Advanced MPV Launcher

A high-performance Rust-based wrapper for mpv.net designed for seamless multi-track audio playback and enhanced video quality. This tool automatically analyzes media files to mix multiple audio streams while preserving the ability to switch back to original tracks.

🚀 Key Features

• Automatic Audio Mixing: Detects multiple audio tracks and plays them simultaneously by default. Perfect for recordings with separate game and voice tracks.
• Smart Audio Switching: Toggle between "Mixed" and "Single" audio modes on the fly using a dedicated hotkey.
• Windows Integration: Built-in commands to register/unregister the launcher in the Windows explorer context menu (Right-click).
• High-Quality Defaults: Forced gpu-hq profile for superior scaling and hwdec=auto-safe for efficient hardware decoding.
• Multi-Instance Support: Every video opens in a new window, preventing playback interruption of existing instances.
• Playlist Awareness: Automatically adds adjacent files in the same folder to the playlist.
• Portable & Robust: Resolves its own resources (FFmpeg, mpv.net, Lua scripts) relative to the executable path.

🛠 Installation

1. Build the project

Ensure you have the Rust toolchain installed, then run:

cargo build --release

2. Context Menu Integration

To add "Open with Advanced MPV" to your Windows right-click menu, run the compiled executable with the --install flag:

.\target\release\mpv-player.exe --install

Note: This modifies the Current User registry (HKCU), so it doesn't require administrator privileges but only affects your user.

3. Uninstallation

To remove the entry from the context menu:

.\target\release\mpv-player.exe --uninstall

🎮 Controls

While playing a video with multiple audio tracks:

• n: Toggle between Mixed Mode (all tracks) and Single Mode (original tracks).
• #: Cycle through individual audio tracks (works in Single Mode).
• Standard mpv keys: All default mpv.net shortcuts remain active.

📂 Project Structure

For the launcher to work correctly, the following folder structure is required:

.
├── mpv-player.exe (Launcher)
└── bin/
    ├── audio_mixer.lua      (Core logic for mixing)
    ├── mpv.net/             (Contains mpvnet.exe and dependencies)
    └── ffmpeg-essentials/   (Contains ffprobe.exe for analysis)

🧠 How It Works

1. Pre-flight Check: When a file is opened, the launcher uses ffprobe to scan for the number of audio streams.
2. Dynamic Injection: If multiple tracks are found, it injects a custom Lua script and passes the stream count via script-opts.
3. Live Mixing: The Lua script uses lavfi-complex with an amix filter to combine audio on the fly without re-encoding.
4. Context Switching: The n key dynamically resets the lavfi-complex property to allow standard mpv track selection.

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Developed as a specialized engineering tool for advanced media handling.