Function mimeFor

tinyimg: image decoding, transformation and drawing for Cloudflare Workers.

The module has to arrive already compiled, because workerd refuses to compile wasm from bytes. Importing the file is what makes it work there; TinyImgModule.loadBytes is for node, bun and the browser.

import wasm from '@gmitch215/tinyimg/tinyimg.wasm';
import { TinyImgModule, transform } from '@gmitch215/tinyimg';

const tinyimg = TinyImgModule.load(wasm);

export default {
  async fetch(request: Request): Promise<Response> {
    const source = await fetch('https://example.com/photo.jpg');
    const thumb = await transform(tinyimg, source, {
      width: 400,
      height: 400,
      fit: 'cover',
      format: 'webp',
      quality: 80
    });

    return thumb.response();
  }
};
Copy

Three tiers, and they are the same planner underneath:

• transform for one call with an option object, which is most requests.
• Image for a chain, when you want two encodings of one transformation or an operation the option object does not cover.
• TinyImgModule for the things that are not transformations: TinyImgModule.probe, TinyImgModule.detectFaces and TinyImgModule.loadBlob.

Nothing runs until the output is asked for. A 400x400 thumbnail of a 16 megapixel photograph decodes a region at a reduced scale rather than 16 megapixels, and that decision cannot be made after the first operation has already run.