SoundGIF

SoundGIF stores compressed audio inside a GIF file. Normal GIF viewers ignore the audio data and display the animation. SoundGIF-aware apps and plugins find the embedded data, verify it, and play it with the animation.

The project contains:

• A Rust desktop app for creating and playing SoundGIF files.
• A Rust command-line tool for embedding, extracting, inspecting, and removing audio.
• A Vencord plugin that plays SoundGIF attachments inside Discord.

Repository layout

src/                         Rust library, CLI, desktop app, and UI
tests/                       CLI integration tests
plugins/vencord/soundGif/    Discord/Vencord plugin

Other social-platform integrations can be added under plugins/ without coupling them to the encoder.

Desktop app

The desktop app accepts:

• MP4, M4V, MOV, WebM, MKV, and AVI files for conversion.
• Existing GIF files for SoundGIF playback and inspection.

Conversion uses FFmpeg. SoundGIF first tries to copy compatible audio without re-encoding it. If that is not possible, it falls back to variable-bitrate Opus. GIF frames use a generated palette, rectangle-difference updates, and configurable size and frame-rate limits.

The Original profile keeps the video's dimensions and frame timing. Compact, Balanced, and High quality apply limits instead. Advanced settings accept a custom frame rate, width limit, palette size, and Opus fallback bitrate.

Build both executables:

cargo build --release --bins

The results are:

target/release/soundgif
target/release/soundgif-player

Windows adds the .exe suffix.

Platform requirements

• Windows: Microsoft Edge WebView2 Runtime.
• macOS: the built-in WKWebView.
• Linux: WebKitGTK 4.1 and GTK 3.

SoundGIF uses an existing FFmpeg install from beside the app, PATH, or common install locations. If it cannot find one during a conversion, it installs FFmpeg with WinGet on Windows, Homebrew on macOS, or the system package manager on Linux. macOS needs Homebrew. Linux may show an authentication prompt.

Ubuntu/Debian build dependencies:

sudo apt install libwebkit2gtk-4.1-dev

The CLI and file format do not depend on a desktop webview.

Release assets include Windows x64, a universal macOS build for Apple Silicon and Intel, and Linux x64. The macOS app is not code-signed, so the first launch may require approval in System Settings > Privacy & Security.

CLI

Create a SoundGIF from video:

soundgif from-video clip.mp4 -o clip.sound.gif

Embed an existing audio stream:

soundgif embed animation.gif sound.opus -o animation-with-sound.gif

Inspect, extract, or remove embedded audio:

soundgif inspect animation-with-sound.gif
soundgif extract animation-with-sound.gif -o recovered.opus
soundgif strip animation-with-sound.gif -o animation-silent.gif

Run soundgif help for conversion and playback options.

Vencord plugin

The Vencord package includes rerunnable installers:

• Windows: double-click install-windows.cmd.
• macOS: double-click install-macos.command.
• Linux: run bash install-linux.sh.

Each installer is one standalone file. Each run updates the SoundGIF and Vencord source checkouts, restores Vencord/src/userplugins/soundGif, rebuilds Vencord, and runs Vencord's injector. This also repairs the custom build if a later Vencord update replaces it. Restart Discord and enable SoundGIF in Vencord settings afterward.

The installer menu can enable a per-user automatic check. It runs at sign-in and every 15 minutes, rebuilds when SoundGIF or Vencord changed, and repairs the selected Stable, PTB, or Canary Discord install if its Vencord patch is gone. The same menu can disable and remove the scheduled check.

Git, Node.js, and pnpm are required because Vencord does not load external user plugins without being built from source.

The plugin detects the SoundGIF application block inside the file. It does not depend on a special filename. It keeps GIF and audio loops on one timeline, pauses when the GIF is not playing, applies safe default volume and peak limiting, and provides a per-attachment mute control.

The plugin treats embedded data only as media. It rejects oversized files, reads network responses with a hard byte limit, verifies the payload structure and CRC-32, accepts only known audio MIME types, and passes the result to Chromium's media decoder. It does not evaluate embedded code.

File format

Audio is stored before the GIF trailer in a GIF89a Application Extension.

Field	Value
Application identifier	SNDGIF01
Authentication code	001
Payload magic	SGA1
Payload version	1

The payload contains playback flags, audio start offset, byte length, CRC-32, MIME type, original filename, and compressed audio bytes. It is split into standard GIF data sub-blocks of at most 255 bytes.

Services that resize or re-encode GIF uploads can remove the application extension. Direct file uploads work only when the service preserves the original GIF bytes.

Development

Run the local checks:

cargo fmt --all -- --check
cargo clippy --all-targets -- -D warnings
cargo test --all-targets

The GitHub Actions workflow checks Windows, macOS, and Linux builds.

Licenses

The Rust app and SoundGIF format implementation are MIT licensed. The Vencord plugin is GPL-3.0-or-later because it is built against Vencord.