        var bitrate  = 0.0;
-
-        while (!p.StandardOutput.EndOfStream)
-        {
-            var line = p.StandardOutput.ReadLine()?.Trim();
-            if (string.IsNullOrWhiteSpace(line))
-                continue;
-
-            if (line.StartsWith("duration="))
-            {
-                var v = line.Substring("duration=".Length);
-                double.TryParse(v, NumberStyles.Any, CultureInfo.InvariantCulture, out duration);
-            }
-            else if (line.StartsWith("width="))
-            {
-                var v = line.Substring("width=".Length);
-                int.TryParse(v, NumberStyles.Integer, CultureInfo.InvariantCulture, out width);
-            }
-            else if (line.StartsWith("bit_rate="))
-            {
-                var v = line.Substring("bit_rate=".Length);
-                double.TryParse(v, NumberStyles.Float, CultureInfo.InvariantCulture, out bitrate);
-            }
-            else if (line.StartsWith("height="))
-            {
-                var v = line.Substring("height=".Length);
-                int.TryParse(v, NumberStyles.Integer, CultureInfo.InvariantCulture, out height);
-            }
-            else if (line.StartsWith("avg_frame_rate="))
-            {
-                var v = line.Substring("avg_frame_rate=".Length);
-                var parts = v.Split('/');
-                if (parts.Length == 2 &&
-                    double.TryParse(parts[0], NumberStyles.Float, CultureInfo.InvariantCulture, out var num) &&
-                    double.TryParse(parts[1], NumberStyles.Float, CultureInfo.InvariantCulture, out var den) &&
-                    den != 0)
-                {
-                    fps = num / den;
-                }
-            }
-        }
-
-        p.WaitForExit();
-
-        return new(duration, width, height, fps, bitrate);
-    }
-}

splitter-cli/README.md

@@ -0,0 +1,212 @@
+# Splitter
+
+Splitter is a high-performance command line tool for cutting one or more video files into equal or fixed-length segments using multi-threaded FFmpeg execution.
+It supports batch input, flexible duration formats, rotation, smart face/body-aware cropping, ETA and speed reporting, and both rich and plain-text terminal output.
+
+![Splitter](splitter.png)
+
+## Features
+
+- Multi-threaded FFmpeg splitting for maximum throughput
+- Equal or fixed-length segmentation
+- Batch input via file masks or list files
+- Smart cropping with face/body tracking
+- Rotation correction
+- ETA, speed, and progress display
+- FFmpeg passthrough for advanced control
+- [Potentially] Cross-platform (.NET 10)
+
+## Requirements
+
+- FFmpeg and FFprobe available in system PATH
+- .NET 10 Runtime or newer
+
+If you want to update model:
+
+- For face detection: [opencv_zoo/models/face_detection_yunet at main · opencv/opencv_zoo](https://github.com/opencv/opencv_zoo/tree/main/models/face_detection_yunet)
+- For body detection: [yolov8s.pt · Ultralytics/YOLOv8 at main](https://huggingface.co/Ultralytics/YOLOv8/blob/main/yolov8s.pt)
+
+To convert models from PyTorch to ONNX, you can use the following command:
+
+```python
+from ultralytics import YOLO
+
+model = YOLO("yolov8x.pt")
+model.export(format="onnx", opset=12, half=False)   # FP32 ONNX
+```
+
+## How It Works
+
+1. Reads total duration using ffprobe
+2. Parses target duration
+3. Computes number of segments
+4. If not forced, equalizes segment lengths
+5. Runs multiple FFmpeg processes in parallel
+6. Applies rotation, crop, and tracking if enabled
+7. Displays progress, ETA, and speed
+
+## Face Tracking vs Body Tracking
+
+Face tracking and body tracking serve different purposes, and Splitter supports both because each
+excels in different recording environments. When converting horizontal footage into vertical clips,
+the choice of detector determines how stable, reliable, and natural the automated camera motion will be.
+
+![Face vs Body Tracking](tracking.png)
+
+### Face Tracking Using UltraFace 320
+
+Splitter uses the UltraFace 320 ONNX model to perform lightweight, real-time face detection on each
+frame of the input video. The detector produces bounding boxes for visible faces, and the tracking
+system maintains a stable, smoothed target region across time. This is achieved by combining per-frame
+detections with temporal smoothing (EMA), dropout tolerance, and camera easing. The result is a
+continuous, stable crop window that follows the performer even when the face is partially occluded,
+briefly lost, or moving rapidly.
+
+During segmentation, the crop window is recalculated for every frame, ensuring that each output
+segment inherits the same smooth camera motion. This makes the vertical clips appear as if they
+were recorded with a dedicated portrait-oriented camera operator. The UltraFace 320 model is
+fast enough to run alongside multi-threaded FFmpeg splitting without becoming a bottleneck,
+making it suitable for long recordings and batch processing.
+
+### Benefits of Full-Body Detection Using YOLOv8s for Live Gig Recordings
+
+When recording concerts or live gigs, performers often move unpredictably, turn away from the
+camera, or become partially obscured by lighting, instruments, or stage effects.
+Full-body detection using a YOLOv8s ONNX model provides a more reliable tracking anchor than
+face detection alone. Because YOLOv8s can detect the entire human silhouette, the tracker
+maintains stable framing even when the face is not visible, when the performer is far from
+the camera, or when stage lighting makes facial features hard to detect. This produces vertical
+clips that feel intentional and professionally framed, with fewer sudden jumps or lost-tracking
+moments. For creators converting horizontal gig footage into short vertical clips for YouTube
+Shorts or TikTok, body-based tracking significantly improves consistency, reduces manual editing,
+and preserves the energy and motion of the performance.
+
+### Automated Camera Control
+
+Splitter includes an automated camera control system that simulates the behavior of a virtual
+camera operator when generating vertical crops from horizontal footage. The goal is to maintain
+smooth, intentional framing around the tracked subject, even when detections are noisy, intermittent,
+or temporarily lost.
+
+The controller receives object detections (face or body) and converts them into a stable crop
+window using a combination of Kalman filtering, exponential smoothing, dropout tolerance,
+and a three-state tracking model. The Kalman filter provides predictive motion smoothing,
+while the EMA factor blends the predicted position with the previous camera center to avoid jitter.
+The camera easing value controls how quickly the virtual camera follows the subject, producing
+natural-looking motion rather than abrupt jumps.
+
+When detections disappear, the controller enters one of two fallback modes. In LostFreeze mode,
+the camera holds its last known position for a configurable number of frames, preventing sudden
+jumps during brief occlusions. If the subject remains lost beyond that threshold, the controller
+transitions to LostDrift mode, slowly drifting the camera back toward a neutral center position.
+This prevents the crop from drifting off-screen and ensures that the output remains usable even
+when tracking fails. All positions are clamped to valid bounds, guaranteeing that the crop window
+never leaves the video frame.
+
+### Automatic rotation detection
+
+The rotation-estimation method is based on analyzing the distribution of gradient orientations within 
+a video frame. After converting the frame to grayscale, the algorithm computes horizontal and vertical 
+image gradients using Sobel operators and derives per-pixel gradient magnitudes and orientations. 
+These orientations are folded into the range [0, 180) and accumulated into a fixed-size, 
+magnitude-weighted histogram. The histogram represents the structural edge distribution of the frame, 
+independent of brightness fluctuations or local lighting artifacts. By comparing the total gradient
+energy concentrated near 0 degrees (vertical edges) with the energy near 90 degrees (horizontal edges), 
+the method determines whether the frame is more consistent with an upright or sideways orientation.
+
+This approach is designed for environments where brightness-based cues are unreliable, such as
+live concerts with strobe lights, LED walls, haze, and crowd movement. It relies solely on geometric 
+edge structure, which remains stable even under extreme lighting variation. The implementation is 
+optimized for high-throughput video processing: all intermediate Mats, buffers, and histograms are 
+preallocated, and pixel data is accessed directly through pointers to avoid per-frame memory 
+allocation. The method is intentionally biased toward the upright orientation, returning a sideways
+classification only when the horizontal-edge energy significantly exceeds the vertical-edge energy.
+
+## Usage
+
+```
+splitter [<input.mp4> ...] [options] [--] <ffmpeg passthrough>
+```
+
+Inputs may be provided directly, via `--file=...`, or using file masks such as `videos/*.mp4`.
+
+
+## Options
+
+Below is a clean, ASCII-only **options table** version of your content.
+All option names are preserved exactly, and descriptions are consolidated for clarity.
+
+---
+
+## Options
+
+| Option | Description |
+|--------|-------------|
+| **--out=<folder>** | Output folder for generated segments. Default: `<input folder>/Splitter`. |
+| **--file=<path>** | Input file list or file mask. If omitted, the first non-option argument is used as input. Examples: `--file=videos/*.mp4`, `--file=file_list.txt`. |
+| **--mask=<pattern>** | Custom output filename pattern. Default: `[NAME]_seg[NN].[EXT]`. Supports `[NAME]`, `[N]`, `[NN]`, `[NNN]`, `[NNNN]`, `[EXT]`. Example: `--mask="[NAME]_[NNNN].mp4"`. |
+| **--duration=<value>** | Override target segment duration. Formats: `Ns`, `NmMs`, `N`. Examples: `--duration=90s`, `--duration=2m30s`, `--duration=45`. Without `--force`: max 58 seconds, equalized across segments. |
+| **--force** | Use the duration exactly as provided. Last segment may be shorter. |
+| **--rotate=<degrees>** | Rotate video by 90, 180, or 270 degrees. Useful for correcting orientation metadata. |
+| **--rotate-auto** | Use automatic rotation detection. |
+| **--estimate** | Print calculated segment information and exit. No splitting is performed. |
+| **--crop[=<w:h>]** | Crop video to a target width and height with face/body tracking. Default: 607x1080. Ideal for Shorts, TikTok, Reels. |
+| **--detect=<name>** | Object detector for tracking. Values: `face` (UltraFace), `body` (YoloOnnx, default), `none` (center crop). |
+| **--gravitate=<x:y>** | Bias the crop window toward a normalized point in the frame. Example: `--gravitate=0.2:0.5`. |
+| **--text** | Use plain-text logging instead of the rich terminal UI. |
+| **--single-thread** | Disable parallel FFmpeg execution. Useful for debugging or low-resource systems. |
+| **--debug** | Show debug overlay during tracking. No cropping performed, but crop region shown. |
+| **-p:<name>=<value>** | Set custom parameters for the object detector. Example: `-p:confidence=0.5`. Defaults: DropoutToleranceFrames=20, EmaFactor=0.65, CameraEasing=0.03, LostFreezeFrames=60. |
+
+## FFmpeg Passthrough
+
+Anything after `--` is passed directly to FFmpeg.
+
+Example:
+```
+splitter video.mp4 --force --duration=45 -- -an -sn
+```
+
+## Input and Output Behavior
+
+- `input.mp4` may be a file mask (`videos/*.mp4`)
+- Output filenames follow the `--mask` pattern
+- Output folder defaults to `<input folder>/Splitter` unless overridden
+
+## Examples
+
+Split into equal 60-second segments:
+```
+splitter vertical-video.mp4
+```
+
+Split into equal 90-second segments:
+```
+splitter vertical-video.mp4 --duration=90s
+```
+
+Custom naming:
+```
+splitter vertical-video.mp4 --duration=2m30s --mask="[NAME]_[NNNN].mp4"
+```
+
+Estimate only:
+```
+splitter vertical-video.mp4 --estimate
+```
+
+Fixed 45-second segments with passthrough:
+```
+splitter vertical-video.mp4 --force --duration=45 -- -an -sn
+```
+
+Smart crop for Shorts:
+```
+splitter horizontal-video.mp4 --out=Cropped/ --crop
+```
+
+Batch processing with body tracking:
+```
+splitter --file=file_names.txt --out=Cropped/ --crop --detect=body
+```
+

