# ZoomCutter

Automatically process Zoom recordings to switch between speaker-only and side-by-side views based on screen sharing chapters.

## What it does

ZoomCutter intelligently combines your Zoom camera and screen sharing recordings into a single video that:
- Shows **speaker-only view** when you're not sharing your screen
- Switches to your chosen layout (side-by-side or diagonal) when screen sharing is detected
- Supports multiple layout options and custom backgrounds
- Maintains camera's native resolution for optimal performance
- Uses Zoom's built-in chapter markers to detect sharing automatically

Perfect for creating professional-looking recordings of presentations, lectures, or meetings!

## Layout Examples

### Side-by-Side Layout
50/50 split with slides on the left and camera on the right - perfect for balanced presentations.

![Side-by-Side Layout Example](examples/screenshot-side-by-side.png)

### Diagonal Layout
Large slides (~72% width) with a small camera overlay in the bottom-right corner - ideal for slide-heavy content.

![Diagonal Layout Example](examples/screenshot-diagonal.png)

## Features

- **Automatic switching**: Reads Zoom chapter markers to detect when screen sharing starts/stops
- **Smart resolution handling**: Uses camera's native resolution by default (no unnecessary upscaling)
- **Custom dimensions**: Optional override to set specific output resolution (e.g., 1080p, 720p)
- **Multiple layouts**: Choose between side-by-side (50/50 split) or diagonal (large slides with small camera overlay)
- **Custom backgrounds**: Set background color or use custom background images
- **Trim support**: Cut your video to specific start/end times
- **Fast processing**: Optimized ffmpeg settings for quick encoding
- **Dry-run mode**: Preview the ffmpeg command before processing

## Installation

```bash
pip install zoomcutter
```

## Run without installing

```bash
uvx zoomcutter --help
```

### Requirements

ZoomCutter requires **ffmpeg** to be installed on your system:

**macOS:**
```bash
brew install ffmpeg
```

**Ubuntu/Debian:**
```bash
sudo apt install ffmpeg
```

**Windows:**
Download from [ffmpeg.org](https://ffmpeg.org/download.html) or use [Chocolatey](https://chocolatey.org/):
```bash
choco install ffmpeg
```

## Usage

### Basic Usage

```bash
zoomcutter camera_file.mp4 slides_file.mp4 output.mp4
```

Where:
- `camera_file.mp4` - Your Zoom camera recording (usually named `*_avo_*.mp4`)
- `slides_file.mp4` - Your Zoom screen sharing recording (usually named `*_as_*.mp4`)
- `output.mp4` - The output filename

### Trim Video

Cut your video to a specific time range:

```bash
# Start at 2 minutes, end at 45 minutes
zoomcutter camera.mp4 slides.mp4 output.mp4 --start 00:02:00 --end 00:45:00

# Using short options
zoomcutter camera.mp4 slides.mp4 output.mp4 -ss 00:02:00 -to 00:45:00
```

### Custom Output Dimensions

Set custom output dimensions instead of using the camera's native resolution:

```bash
# Output at 1080p (1920x1080) even if camera is 720p
zoomcutter camera.mp4 slides.mp4 output.mp4 --dimensions 1080p

# Or specify exact dimensions
zoomcutter camera.mp4 slides.mp4 output.mp4 -d 1920x1080

# Common presets: 1080p, 720p, 480p
# Or any custom WIDTHxHEIGHT format
```

**Note**: This will scale the video to the specified dimensions. Upscaling (e.g., 720p to 1080p) may reduce quality, while downscaling can reduce file size.

