@catlabtech/webcvt-image-jsquash-jxl

JPEG XL (JXL) decode/encode backend for webcvt, wrapping @jsquash/jxl (libjxl in WebAssembly).

JPEG XL is a modern, royalty-free image codec (ISO/IEC 18181) with both lossy and mathematically-lossless modes, progressive decoding, and wide-gamut support.

Installation

npm i @catlabtech/webcvt-image-jsquash-jxl @jsquash/jxl

@jsquash/jxl is an optional peer dependency — installing it is explicit.

Supported conversions

Input	Output
JXL	JXL, PNG, JPEG, WebP
PNG, JPEG, WebP	JXL

Cross-format paths (e.g. PNG→JXL) use a canvas pixel-bridge and therefore need OffscreenCanvas (browsers, workers). JXL→JXL re-encoding works anywhere.

Usage

import { registerJxlBackend } from '@catlabtech/webcvt-image-jsquash-jxl';

// Opt-in registration — no wasm is loaded until the first conversion.
registerJxlBackend();

Then call convert() from @catlabtech/webcvt-core as usual; the JXL backend is selected automatically for the pairs above. Lower-level decodeJxl / encodeJxl free functions are also exported.

Encode options

{
  quality?: number;       // 0–100 (higher = better), default 75
  effort?: number;        // 1–9 (higher = slower/smaller), default 7
  lossless?: boolean;     // default false
  progressive?: boolean;  // default false
}

Notes

• The wasm codec needs script-src 'wasm-unsafe-eval'; the multi-threaded variant additionally needs cross-origin isolation (COOP/COEP) and falls back to the single-threaded codec otherwise.
• Security caps: 256 MiB max input, 25 MP max image (typed errors on violation).

Source

packages/image-jsquash-jxl/src