splitter-cli/SimpleSplitter.cs

@@ -5,59 +5,96 @@ namespace splitter;
 
 public class SimpleSplitter(int segmentNo, ILogger logger) : LoggingBase(logger, segmentNo), ISegmentProcessor
 {
-    public async Task ProcessSegment(SingleTask job)
+    public async Task ProcessSegment(SingleTask job, CancellationToken token)
     {
-        string inputFile                     = job.Job.InputFile;
+        string inputFile  = job.Job.InputFile;
-        string outputFile                    = job.OutputFileName;
+        string outputFile = job.OutputFileName;
-        double start                         = job.SegmentStart;
+        double start      = job.SegmentStart;
-        double length                        = job.SegmentLength;
+        double length     = job.SegmentLength;
-        int videoWidth                       = job.Info.Width;
+
-        int videoHeight                      = job.Info.Height;
+        var rotation = GetRotationFilter(job.Job.Rotate);
-        double fps                           = job.Info.Fps;
-        string[] ffmpegPassthroughParameters = job.Job.Passthrough;
-        
-        var pass = ffmpegPassthroughParameters.Length > 0 ? string.Join(" ", ffmpegPassthroughParameters) : "";
 
         string args;
-        var rotation = GetRotationFilter(job.Job.Rotate);
+
         if (rotation == null)
         {
+            // Copy path: keep original SAR/DAR exactly as in source
             args =
                 $"-ss {start.ToString(CultureInfo.InvariantCulture)} " +
                 $"-i \"{inputFile}\" " +
                 $"-t {length.ToString(CultureInfo.InvariantCulture)} " +
-                $"-c copy {pass} \"{outputFile}\" -y";
+                $"-c copy {string.Join(" ", job.Job.Passthrough)} " +
+                $"\"{outputFile}\" -y";
         }
         else
         {
-            // Rotation → must re-encode
+            var sarArg = "";
+            var darArg = "";
+
+            var sar = job.Info.SampleAspectRatio; // e.g. "4:3"
+            if (sar != null)
+            {
+                // Rotation path: must re-encode and recompute DAR
+
+                long sarNum = Convert.ToInt64(job.Info.Sar.X);
+                long sarDen = Convert.ToInt64(job.Info.Sar.Y);
+
+                // After rotation, width/height swap
+                int w = job.Info.Width;
+                int h = job.Info.Height;
+
+                if (job.Job.Rotate == 90 || job.Job.Rotate == 270)
+                {
+                    (w, h) = (h, w);
+                }
+
+                // Compute DAR = (w * sarNum) : (h * sarDen)
+                var darNum = w * sarNum;
+                var darDen = h * sarDen;
+
+                // Reduce fraction
+                long Gcd(long a, long b)
+                {
+                    while (b != 0) (a, b) = (b, a % b);
+                    return a;
+                }
+                var g = Gcd(darNum, darDen);
+                darNum /= g;
+                darDen /= g;
+
+                sarArg = $"-vf \"{rotation},setsar={sarNum}:{sarDen}\" ";
+                darArg = $"-aspect {darNum}:{darDen} ";
+            }
+            else
+                sarArg = $"-vf \"{rotation}\" ";
+
             args =
                 $"-ss {start.ToString(CultureInfo.InvariantCulture)} " +
                 $"-i \"{inputFile}\" " +
                 $"-t {length.ToString(CultureInfo.InvariantCulture)} " +
-                $"-vf \"{rotation}\" " +
+                sarArg + darArg +
                 "-c:v h264_nvenc -preset p4 -b:v 8M -pix_fmt yuv420p " +
                 "-c:a copy " +
-                $"{pass} \"{outputFile}\" -y";
+                $"{string.Join(" ", job.Job.Passthrough)} " +
+                $"\"{outputFile}\" -y";
         }
-
         var psi = new ProcessStartInfo
         {
-            FileName = "ffmpeg",
+            FileName              = "ffmpeg",
-            Arguments = args,
+            Arguments             = args,
             RedirectStandardError = true,
-            UseShellExecute = false,
+            UseShellExecute       = false,
-            CreateNoWindow = true
+            CreateNoWindow        = true
         };
 
         using var proc = Process.Start(psi) ?? throw new Exception("Failed to start ffmpeg.");
 
         var name = Path.GetFileNameWithoutExtension(outputFile);
-        ShowFFMpegProgress(length, proc, name);
+        await ShowFFMpegProgress(length, proc, name, token);
 