### Dry Run

Preview the ffmpeg command without processing:

```bash
zoomcutter camera.mp4 slides.mp4 output.mp4 --dry-run
```

### Layout Options

Choose between different layout modes for when screen sharing is active:

#### Side-by-Side Layout (default)
```bash
zoomcutter camera.mp4 slides.mp4 output.mp4 --layout side-by-side
# Or short form:
zoomcutter camera.mp4 slides.mp4 output.mp4 -l side-by-side
```
- 50/50 split: slides on left, camera on right
- Equal space for both elements
- Classic presentation layout

#### Diagonal Layout
```bash
zoomcutter camera.mp4 slides.mp4 output.mp4 --layout diagonal
# Or short form:
zoomcutter camera.mp4 slides.mp4 output.mp4 -l diagonal
```
- Large slides (~72% width) on the left
- Small camera overlay in bottom-right corner
- Minimal content overlap
- Great for slide-heavy presentations

### Background Customization

Customize the background color or use a custom image:

#### Custom Background Color
```bash
# Use a named color
zoomcutter camera.mp4 slides.mp4 output.mp4 --background-color white

# Use a hex color
zoomcutter camera.mp4 slides.mp4 output.mp4 --background-color "#1E3A8A"

# Short form:
zoomcutter camera.mp4 slides.mp4 output.mp4 -bg "#FF5733"
```

#### Background Image
```bash
# Use a custom background image
zoomcutter camera.mp4 slides.mp4 output.mp4 --background-image /path/to/background.jpg

# Short form:
zoomcutter camera.mp4 slides.mp4 output.mp4 -bgi background.png
```

#### Combine Options
```bash
# Diagonal layout with custom background
zoomcutter camera.mp4 slides.mp4 output.mp4 \
  --layout diagonal \
  --background-color "#2C3E50" \
  --start 00:05:00 \
  --end 01:30:00
```

## How It Works

1. **Reads chapter markers**: ZoomCutter analyzes the screen sharing video file to find "Sharing Started" and "Sharing Stopped" chapter markers that Zoom automatically adds
2. **Detects camera resolution**: Uses the camera feed's native resolution for optimal quality
3. **Builds filter**: Creates an ffmpeg filter that:
   - Shows camera at full resolution when not sharing (speaker-only mode)
   - Switches to your chosen layout during sharing:
     - **Side-by-side**: 50/50 split with slides on left, camera on right
     - **Diagonal**: Large slides with small camera overlay in bottom-right
   - Applies custom background colors or images if specified
4. **Processes video**: Runs ffmpeg with optimized settings for fast, high-quality output

## Output Quality

- **Video codec**: H.264 with CRF 18 (high quality)
- **Preset**: veryfast (good balance of speed and compression)
- **Audio**: Copied directly from camera feed (no re-encoding)
- **Resolution**: Matches camera's native resolution

## Example

```bash
# Process a 1-hour Zoom recording
$ zoomcutter zoom_0.mp4 zoom_share.mp4 final.mp4

Processing Zoom recordings...
  Camera: zoom_0.mp4
  Slides: zoom_share.mp4
  Output: final.mp4

Camera resolution: 1920x1080

Found 12 chapters
Found 3 screen sharing intervals:
  1. 120.50s - 850.30s
  2. 1200.00s - 2400.50s
  3. 2800.00s - end

Output resolution: 1920x1080 (camera native)
  - Speaker-only mode: No scaling (maximum performance!)
  - Side-by-side mode: Only scales slides down

Running ffmpeg...

 Successfully created: final.mp4
```

## Troubleshooting

**Error: "Could not detect camera resolution"**
- Make sure the camera file is a valid video file
- Try running `ffprobe camera_file.mp4` to verify

**Error: "Error running ffprobe"**
- Ensure ffmpeg (which includes ffprobe) is installed and in your PATH

**No chapters found**
- Verify you're using the screen sharing file (`*_as_*.mp4`) for chapter detection
- Some older Zoom versions may not include chapters

## Development

### Setup

```bash
git clone https://github.com/weltonrodrigo/zoomcutter.git
cd zoomcutter
uv pip install -e .
```

### Run locally

```bash
python main.py camera.mp4 slides.mp4 output.mp4
```

## License

MIT License - see LICENSE file for details

## Contributing

Contributions are welcome! Please feel free to submit a Pull Request.
