ffmpeg-webassembly-workers

## CRITICAL GUIDELINES

### Windows File Path Requirements

**MANDATORY: Always Use Backslashes on Windows for File Paths**

When using Edit or Write tools on Windows, you MUST use backslashes (`\`) in file paths, NOT forward slashes (`/`).

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## Quick Reference

| Package | Size | Threading | Install |
|---------|------|-----------|---------|
| `@ffmpeg/core` | ~31MB | Single | `npm install @ffmpeg/ffmpeg @ffmpeg/util` |
| `@ffmpeg/core-mt` | ~31MB | Multi | Requires COOP/COEP headers |

| Header | Value | Purpose |
|--------|-------|---------|
| Cross-Origin-Embedder-Policy | `require-corp` | SharedArrayBuffer |
| Cross-Origin-Opener-Policy | `same-origin` | Multi-threading |

| Operation | Command |
|-----------|---------|
| Convert WebM→MP4 | `await ffmpeg.exec(['-i', 'input.webm', 'output.mp4'])` |
| Extract frame | `await ffmpeg.exec(['-i', 'video.mp4', '-ss', '5', '-vframes', '1', 'thumb.jpg'])` |

## When to Use This Skill

Use for **browser-based video processing**:
- Client-side transcoding without server
- React/Vue/Next.js FFmpeg integration
- Setting up COOP/COEP headers
- Cloudflare Workers FFmpeg limitations
- Memory management and cleanup

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# FFmpeg WebAssembly & Cloudflare Workers (2025)

Guide to running FFmpeg in browsers and edge environments using WebAssembly.

## ffmpeg.wasm Overview

**ffmpeg.wasm** is a pure WebAssembly/JavaScript port of FFmpeg that runs directly in browsers without server-side processing.

### Key Features
- **Browser-based**: No server required for video processing
- **Cross-platform**: Works on any modern browser
- **Single-thread**: @ffmpeg/core (~31MB)
- **Multi-thread**: @ffmpeg/core-mt (requires SharedArrayBuffer)
- **Customizable**: Build your own core with specific codecs

### Limitations
- **Performance**: ~10-100x slower than native FFmpeg
- **Memory**: Limited by browser memory constraints
- **File size**: Core is ~31MB (can be reduced with custom builds)
- **Threading**: Multi-thread requires specific hea