-        proc.WaitForExit();
+        await proc.WaitForExitAsync(token);
-        
+
-        ClearProgress();
+        ClearProgress(name);
 
         if (proc.ExitCode != 0)
             LogError($"Segment {name} FFmpeg encoding failed");
@@ -65,6 +102,7 @@ public class SimpleSplitter(int segmentNo, ILogger logger) : LoggingBase(logger,
             LogInfo($"Segment {name} processing completed");
     }
 
+
     string? GetRotationFilter(int? degrees) =>
         degrees switch
         {
@@ -74,13 +112,27 @@ public class SimpleSplitter(int segmentNo, ILogger logger) : LoggingBase(logger,
             _ => null
         };
 
+    private static long Gcd(long a, long b)
+    {
+        a = Math.Abs(a);
+        b = Math.Abs(b);
 
-    private void ShowFFMpegProgress(double length, Process proc, string name)
+        while (b != 0)
+        {
+            long t = b;
+            b = a % b;
+            a = t;
+        }
+
+        return a;
+    }
+
+    private async Task ShowFFMpegProgress(double length, Process proc, string name, CancellationToken token)
     {
         var sw = Stopwatch.StartNew();
 
         string? line;
-        while ((line = proc.StandardError.ReadLine()) != null)
+        while ((line = await proc.StandardError.ReadLineAsync(token)) != null)
         {
             // Look for "time=00:00:03.52"
             var idx = line.IndexOf("time=", StringComparison.OrdinalIgnoreCase);

splitter-cli/SingleJob.cs

@@ -0,0 +1,118 @@
+using System.Globalization;
+
+namespace splitter;
+
+public class SingleJob
+{
+    /// <summary>
+    /// File path of the input video. This is required for each job and should be
+    /// set to a valid video file path. The splitter will read this file, analyze it, 
+    /// and split it into segments based on the specified parameters. 
+    /// The output segments will be saved in the OutputFolder with names 
+    /// derived from this input file and the Mask pattern if provided.
+    /// </summary>
+    public string                     InputFile              { get; set; } = null!;
+    /// <summary>
+    /// Output folder where the split segments will be saved. This should be set 
+    /// to a valid directory path.
+    /// </summary>
+    public string                     OutputFolder           { get; set; } = null!;
+    /// <summary>
+    /// Crop parameters. Width and height for cropping the video. If set, the 
+    /// splitter will crop the video to the specified dimensions while tracking the subject.
+    /// </summary>
+    public (int width, int height)?   Crop                   { get; set; }
+    /// <summary>
+    /// The fallback point to gravitate towards when tracking the subject. Coordinates are normalized (0.0 to 1.0).
+    /// By default , the splitter gravitates towards the center of the frame (0.5, 0.5). 
+    /// Setting this allows you to bias the tracking towards a specific area of the frame, 
+    /// such as left-center (0.2, 0.5) or top-right (0.8, 0.2). This can be useful for 
+    /// videos where the subject tends to be off-center or for creative framing choices.
+    /// </summary>
+    public Point2f?                   GravitateTo            { get; set; }
+    /// <summary>
+    /// Destination file mask.
+    /// </summary>
+    public string?                    Mask                   { get; set; }
+    /// <summary>
+    /// Instead of producing the output, just generate debug frames with tracking 
+    /// overlay to visually verify that the tracking is working correctly.
+    /// </summary>
+    public bool                       Debug                  { get; set; }
+    /// <summary>
+    /// Type of detector to use for tracking. Supported values are: face (UltraFace), 
+    /// body (YoloOnnx, default), none (no tracking, just a center point).
+    /// </summary>
+    public string?                    Detect                 { get; set; }
+    /// <summary>
+    /// Set starget segments length explicitly. By default, the splitter calculates segment 
+    /// lengths to be equal and not exceed 58 seconds.
+    /// </summary>
+    public double?                    OverrideTargetDuration { get; set; }
+    /// <summary>
+    /// Parameters to pass thru to ffmpeg. These are specified after "--" in the command 
+    /// line and are passed directly to the ffmpeg command line for each segment.
+    /// </summary>
+    public string[]                   Passthrough            { get; set; } = [];
+    /// <summary>
+    /// Debugging parameter. Instead of text UI putput lines in plain text. 
+    /// This is useful when the output is being piped to a file or another program, 
+    /// or when the user prefers a simpler log format without progress bars and dynamic updates.
+    /// </summary>
+    public bool                       PlainText              { get; set; }
+    /// <summary>
+    /// Debugging parameter. Just show estimated segments length, count, and other info 
+    /// without actually performing the splitting.
+    /// </summary>
+    public bool                       EstimateOnly           { get; set; }
+    /// <summary>
+    /// Do not adapt segment length. When set, the splitter will use the exact 
+    /// segment duration specified by --duration for all segments except possibly 
+    /// the last one, which may be shorter.
+    /// </summary>
+    public bool                       ForceFixed             { get; set; }
+    /// <summary>
+    /// Use single thread for operations. When set, the splitter will not run 
+    /// multiple ffmpeg processes in parallel.
+    /// </summary>
+    public bool                       SingleThreaded         { get; set; }
+    /// <summary>
+    /// Rotation angle: 90, 180, or 270 degrees. This is useful for videos that 
+    /// have incorrect orientation metadata.
+    /// </summary>
+    public int?                       Rotate                 { get; set; }
+    /// <summary>
+    /// Autodetect if rotation is needed. Not very reliable but can work for some videos. 
+    /// Uses edge orientation statistics to determine if the video is rotated and 
+    /// applies the appropriate rotation if needed.
+    /// </summary>
+    public bool                       RotateAuto             { get; set; }
+    /// <summary>
+    /// Override internal parameters. This allows you to set custom parameters for the 
+    /// object detector or rotation detector.
+    /// </summary>
+    public Dictionary<string, string> Parameters             { get; set; } = [];
+
+    public void Override<T>(ref T member, string name)
+    {
+        if (!Parameters.TryGetValue(name, out var raw))
+            return;
+
+        try
+        {
+            // Convert.ChangeType handles int, float, double, etc.
+            var converted = (T)Convert.ChangeType(
+            raw,
+            typeof(T),
+            CultureInfo.InvariantCulture
+        );
+
+            member = converted;
+        }
+        catch
+        {
+            Console.WriteLine($"Invalid value for parameter '{name}': {raw}");
+        }
+    }
+
+}

splitter-cli/TrackingSplitter.cs

@@ -1,7 +1,6 @@
 using System.Diagnostics;
 using System.Globalization;
 using System.Runtime.InteropServices;
-using OpenCvSharp;
 
 namespace splitter;
 
@@ -25,7 +24,7 @@ public class TrackingSplitter : LoggingBase, ISegmentProcessor, IDisposable
             d.Dispose();
     }
 
-    public async Task ProcessSegment(SingleTask job)
+    public async Task ProcessSegment(SingleTask job, CancellationToken token)
     {
         string inputFile                     = job.Job.InputFile;
         string outputFile                    = job.OutputFileName;
@@ -58,20 +57,21 @@ public class TrackingSplitter : LoggingBase, ISegmentProcessor, IDisposable
         LogInfo($"{name}: src={videoWidth}x{videoHeight} @ {fps:F3}fps, seg=[{start:F3},{length:F3}] enc={encWidth}x{encHeight}");
 
         // 2) Start FFmpeg decode (video only → raw BGR24 to stdout)
-        var decode = StartFfmpegDecode(inputFile, start, length, job.Job.Rotate, job.Job.PlainText);
+        var decode = await StartFfmpegDecode(inputFile, start, length, job.Job.Rotate, job.Job.PlainText, token);
         using var decodeStdout = decode.StandardOutput.BaseStream;
 
