a simple, effective way to datamosh video clips.
dmosh-bloom.mov
dmosh transcodes video to MPEG-4/AVI with ffmpeg.wasm, edits the raw frame stream, re-encodes to MP4.
It runs the single-threaded ffmpeg core, self-hosted from public/ffmpeg/, so it
works on static hosting (GitHub Pages) with no special headers. Short clips
(a few seconds, ≤~720p) mosh fastest; the engine is memory-bound in the browser.
The MoshBackend seam in src/mosh/backend.ts is where a future native
server-side "heavy mode" would plug in.
Current release: v0.2.0.
v0.2.0 adds the native desktop app (Tauri + a Rust engine, with an ffmpeg sidecar and trial/license gating), a refined light-theme UI with a real-time effect preview, technical effect names, a mosh-range scrubber, keep-audio, and an auto-updating release badge. See CHANGELOG.md for full notes.
| File | Role |
|---|---|
src/mosh/ffmpeg.ts |
Loads + caches the ffmpeg.wasm singleton |
src/mosh/avi.ts |
Parses/writes AVI and classifies MPEG-4 I/P frames |
src/mosh/ops.ts |
Pure bloom / stutter / transition transforms |
src/mosh/datamosh.ts |
Orchestrates transcode -> mosh -> re-encode |
src/mosh/backend.ts |
Routes to the browser, native (Tauri), or server engine |
src/app/MoshApp.tsx |
The single-screen UI |
crates/dmosh-core/ |
Native engine (Rust port of avi/ops + ffmpeg) |
src-tauri/ |
The desktop app shell |
The ffmpeg core is copied from node_modules into public/ffmpeg/ by
scripts/copy-ffmpeg-core.mjs (runs automatically on predev/prebuild); it is
gitignored, not committed.
The web app is free and always will be. The desktop app is the same thing, native: it uses your machine's ffmpeg instead of the in-browser WebAssembly one — so it's much faster and handles large files the browser can't. Two ways to get it, same code either way:
A self-built copy is fully featured, with no license key. Get the latest stable release here. You need
Node, the Rust toolchain, and
ffmpeg.
npm install
npm run tauri:build # → src-tauri/target/release/bundle/
# or: npm run tauri:dev to run it without packagingDon't want to install a toolchain? Buy a prebuilt build — signed, auto-updating, ready to run. It starts as a free trial; after that you paste in a license key to keep going. Paying just saves you the build step and funds development.
Under the hood: the codec effects run through the Rust dmosh-core crate (a port
of avi.ts/ops.ts); the GPU Flow effect runs in the webview. Routing is
automatic (src/mosh/backend.ts detects the Tauri runtime), so the UI is
identical to the web app.
Packaging notes. ffmpeg is bundled as a Tauri sidecar
(scripts/fetch-ffmpeg-sidecar.mjs): win/linux fetch a static build
automatically; on macOS there's no stable static-build URL, so a release
build must supply one via DMOSH_FFMPEG_BIN=/path/to/static/ffmpeg
(e.g. from osxexperts.net or a self-build) — a
plain system ffmpeg is not portable. Official paid builds also bake an Ed25519
public key into src-tauri/src/license.rs (cargo run -p licctl -- keygen) and
compile with --features licensed; self-compiled builds skip all of that.
