xiry.

Development · Web app

@remotion/webcodecs

In-browser video and audio conversion library powered by the WebCodecs API.

From the Xiry library · Updated 10 October 2026

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An experimental JavaScript package from Remotion designed to process, convert, and manipulate media directly in the browser using the WebCodecs API and GPU acceleration. It handles format transcoding, resizing, rotation, and fixing buggy browser recordings without relying on slower WebAssembly builds. Remotion is currently phasing out this package in favor of Mediabunny.

What it's for

  • Convert video containers and codecs client-side without uploading files to a server
  • Rotate and resize user-uploaded videos directly in the browser
  • Fix missing duration metadata and seeking issues in videos captured via MediaRecorder
  • Extract video frames at specific timestamps for thumbnails or preview generation
  • Resample audio tracks to 16kHz for client-side transcription models like Whisper

Features

  • Client-side video and audio transcoding using native WebCodecs
  • GPU-accelerated processing that outperforms WebAssembly-based FFmpeg ports
  • Format conversion between MP4, WebM, WAV, and others
  • Frame extraction and pixel manipulation tools
  • Video rotation and resizing utilities
  • Audio resampling and track-level stream selection
  • Filesystem integration via File System Access API and ArrayBuffer writing
  • Pause, resume, and abort controllers for conversion jobs

Pricing

Freemium. Free for individuals and teams up to 3; commercial company license required for 4+ people.

Details

Type
Web app
Category
Development
Topic
Video Processing
Open source
No
Platforms
Web, Code library
For
Frontend web developers building client-side video editing and conversion tools.
Alternative to
ffmpeg.wasm
Tags
webcodecs, remotion, video, transcoding, javascript, media

Why it was saved

  • @JNYBGR, 31 August 2025: Second of the two 'FFmpeg for the web' efforts; browser video conversion with convert/resize/rotate/mirror controls.

Related

  • Remotion Convert

    In-browser video and audio conversion running locally without uploads

  • Mediabunny

    Fast, dependency-free JavaScript media toolkit for browser-based video and audio processing

  • webcodecs-scroll-sync

    Synchronize video playback to page scroll using the WebCodecs API

  • Motion

    Open-source animation library for React, Vue, and vanilla JavaScript

  • Anime.js

    Lightweight, modular JavaScript animation engine for CSS, SVG, and DOM elements

  • Remotion Agent Skills

    Agent skills enabling AI coding agents to create programmatic Remotion videos

Updated