         // 3) Start FFmpeg encode (video from stdin + audio from original)
-        var encode = StartFfmpegEncode(
+        var encode = await StartFfmpegEncode(
             inputFile,
             outputFile,
             start,
             length,
             encWidth,
             encHeight,
-            fps,
+            job.Info,
             ffmpegPassthroughParameters,
-            job.Job.PlainText);
+            job.Job.PlainText,
+            token);
 
         using var encodeStdin = encode.StandardInput.BaseStream;
 
@@ -100,9 +100,11 @@ public class TrackingSplitter : LoggingBase, ISegmentProcessor, IDisposable
 
         while (frameIndex < totalFrames)
         {
+            token.ThrowIfCancellationRequested();
+
             frameIndex++;
 
-            var read = ReadExact(decodeStdout, inBuffer, 0, inBytes);
+            var read = await ReadExact(decodeStdout, inBuffer, 0, inBytes, token);
             if (read != inBytes)
                 break;
 
@@ -153,7 +155,7 @@ public class TrackingSplitter : LoggingBase, ISegmentProcessor, IDisposable
         try { if (!decode.HasExited) decode.Kill(entireProcessTree: true); } catch { }
         try { if (!decode.HasExited) await decode.WaitForExitAsync(); } catch { }
 
-        ClearProgress();
+        ClearProgress(name);
 
 
         if (encode.ExitCode != 0)
@@ -165,21 +167,12 @@ public class TrackingSplitter : LoggingBase, ISegmentProcessor, IDisposable
 
     // ---------- FFmpeg decode / encode ----------
 
-    private Process StartFfmpegDecode(string inputFile, double start, double length, int? rotate, bool plainText)
+    private async Task<Process> StartFfmpegDecode(string inputFile, double start, double length, int? rotate, bool plainText, CancellationToken token)
     {
         var ss = start .ToString("0.###", CultureInfo.InvariantCulture);
         var t  = length.ToString("0.###", CultureInfo.InvariantCulture);
 
-        var rotateStr = "";
+        var rotateStr = GetRorationArg(rotate);
-        if (rotate != null)
-        {
-            switch (rotate.Value)
-            {
-                case 90:  rotateStr = ",transpose=1";  break;
-                case 180: rotateStr = ",transpose=PI"; break;
-                case 270: rotateStr = ",transpose=2";  break;
-            }
-        }
 
         var args =
     $"-i \"{inputFile}\" -ss {ss} -t {t} " +
@@ -202,12 +195,12 @@ public class TrackingSplitter : LoggingBase, ISegmentProcessor, IDisposable
 
         var fileName = Path.GetFileName(inputFile);
 
-        _ = Task.Run(() =>
+        _ = Task.Run(async () =>
         {
             try
             {
                 string? line;
-                while ((line = p.StandardError.ReadLine()) != null)
+                while ((line = await p.StandardError.ReadLineAsync(token)) != null)
                     if (plainText)
                         LogInfo($"[ffmpeg-decode] {fileName}: {line}");
             }
@@ -217,21 +210,57 @@ public class TrackingSplitter : LoggingBase, ISegmentProcessor, IDisposable
         return p;
     }
 
-    private Process StartFfmpegEncode(
+    public static string GetRorationArg(int? rotate)
+    {
+        var rotateStr = "";
+        if (rotate != null)
+        {
+            switch (rotate.Value)
+            {
+                case 90: rotateStr = ",transpose=1"; break;
+                case 180: rotateStr = ",transpose=PI"; break;
+                case 270: rotateStr = ",transpose=2"; break;
+            }
+        }
+
+        return rotateStr;
+    }
+
+    private async Task<Process> StartFfmpegEncode(
         string inputFile,
         string outputFile,
         double start,
         double length,
-        int width,
+        int width, int height,
-        int height,
+        VideoInfo info,
-        double fps,
         string[] passthrough,
-        bool plainText)
+        bool plainText,
+        CancellationToken token)
     {
         var pass   = passthrough.Length > 0 ? string.Join(" ", passthrough) : "";
-        var fpsStr = fps.ToString("0.###", CultureInfo.InvariantCulture);
+        var fpsStr = info.Fps.ToString("0.###", CultureInfo.InvariantCulture);
         var ss     = start.ToString("0.###", CultureInfo.InvariantCulture);
         var t      = length.ToString("0.###", CultureInfo.InvariantCulture);
+        var sarArg = !string.IsNullOrWhiteSpace(info.SampleAspectRatio)
+            ? $"-vf setsar={info.SampleAspectRatio} "
+            : "";
+
+        string darArg    = "";
+
+        if (info.Sar is { } s)
+        {
+            // compute DAR from output size and SAR
+            var darNum = width * s.X;
+            var darDen = height * s.Y;
+
+            // clamp to int and reduce
+            int dn = (int)Math.Min(int.MaxValue, Math.Max(int.MinValue, darNum));
+            int dd = (int)Math.Min(int.MaxValue, Math.Max(int.MinValue, darDen));
+            ReduceFraction(ref dn, ref dd);
+
+            if (dn > 0 && dd > 0)
+                darArg = $"-aspect {dn}:{dd} ";
+        }
 
         var args =
             "-y " +
@@ -239,6 +268,7 @@ public class TrackingSplitter : LoggingBase, ISegmentProcessor, IDisposable
             $"-ss {ss} -i \"{inputFile}\" " +
             "-map 0:v:0 -map 1:a:0? -shortest " +
             "-c:v h264_nvenc -preset p4 -b:v 8M -pix_fmt yuv420p " +
+            sarArg + darArg +
             "-c:a copy " +
             pass + $" \"{outputFile}\"";
 
@@ -260,12 +290,12 @@ public class TrackingSplitter : LoggingBase, ISegmentProcessor, IDisposable
 
         var fileName = Path.GetFileName(outputFile);
 
-        _ = Task.Run(() =>
+        _ = Task.Run(async () =>
         {
             try
             {
                 string? line;
-                while ((line = p.StandardError.ReadLine()) != null)
+                while ((line = await p.StandardError.ReadLineAsync(token)) != null)
                 {
                     if (plainText)
                         LogInfo($"[ffmpeg-encode] {fileName}: {line}");
@@ -279,12 +309,32 @@ public class TrackingSplitter : LoggingBase, ISegmentProcessor, IDisposable
 
     // ---------- helpers ----------
 
-    private static int ReadExact(Stream s, byte[] buffer, int offset, int count)
+    private static void ReduceFraction(ref int num, ref int den)
+    {
+        int Gcd(int a, int b)
+        {
+            while (b != 0)
+            {
+                var t = b;
+                b = a % b;
+                a = t;
+            }
+            return a;
+        }
+
+        var g = Gcd(Math.Abs(num), Math.Abs(den));
+        if (g > 1)
+        {
+            num /= g;
+            den /= g;
+        }
+    }
+    private static async Task<int> ReadExact(Stream s, byte[] buffer, int offset, int count, CancellationToken token)
     {
         var total = 0;
         while (total < count)
         {
-            var read = s.Read(buffer, offset + total, count - total);
+            var read = await s.ReadAsync(buffer, offset + total, count - total, token);
             if (read <= 0)
                 break;
             total += read;

splitter-cli/algo/CameraController.cs

@@ -1,6 +1,4 @@
-using OpenCvSharp;
+namespace splitter.algo;
-
-namespace splitter;
 
 public enum TrackState
 {

splitter-cli/algo/IObjectDetector.cs

@@ -1,6 +1,4 @@
-using OpenCvSharp;
+namespace splitter.algo;
-
-namespace splitter;
 
 public interface IObjectDetector : IDisposable
 {

splitter-cli/algo/ISegmentProcessor.cs

@@ -0,0 +1,6 @@
+namespace splitter.algo;
+
+public interface ISegmentProcessor
+{
+    Task ProcessSegment( SingleTask job, CancellationToken token);
+}

splitter-cli/algo/KalmanTracker.cs

@@ -1,4 +1,4 @@
-namespace splitter;
+namespace splitter.algo;
 
 public sealed class KalmanTracker
 {

splitter-cli/algo/Point2f.cs

@@ -0,0 +1,13 @@
+//namespace splitter.algo;
+
+//public struct Point2f
+//{
+//    public float X;
+//    public float Y;
+
+//    public Point2f(float x, float y)
+//    {
+//        X = x;
+//        Y = y;
+//    }
+//}

splitter-cli/algo/UltraFaceDetector.cs

@@ -1,8 +1,7 @@
 using System.Runtime.InteropServices;
-using OpenCvSharp;
 using UltraFaceDotNet;
 
