# anime_audio_encoder.py

## Overview

`anime_audio_encoder.py` is a batch-processing script for MKV files, designed for anime encoding workflows. It automates video encoding (with AV1 via SVT-AV1 and `av1an`), audio conversion (to Opus with normalization and optional downmixing), and preserves detailed per-file logs. The script also handles VFR-to-CFR conversion using HandBrakeCLI when needed.

## Features

- **Video encoding**: Uses UTVideo intermediate, VapourSynth, and AV1 encoding via `av1an` and SVT-AV1.
- **Audio processing**: Converts non-Opus/AAC tracks to normalized Opus, with optional downmixing for surround audio.
- **VFR handling**: Detects Variable Frame Rate sources and converts to Constant Frame Rate using HandBrakeCLI.
- **Logging**: Creates a log file for each processed MKV in the `conv_logs` directory.
- **Cleanup**: Moves original files to `original/`, completed files to `completed/`, and deletes temporary files.

## Requirements

The following tools must be installed and available in your `PATH`:

- ffmpeg
- ffprobe
- mkvmerge
- mkvpropedit
- sox
- opusenc
- mediainfo
- av1an
- HandBrakeCLI

## Usage

Place your `.mkv` files in the working directory. Run the script:

```sh
python3 anime_audio_encoder.py
```

### Optional Arguments

- `--no-downmix`  
  Preserve original audio channel layout (do not downmix surround audio to stereo).

  Example:

```sh
python3 anime_audio_encoder.py --no-downmix
```

## Output

- Processed files are moved to the `completed/` directory.
- Originals are moved to the `original/` directory.
- Per-file logs are saved in the `conv_logs/` directory.

## Notes

- The script will skip files that cannot be decoded by ffmpeg.
- Temporary files are cleaned up automatically after processing.
- Scene detection and AV1 encoding may take a long time depending on file size and system performance.

## License

This project is licensed under the MIT License - see the [LICENSE.md](LICENSE.md) file for details.