squoosh/codecs

Codecs

This folder contains a self-contained sub-project for each codec that squoosh supports.

Build

Each subproject can be built using the following commands:

$ npm install
$ npm run build

This will build two files: <codec name>_codec.js and <codec name>_codec.wasm. Due to some current limitations in Emscripten, both of these files have to be served from the root folder. When the .js file is loaded, a global <codec name> is created with the same API as an Emscripten Module.

Each codec offers at least 2 functions:

• void encode(uint8_t* img_in, int width, int height, float quality)
• void decode(???)

Example:

<!-- *_codec.{wasm,js} need to be in / -->
<script src="/mozjpeg_codec.js"></script>
<script>
  mozjpeg.onRuntimeInitialized = _ => {
    const encode = mozjpeg.cwrap('encode', '', ['number', 'number', 'number', 'number']);
    /* ... */
  };
</script>