-namespace splitter;
+namespace splitter.algo;
 
 public sealed class UltraFaceDetector: LoggingBase, IDisposable, IObjectDetector
 {

splitter-cli/algo/YoloOnnxObjectDetector.cs

@@ -1,9 +1,8 @@
 using System.Runtime.CompilerServices;
 using Microsoft.ML.OnnxRuntime;
 using Microsoft.ML.OnnxRuntime.Tensors;
-using OpenCvSharp;
 
-namespace splitter;
+namespace splitter.algo;
 
 public sealed class YoloOnnxObjectDetector : LoggingBase, IObjectDetector, IDisposable
 {

splitter-cli/probe/FfprobeFormat.cs

@@ -0,0 +1,37 @@
+using System.Text.Json.Serialization;
+
+namespace splitter.probe;
+
+public sealed class FfprobeFormat
+{
+    public string? Filename                 { get; set; }
+
+    [JsonConverter(typeof(FlexibleIntConverter))]
+    public int? Nb_streams                  { get; set; }
+
+    [JsonConverter(typeof(FlexibleIntConverter))]
+    public int? Nb_programs                 { get; set; }
+
+    [JsonConverter(typeof(FlexibleIntConverter))]
+    public int? Nb_stream_groups            { get; set; }
+
+    public string? Format_name              { get; set; }
+    public string? Format_long_name         { get; set; }
+
+    [JsonConverter(typeof(FlexibleDoubleConverter))]
+    public double? Start_time               { get; set; }
+
+    [JsonConverter(typeof(FlexibleDoubleConverter))]
+    public double? Duration                 { get; set; }
+
+    [JsonConverter(typeof(FlexibleLongConverter))]
+    public long? Size                       { get; set; }
+
+    [JsonConverter(typeof(FlexibleLongConverter))]
+    public long? Bit_rate                   { get; set; }
+
+    [JsonConverter(typeof(FlexibleIntConverter))]
+    public int? Probe_score                 { get; set; }
+
+    public Dictionary<string, string>? Tags { get; set; }
+}

splitter-cli/probe/FfprobeResult.cs

@@ -0,0 +1,7 @@
+namespace splitter.probe;
+
+public sealed class FfprobeResult
+{
+    public List<FfprobeStream>? Streams { get; set; }
+    public FfprobeFormat? Format { get; set; }
+}

splitter-cli/probe/FfprobeStream.cs

@@ -0,0 +1,126 @@
+using System.Text.Json.Serialization;
+
+namespace splitter.probe;
+
+public sealed class FfprobeStream
+{
+    [JsonConverter(typeof(FlexibleIntConverter))]
+    public int? Index                           { get; set; }
+
+    public string? Codec_name                   { get; set; }
+    public string? Codec_long_name              { get; set; }
+    public string? Profile                      { get; set; }
+    public string? Codec_type                   { get; set; }
+    public string? Codec_tag_string             { get; set; }
+    public string? Codec_tag                    { get; set; }
+    public string? Mime_codec_string            { get; set; }
+
+    [JsonConverter(typeof(FlexibleIntConverter))]
+    public int? Width                           { get; set; }
+
+    [JsonConverter(typeof(FlexibleIntConverter))]
+    public int? Height                          { get; set; }
+
+    [JsonConverter(typeof(FlexibleIntConverter))]
+    public int? Coded_width                     { get; set; }
+
+    [JsonConverter(typeof(FlexibleIntConverter))]
+    public int? Coded_height                    { get; set; }
+
+    [JsonConverter(typeof(FlexibleIntConverter))]
+    public int? Closed_captions                 { get; set; }
+
+    [JsonConverter(typeof(FlexibleIntConverter))]
+    public int? Film_grain                      { get; set; }
+
+    [JsonConverter(typeof(FlexibleIntConverter))]
+    public int? Has_b_frames                    { get; set; }
+
+    public string? Sample_aspect_ratio          { get; set; }
+    public string? Display_aspect_ratio         { get; set; }
+
+    public string? Pix_fmt                      { get; set; }
+
+    [JsonConverter(typeof(FlexibleIntConverter))]
+    public int? Level                           { get; set; }
+
+    public string? Color_range                  { get; set; }
+    public string? Color_space                  { get; set; }
+    public string? Color_transfer               { get; set; }
+    public string? Color_primaries              { get; set; }
+    public string? Chroma_location              { get; set; }
+    public string? Field_order                  { get; set; }
+
+    public string? Is_avc                       { get; set; }
+    public string? Nal_length_size              { get; set; }
+
+    public string? Id                           { get; set; }
+    public string? R_frame_rate                 { get; set; }
+    public string? Avg_frame_rate               { get; set; }
+    public string? Time_base                    { get; set; }
+
+    [JsonConverter(typeof(FlexibleLongConverter))]
+    public long? Start_pts                      { get; set; }
+
+    [JsonConverter(typeof(FlexibleDoubleConverter))]
+    public double? Start_time                   { get; set; }
+
+    [JsonConverter(typeof(FlexibleLongConverter))]
+    public long? Duration_ts                    { get; set; }
+
+    [JsonConverter(typeof(FlexibleDoubleConverter))]
+    public double? Duration                     { get; set; }
+
+    [JsonConverter(typeof(FlexibleLongConverter))]
+    public long? Bit_rate                       { get; set; }
+
+    [JsonConverter(typeof(FlexibleLongConverter))]
+    public long? Max_bit_rate                   { get; set; }
+
+    [JsonConverter(typeof(FlexibleIntConverter))]
+    public int? Bits_per_raw_sample             { get; set; }
+
+    [JsonConverter(typeof(FlexibleIntConverter))]
+    public int? Bits_per_sample                 { get; set; }
+
+    [JsonConverter(typeof(FlexibleLongConverter))]
+    public long? Nb_frames                      { get; set; }
+
+    [JsonConverter(typeof(FlexibleIntConverter))]
+    public int? Extradata_size                  { get; set; }
+
+    [JsonConverter(typeof(FlexibleIntConverter))]
+    public int? Channels                        { get; set; }
+
+    public string? Channel_layout               { get; set; }
+    public string? Sample_fmt                   { get; set; }
+
+    [JsonConverter(typeof(FlexibleIntConverter))]
+    public int? Sample_rate                     { get; set; }
+
+    [JsonConverter(typeof(FlexibleIntConverter))]
+    public int? Initial_padding                 { get; set; }
+
+    public string? Disposition_raw              { get; set; }
+    public Dictionary<string, int>? Disposition { get; set; }
+
+    public Dictionary<string, string>? Tags     { get; set; }
+
+    public string? Language                     { get; set; }
+    public string? Title                        { get; set; }
+
+    [JsonConverter(typeof(FlexibleIntConverter))]
+    public int? Bits_per_coded_sample           { get; set; }
+
+    public string? Codec_time_base              { get; set; }
+
+    [JsonConverter(typeof(FlexibleDoubleConverter))]
+    public double? Start_pts_time               { get; set; }
+
+    [JsonConverter(typeof(FlexibleDoubleConverter))]
+    public double? Duration_time                { get; set; }
+
+    public string? Extradata                    { get; set; }
+    public string? Default                      { get; set; }
+    public string? Forced                       { get; set; }
+}

