# Audio Extractor

A Python tool for extracting and managing audio tracks from video files using FFmpeg.

## Features

- **Extract Audio**: Extract all audio channels from video files as individual files
- **Preserve Quality**: Maintains original bitrate and codec without re-encoding
- **Batch Processing**: Process multiple video files from a folder
- **Multi-track Support**: Automatically handles videos with multiple audio tracks
- **Flexible Output**: Specify custom output folder

## Future Features

- **Add Tracks**: Add individual audio files as new tracks to video files
- **Track Titles**: Assign custom titles/names to audio tracks
- **Batch Operations**: Apply operations to multiple files with matching base names

## Installation

### Prerequisites

- Python 3.6+
- FFmpeg installed and accessible in your PATH
- FFprobe (usually included with FFmpeg)

### Install FFmpeg

**macOS** (using Homebrew):
```bash
brew install ffmpeg
```

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

**Windows** (using Chocolatey):
```bash
choco install ffmpeg
```

Or download from: https://ffmpeg.org/download.html

## Usage

### Extract Audio from a Single Video

```bash
python main.py extract "path/to/video.mp4" -o ./audio_output
```

### Extract Audio from All Videos in a Folder

```bash
python main.py extract "./videos_folder" -o ./audio_output
```

### Legacy Command Format

The tool also supports the original command format:

```bash
python main.py --extract "target" -o output_folder
```

## Examples

**Extract from single file:**
```bash
python main.py extract "movie.mp4" -o ./extracted_audio
```

**Extract from entire folder:**
```bash
python main.py extract "./my_videos" -o "./audio_tracks"
```

**Extract with default output folder (./audio_output):**
```bash
python main.py extract "video.mkv"
```

## How It Works

1. **Identifies video files** in the target path
2. **Analyzes audio streams** using ffprobe to detect codec and bitrate information
3. **Extracts each audio track** using FFmpeg's codec copy mode (no re-encoding)
4. **Preserves quality** by maintaining original bitrate and codec
5. **Names files** appropriately based on source video and track number

## Output

Extracted audio files are saved with the following naming:

- **Single audio track**: `video_name.aac` (or appropriate extension)
- **Multiple audio tracks**: `video_name_audio_0.aac`, `video_name_audio_1.aac`, etc.

## Troubleshooting

**"ffmpeg is not installed or not found in PATH"**
- Ensure FFmpeg is installed and the `ffmpeg` command is accessible from your terminal
- Test with: `ffmpeg -version`

**"No audio streams found"**
- The video file may not contain any audio tracks
- Try analyzing the file with: `ffprobe "video.mp4"`

**Extraction fails**
- Check that the video file is not corrupted
- Try opening it with a media player first
- Check disk space in the output folder

## Development

### Project Structure

```
audio-extractor/
├── main.py              # Entry point and CLI argument parsing
├── audio_extractor/
│   ├── __init__.py
│   ├── cli.py          # CLI interface
│   └── extractor.py    # Core extraction logic
├── requirements.txt
└── README.md
```

### Adding Features

To add new features:

1. Add command logic to `audio_extractor/extractor.py`
2. Add CLI interface to `audio_extractor/cli.py`
3. Add new command to the argument parser in `main.py`

## License

MIT