# Electron MP4 Render Manual Checks

Date: 2026-06-05

Use this checklist before treating desktop MP4 export as release-ready.

## Automated Desktop Render Checks

Before the manual checks below, run the headless harness suite (requires a
display, ffmpeg, and ffprobe). It drives the real worker end-to-end and covers
frame capture, MP4 output, cancel, the inactivity watchdog, the render-window
network block, and transparent-region flattening:

```bash
npm run test:render-desktop
```

All six checks should print `RESULT: PASS` and the run ends with
`ALL DESKTOP RENDER CHECKS PASSED`.

## Build Checks

1. Stage a redistributable ffmpeg binary for the target platform:

   ```bash
   npm run stage:ffmpeg -- --source /path/to/ffmpeg
   ```

2. Build an unpacked app:

   ```bash
   npm run desktop:pack
   ```

3. Confirm packaged resources exist:

   ```bash
   find release/linux-unpacked/resources -maxdepth 4 -type f | sort | rg 'server/render.html|bin/.*/ffmpeg'
   ```

4. Confirm Unix executable permissions on Linux/macOS:

   ```bash
   ls -l release/linux-unpacked/resources/bin/linux/ffmpeg
   ```

5. Confirm the packaged binary runs:

   ```bash
   release/linux-unpacked/resources/bin/linux/ffmpeg -version
   ```

## App Checks

1. Launch the unpacked app.
2. Create a tiny scene with at least one visible animated layer.
3. Export MP4 at the default FPS and confirm:
   - a native save dialog appears
   - progress advances in the export dialog
   - the final file exists at the selected path
   - the file opens in a standard media player
4. Start another MP4 export and cancel after progress starts. Confirm:
   - progress stops
   - the app remains responsive
   - no partial MP4 remains at the selected path
5. Repeat with:
   - image assets
   - text layers using non-default fonts
   - non-default FPS
   - layers hidden from render

## Server Fallback Checks

Automated route smoke:

```bash
npm run test:render-server
```

Automated MP4 E2E smoke:

```bash
npm run test:render-server:e2e
```

The E2E smoke starts the standalone server on a temporary localhost port,
submits a tiny scene, waits for SSE completion, downloads the MP4, and verifies
the H.264 stream with `ffprobe`. It requires Chromium, ffmpeg, and ffprobe.

Manual browser fallback:

1. Start the standalone server:

   ```bash
   cd server
   HOST=127.0.0.1 PORT=6000 RENDER_TOKEN="choose-a-long-random-token" npm start
   ```

2. Start the browser app with matching render settings:

   ```bash
   VITE_RENDER_SERVER=http://localhost:6000 VITE_RENDER_TOKEN="choose-a-long-random-token" npm run dev
   ```

3. Export MP4 from the browser app and confirm the server path still works.

## ffmpeg Release Notes

For every bundled ffmpeg binary, record:

- source URL
- upstream version
- target platform and architecture
- whether the build is static or dynamically linked
- configured codecs, especially `libx264`
- GPL/LGPL license obligations
- required attribution or license files to ship with the app

The local staging script may copy a system ffmpeg. That is useful for package
path verification, but release artifacts should use reviewed redistributable
binaries for each platform.