splitter-cli/probe/FlexibleDoubleConverter.cs

@@ -0,0 +1,31 @@
+using System.Globalization;
+using System.Text.Json;
+using System.Text.Json.Serialization;
+
+namespace splitter.probe;
+
+public sealed class FlexibleDoubleConverter : JsonConverter<double?>
+{
+    public override double? Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options)
+    {
+        if (reader.TokenType == JsonTokenType.Number)
+            return reader.GetDouble();
+
+        if (reader.TokenType == JsonTokenType.String)
+        {
+            var s = reader.GetString();
+            if (double.TryParse(s, NumberStyles.Float, CultureInfo.InvariantCulture, out var v))
+                return v;
+        }
+
+        return null;
+    }
+
+    public override void Write(Utf8JsonWriter writer, double? value, JsonSerializerOptions options)
+    {
+        if (value.HasValue)
+            writer.WriteNumberValue(value.Value);
+        else
+            writer.WriteNullValue();
+    }
+}

splitter-cli/probe/FlexibleIntConverter.cs

@@ -0,0 +1,31 @@
+using System.Globalization;
+using System.Text.Json;
+using System.Text.Json.Serialization;
+
+namespace splitter.probe;
+
+public sealed class FlexibleIntConverter : JsonConverter<int?>
+{
+    public override int? Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options)
+    {
+        if (reader.TokenType == JsonTokenType.Number)
+            return reader.GetInt32();
+
+        if (reader.TokenType == JsonTokenType.String)
+        {
+            var s = reader.GetString();
+            if (int.TryParse(s, NumberStyles.Integer, CultureInfo.InvariantCulture, out var v))
+                return v;
+        }
+
+        return null;
+    }
+
+    public override void Write(Utf8JsonWriter writer, int? value, JsonSerializerOptions options)
+    {
+        if (value.HasValue)
+            writer.WriteNumberValue(value.Value);
+        else
+            writer.WriteNullValue();
+    }
+}

splitter-cli/probe/FlexibleLongConverter.cs

@@ -0,0 +1,31 @@
+using System.Globalization;
+using System.Text.Json;
+using System.Text.Json.Serialization;
+
+namespace splitter.probe;
+
+public sealed class FlexibleLongConverter : JsonConverter<long?>
+{
+    public override long? Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options)
+    {
+        if (reader.TokenType == JsonTokenType.Number)
+            return reader.GetInt64();
+
+        if (reader.TokenType == JsonTokenType.String)
+        {
+            var s = reader.GetString();
+            if (long.TryParse(s, NumberStyles.Integer, CultureInfo.InvariantCulture, out var v))
+                return v;
+        }
+
+        return null;
+    }
+
+    public override void Write(Utf8JsonWriter writer, long? value, JsonSerializerOptions options)
+    {
+        if (value.HasValue)
+            writer.WriteNumberValue(value.Value);
+        else
+            writer.WriteNullValue();
+    }
+}

splitter-cli/probe/FrameRotationDetector.cs

@@ -1,6 +1,4 @@
-using OpenCvSharp;
+namespace splitter.probe;
-
-namespace splitter;
 
 public sealed class FrameRotationDetector
 {
@@ -18,17 +16,17 @@ public sealed class FrameRotationDetector
 
     public FrameRotationDetector(int width = 320, int height = 180, int bins = 36)
     {
-        _w = width;
+        _w     = width;
-        _h = height;
+        _h     = height;
-        _bins = bins;
+        _bins  = bins;
 
-        _gray = new Mat(height, width, MatType.CV_8UC1);
+        _gray  = new Mat(height, width, MatType.CV_8UC1);
-        _gx = new Mat(height, width, MatType.CV_32F);
+        _gx    = new Mat(height, width, MatType.CV_32F);
-        _gy = new Mat(height, width, MatType.CV_32F);
+        _gy    = new Mat(height, width, MatType.CV_32F);
-        _mag = new Mat(height, width, MatType.CV_32F);
+        _mag   = new Mat(height, width, MatType.CV_32F);
         _angle = new Mat(height, width, MatType.CV_32F);
 
-        _hist = new float[bins];   // allocated once
+        _hist  = new float[bins];   // allocated once
     }
 
     public int GetRotation(Mat frame)

splitter-cli/probe/ProbeVideo.cs

@@ -0,0 +1,93 @@
+using System.Diagnostics;
+using System.Globalization;
+using System.Text.Json;
+using System.Text.Json.Serialization;
+
+namespace splitter.probe;
+
+public static class ProbeVideo
+{
+    static ProbeVideo()
+    {
+        _ffprobeJsonOptions.Converters.Add(new FlexibleDoubleConverter());
+        _ffprobeJsonOptions.Converters.Add(new FlexibleIntConverter());
+        _ffprobeJsonOptions.Converters.Add(new FlexibleLongConverter());
+    }
+
+    public static async Task<VideoInfo> Probe(string inputFile, bool detectRotation, CancellationToken token)
+    {
+        var info = await ProbeSize(inputFile, token);
+        if (detectRotation)
+        {
+            var rotation = await ProbeRotation(inputFile, info.Duration, token);
+            info = info with { Rotation = rotation };
+        }
+
+        return info;
+    }
+
+    private static async Task<int> ProbeRotation(string inputFile, double duration, CancellationToken token)
+        => await new VideoRotationSampler(null).DetectRotationAsync(inputFile, duration, token);
+
+    private static readonly JsonSerializerOptions _ffprobeJsonOptions =
+        new ()
+        {
+            PropertyNameCaseInsensitive = true,
+            IgnoreReadOnlyProperties    = false,
+            AllowTrailingCommas         = true,
+            ReadCommentHandling         = JsonCommentHandling.Skip,
+            UnknownTypeHandling         = JsonUnknownTypeHandling.JsonElement
+        };
+
+    private static async Task<VideoInfo> ProbeSize(string inputFile, CancellationToken token)
+    {
+        var args =
+            "-v error " +
+            "-show_streams " +
+            "-show_format " +
+            "-of json " +
+            $"\"{inputFile}\"";
+
+        var psi = new ProcessStartInfo
+        {
+            FileName               = "ffprobe",
+            Arguments              = args,
+            RedirectStandardOutput = true,
+            RedirectStandardError  = true,
+            UseShellExecute        = false,
+            CreateNoWindow         = true
+        };
+
+        using var p = new Process { StartInfo = psi };
+        p.Start();
+
+        var json = await p.StandardOutput.ReadToEndAsync(token);
+        await p.WaitForExitAsync(token);
+
+        var result = JsonSerializer.Deserialize<FfprobeResult>(json, _ffprobeJsonOptions);
+        var stream = result?.Streams?.FirstOrDefault();
+        var format = result?.Format;
+
+        var duration = format?.Duration ?? 0.0;
+        var width    = stream?.Width ?? 0;
+        var height   = stream?.Height ?? 0;
+
+        double fps = 0.0;
+        if (!string.IsNullOrWhiteSpace(stream?.Avg_frame_rate))
+        {
+            var parts = stream.Avg_frame_rate.Split('/');
+            if (parts.Length == 2 &&
+                double.TryParse(parts[0], NumberStyles.Float, CultureInfo.InvariantCulture, out var num) &&
+                double.TryParse(parts[1], NumberStyles.Float, CultureInfo.InvariantCulture, out var den) &&
+                den != 0)
+            {
+                fps = num / den;
+            }
+        }
+
+        var bitrate = stream?.Bit_rate ?? 0.0;
+
+        return new VideoInfo(duration, width, height, fps, bitrate, stream?.Sample_aspect_ratio, stream?.Display_aspect_ratio);
+    }
+
+}

splitter-cli/probe/VideoInfo.cs

@@ -0,0 +1,37 @@
+using System.Globalization;
+
+namespace splitter.probe;
+
+public record VideoInfo(
+    double Duration,
+    int Width,
+    int Height,
+    double Fps,
+    double Bitrate,
+    string? SampleAspectRatio,
+    string? DisplayAspectRatio,
+    int Rotation = 0
+)
+{
+    public Point2f Sar => ParseAspectRatio(SampleAspectRatio);
+    public Point2f Dar => ParseAspectRatio(DisplayAspectRatio);
+
+    private static Point2f ParseAspectRatio(string? sar)
+    {
+        if (string.IsNullOrWhiteSpace(sar))
+            return new Point2f(1.0f, 1.0f);
+
+        var parts = sar.Split(':');
+        if (parts.Length != 2)
+            return new(1.0f, 1.0f);
+
+        if (float.TryParse(parts[0], NumberStyles.Float, CultureInfo.InvariantCulture, out var num) &&
+            float.TryParse(parts[1], NumberStyles.Float, CultureInfo.InvariantCulture, out var den) &&
+            den != 0)
+        {
+            return new(num, den);
+        }
+
+        return new(1.0f, 1.0f);
+    }
+}

splitter-cli/probe/VideoRotationSampler.cs

@@ -1,13 +1,12 @@
-using OpenCvSharp;
+using System.Diagnostics;
-using System.Diagnostics;
 
-namespace splitter;
+namespace splitter.probe;
 
 public sealed class VideoRotationSampler
 {
     private readonly FrameRotationDetector _detector = new FrameRotationDetector();
 
-    public static int    RotationDetectorSampleCount  = 20;
+    public static int    RotationDetectorSampleCount  = 10;
     public static double RotationDetectorSampleLength = 0.15;  // seconds to decode per probe
     public static int    RotationDetectorFrameWidth   = 320;
     public static int    RotationDetectorFrameHeight  = 180;
@@ -16,16 +15,19 @@ public sealed class VideoRotationSampler
     private readonly byte[] _buffer;
     private readonly Mat _frameMat;
 
-    public VideoRotationSampler(SingleJob _master)
+    public VideoRotationSampler(IDictionary<string, string>? overrides)
     {
-        if (_master.Parameters.TryGetValue("RotationDetectorSampleCount", out var s))
+        if (overrides != null)
-            RotationDetectorSampleCount  = int.Parse(s);
+        {
-        if (_master.Parameters.TryGetValue("RotationDetectorSampleLength", out s))
+            if (overrides.TryGetValue("RotationDetectorSampleCount", out var s))
-            RotationDetectorSampleLength = double.Parse(s);
+                RotationDetectorSampleCount = int.Parse(s);
-        if (_master.Parameters.TryGetValue("RotationDetectorFrameWidth", out s))
+            if (overrides.TryGetValue("RotationDetectorSampleLength", out s))
-            RotationDetectorFrameWidth   = int.Parse(s);
+                RotationDetectorSampleLength = double.Parse(s);
-        if (_master.Parameters.TryGetValue("RotationDetectorFrameHeight", out s))
+            if (overrides.TryGetValue("RotationDetectorFrameWidth", out s))
-            RotationDetectorFrameHeight  = int.Parse(s);
+                RotationDetectorFrameWidth = int.Parse(s);
+            if (overrides.TryGetValue("RotationDetectorFrameHeight", out s))
+                RotationDetectorFrameHeight = int.Parse(s);
+        }
 
         int w = RotationDetectorFrameWidth;
         int h = RotationDetectorFrameHeight;
@@ -36,7 +38,8 @@ public sealed class VideoRotationSampler
 
     public async Task<int> DetectRotationAsync(
          string inputFile,
-         double videoLengthSeconds)
+         double videoLengthSeconds,
+         CancellationToken token)
     {
         if (videoLengthSeconds <= 0)
             return 0;
@@ -52,7 +55,8 @@ public sealed class VideoRotationSampler
                 t,
                 RotationDetectorSampleLength,
                 RotationDetectorFrameWidth,
-                RotationDetectorFrameHeight);
+                RotationDetectorFrameHeight,
+                token);
 
             if (frame != null && !frame.Empty())
             {
@@ -96,18 +100,21 @@ public sealed class VideoRotationSampler
         double start,
         double length,
         int width,
-        int height)
+        int height,
+        CancellationToken token)
     {
         var p = StartFfmpegDecode(inputFile, start, length, rotate: null, plainText: false);
 
-        int needed = _buffer.Length;
+        var needed = _buffer.Length;
-        int read = 0;
+        var read = 0;
 
         using var stdout = p.StandardOutput.BaseStream;
 
         while (read < needed)
         {
-            int r = await stdout.ReadAsync(_buffer, read, needed - read);
+            token.ThrowIfCancellationRequested();
+
+            var r = await stdout.ReadAsync(_buffer, read, needed - read, token);
             if (r == 0)
                 return null;
             read += r;

splitter-cli/splitter.cs

@@ -1,6 +1,3 @@
-using System.Collections.Concurrent;
-using System.Diagnostics;
-using Spectre.Console;
 using splitter;
 
 static partial class Program
@@ -33,24 +30,26 @@ static partial class Program
             uiTask = logger.RunAsync(cts.Token);
         }
 
+        var processor = new JobProcessor(_logger);
+
         if (cmd.Master.EstimateOnly)
-            LogInfo("=== ESTIMATE MODE ===");
+            _logger.LogInfo("=== ESTIMATE MODE ===");
 
         var allJobs = new List<SingleTask>();
         foreach ( var job in cmd.Jobs )
         {
-            var jobs = await GenerateJobs(cmd, job);
+            var jobs = await processor.GenerateJobs(job, cmd.Master.EstimateOnly, CancellationToken.None);
             allJobs.AddRange(jobs);
         }
 
         if ( allJobs.Count == 0)
         {
             if ( !cmd.Master.EstimateOnly)
-                LogWarn("No valid jobs to process.");
+                _logger.LogWarn("No valid jobs to process.");
             return 0;
         }
 
-        var success = await ProcessJobs(cmd, allJobs);
+        var success = await processor.ProcessJobs(allJobs, cmd.Master.SingleThreaded, CancellationToken.None);
         if (uiTask != null)
         {
             if ( cts != null )
@@ -63,217 +62,4 @@ static partial class Program
         return success ? 1 : 0;
     }
 
-    private static async Task<List<SingleTask>> GenerateJobs(CommandLine cmd, SingleJob job)
-    {
-        var baseName = Path.GetFileNameWithoutExtension(job.InputFile);
-
-        if (!File.Exists(job.InputFile))
-        {
-            LogError($"{baseName}: Input file not found.");
-            return [];
-        }
-
-        if (!Directory.Exists(job.OutputFolder))
-            Directory.CreateDirectory(job.OutputFolder);
-
-        var info = await ProbeVideo.Probe(job);
-        if (info.Duration <= 0)
-        {
-            LogError($"{baseName}: Could not read duration.");
-            return [];
-        }
-
-        var target = job.OverrideTargetDuration ?? 58.0;
-
-        int segments;
-        double segmentLength;
-
-        if (job.ForceFixed)
-        {
-            // Fixed chunk size, last one may be shorter
-            segments = (int)Math.Ceiling(info.Duration / target);
-            segmentLength = target;
-        }
-        else
-        {
-            // Equalized segments
-            segments = (int)Math.Ceiling(info.Duration / target);
-            segmentLength = info.Duration / segments;
-        }
-
-        LogInfo($"{baseName}: Duration {info.Duration:F2}s, {info.Width}x{info.Height} @ {info.Fps:F3}fps {info.Bitrate/1024:F0}kbps," +
-            $" Target duration: {target:F2}s Segments: {segments} segment length: {segmentLength:F2}s {(job.ForceFixed ? " fixed" : "")}" );
-
-        if (cmd.Master.EstimateOnly)
-            return [];
-
-        Func<int, ISegmentProcessor> processorFactory;
-        if (job.Crop != null)
-        {
-            processorFactory = i =>
-            {
-                IObjectDetector detector = job.Detect switch
-                {
-                    "face" => new UltraFaceDetector(_logger),
-                    "body" => new YoloOnnxObjectDetector(_logger),
-                    _      => throw new InvalidOperationException($"Unknown detector: {job.Detect}")
-                };
-                return new TrackingSplitter(i, detector, job, _logger);
-            };
-        }
-        else
-        {
-            processorFactory = i => new SimpleSplitter(i, _logger);
-        }
-
-        var jobs = Enumerable.Range(0, segments)
-            .Select(i => new SingleTask
-                (
-                    Job              : job,
-                    Info: info,
-                    OutputFileName   : BuildOutputFileName(job, i),
-                    SegmentIndex     : i,
-                    TotalSegments    : segments,
-                    SegmentStart     : i * segmentLength,
-                    SegmentLength    : (i == segments - 1)
-                        ? Math.Max(0.1, info.Duration - i * segmentLength)
-                                     : segmentLength,
-                    ProcessorFactory : processorFactory
-                )
-            )
-            .ToList();
-
-        return jobs;
-    }
-
-    private static async Task<bool> ProcessJobs(CommandLine cmd, List<SingleTask> tasks)
-    { 
-
-        if (cmd.Master.SingleThreaded)
-        {
-            LogInfo("Starting single-threaded splitting...");
-            await RunSingleThreaded(tasks);
-        }
-        else
-        {
-            LogInfo("Starting multi-threaded splitting...");
-            await RunMultiThreaded(tasks);
-        }
-
-        LogInfo("Done.");
-        return true;
-    }
-
-    private static void LogInfo(string message)  => _logger.LogInfo(message);
-    private static void LogWarn(string message)  => _logger.LogWarn(message);
-    private static void LogError(string message) => _logger.LogError(message);
-    private static void LogProgress(double progress, TimeSpan eta, double speed) => _logger.DrawProgress("Total", 0, progress, eta, speed);
-
-    // -----------------------------
-    // ffprobe
-    // -----------------------------
-
-    // -----------------------------
-    // Multi-threaded splitting
-    // -----------------------------
-
-    static async Task RunMultiThreaded(List<SingleTask> jobs)
-    {
-        LogProgress(0.0, TimeSpan.Zero, 0.0);
-
-        var maxDegree = Math.Max(1, Environment.ProcessorCount / 2);
-
-        using var sem = new SemaphoreSlim(maxDegree);
-        var tasks = new List<Task>();
-
-        // Slot pool: 0..maxDegree-1
-        var freeSlots = new ConcurrentQueue<int>(Enumerable.Range(0, maxDegree));
-
-        var totalSegments     = jobs.Count;
-        var processedSegments = 0;
-        var totalDuration     = jobs.Sum(j => j.SegmentLength);
-        var sw                = Stopwatch.StartNew();
-
-        foreach (var job in jobs)
-        {
-            await sem.WaitAsync();
-
-            tasks.Add(Task.Run(async () =>
-            {
-                int slot = -1;
-
-                try
-                {
-                    // Acquire a slot ID
-                    while (!freeSlots.TryDequeue(out slot))
-                        await Task.Yield();
-
-                    await ProcessSegment(job,slot + 1);
-
-                    var processed = Interlocked.Increment(ref processedSegments);
-                    var elapsed   = sw.Elapsed;
-                    var eta       = TimeSpan.FromTicks(elapsed.Ticks * (totalSegments - processed) / processed);
-                    var speed     = (processed * totalDuration) / elapsed.TotalSeconds;
-                    LogProgress((double)processed / totalSegments, eta, speed);
-                }
-                finally
-                {
-                    // Return slot to pool
-                    if (slot >= 0)
-                        freeSlots.Enqueue(slot);
-
-                    sem.Release();
-                }
-            }));
-        }
-
-        await Task.WhenAll(tasks);
-    }
-
-
-    // -----------------------------
-    // Single-threaded splitting
-    // -----------------------------
-
-    static async Task RunSingleThreaded(List<SingleTask> jobs)
-    {
-        foreach (var job in jobs)
-        {
-            await ProcessSegment(job, 0);
-        }
-
-    }
-
-    private static async Task ProcessSegment(SingleTask t, int slot)
-    {
-        var processor = t.ProcessorFactory(slot);
-        try
-        {
-            await processor.ProcessSegment(t);
-        }
-        finally
-        {
-            if (processor is IDisposable disposable)
-                disposable.Dispose();
-        }
-    }
-
-    static string BuildOutputFileName(SingleJob job, int index)
-    {
-        string fileName;
-
-        fileName = Path.GetFileName(job.Mask ?? "[NAME]_seg[NN].[EXT]")
-            .Replace("[NAME]", Path.GetFileNameWithoutExtension(job.InputFile))
-            .Replace("[N]"   , index.ToString())
-            .Replace("[NN]"  , index.ToString("00"))
-            .Replace("[NNN]" , index.ToString("000"))
-            .Replace("[NNNN]", index.ToString("0000"))
-            .Replace("[EXT]" , Path.GetExtension(job.InputFile).TrimStart('.'))
-            ;
-
-        return Path.Combine(job.OutputFolder, fileName);
-    }
-
-
-
 }

splitter-cli/splitter.csproj

@@ -9,6 +9,7 @@
     <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
     <PlatformTarget>x64</PlatformTarget>
     <RuntimeIdentifier>win-x64</RuntimeIdentifier>
+    <BuildNumber>0</BuildNumber>
   </PropertyGroup>
 
   <!-- DEBUG CONFIGURATION -->
@@ -49,7 +50,6 @@
 
 
   <ItemGroup>
-    <Compile Update="ThisAssembly.g.cs" />
 
     <Content Include="models/*.*">
       <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>

splitter-cli/tui/ILogger.cs

@@ -1,8 +1,8 @@
-namespace splitter;
+namespace splitter.tui;
 
 public interface ILogger
 {
-    void ClearProgress(int progressLevel);
+    void ClearProgress(string name, int progressLine);
     void DrawProgress(string name, int progressLine, double progress, TimeSpan eta, double speed);
     void Log(string prefix, ConsoleColor color, string msg);
     

splitter-cli/tui/LoggingBase.cs

@@ -1,7 +1,11 @@
-namespace splitter;
+namespace splitter.tui;
 
-public abstract class LoggingBase(ILogger _logger, int _progressLine)
+public abstract class LoggingBase(ILogger logger, int _progressLine)
 {
+#pragma warning disable IDE1006 // Naming Styles
+    protected ILogger _logger = logger;
+#pragma warning restore IDE1006 // Naming Styles
+
     protected void Log(string level, ConsoleColor color, string message)
         => _logger.Log(level, color, message);
 
@@ -17,6 +21,6 @@ public abstract class LoggingBase(ILogger _logger, int _progressLine)
     protected void DrawProgress(string name, double percent, TimeSpan eta, double fps)
         => _logger.DrawProgress(name, _progressLine, percent, eta, fps);
 
-    protected void ClearProgress()
+    protected void ClearProgress(string name)
-        => _logger.ClearProgress(_progressLine);
+        => _logger.ClearProgress(name,_progressLine);
 }

splitter-cli/tui/SpectreConsoleLogger.cs

@@ -2,7 +2,7 @@
 using Spectre.Console;
 using Spectre.Console.Rendering;
 
-namespace splitter;
+namespace splitter.tui;
 
 
 /// <summary>
@@ -51,11 +51,11 @@ public sealed class SpectreConsoleLogger : ILogger, IDisposable
 
     // ---- ILogger ----
 
-    public void ClearProgress(int progressLevel)
+    public void ClearProgress(string name, int progressLine)
     {
         lock (_sync)
         {
-            _progress[progressLevel] = ProgressEntry.Empty;
+            _progress[progressLine] = ProgressEntry.Empty;
         }
     }
 

splitter-cli/tui/TextLogger.cs

@@ -1,4 +1,4 @@
-namespace splitter;
+namespace splitter.tui;
 
 public class TextLogger() : ILogger
 {
@@ -13,6 +13,6 @@ public class TextLogger() : ILogger
     }
 
     public void DrawProgress(string name, int progressLine, double progress, TimeSpan eta, double speed) {}
-    public void ClearProgress(int progressLevel){}
+    public void ClearProgress(string name, int progressLine) {}
 
 }

splitter-cli/util/FileMaskExpander.cs

@@ -1,4 +1,4 @@
-namespace splitter;
+namespace splitter.util;
 
 public static class FileMaskExpander
 {

splitter.slnx

@@ -6,4 +6,5 @@
     <File Path="README.md" />
   </Folder>
   <Project Path="splitter-cli/splitter.csproj" />
+  <Project Path="Splitter-UI/Splitter-UI.csproj" Id="f80bfed3-d5f0-4292-92b2-909c21625ee3" />
 </Solution>