OffscreenCanvas not supported by this browser for server-side worker

[korywka]

System Info

transformers: 3.6.2
deno: 2.4.1

Environment/Platform

• Website/web-app
• Browser extension
• Server-side (e.g., Node.js, Deno, Bun)
• Desktop app (e.g., Electron)
• Other (e.g., VSCode extension)

Description

Using Deno and running transformers.js inside WebWorker tries to call OffscreenCanvas:

if (IS_BROWSER_OR_WEBWORKER) {
    // Running in browser or web-worker
    createCanvasFunction = (/** @type {number} */ width, /** @type {number} */ height) => {
        if (!self.OffscreenCanvas) {
            throw new Error('OffscreenCanvas not supported by this browser.');
        }
        return new self.OffscreenCanvas(width, height)
    };
    loadImageFunction = self.createImageBitmap;
    ImageDataClass = self.ImageData;

}

But Deno doesn't support OffscreenCanvas. Can we skip this condition for Deno? This issue started after update of the package version. On old version of transformers.js it was running without any error for Deno. Thanks.

Reproduction

calling const image = await RawImage.fromURL(...);

[korywka]

Looks like node also doesn't support OffscreenCanvas. So should the condition only for browser be enough?

[korywka]

Any ideas? Don't you mind a PR to remove web worker environment for OffscreenCanvas?

[xenova]

Hi there 👋 OffscreenCanvas is quite useful when running in-browser via web workers, so a PR to fully remove it sounds a bit excessive.

That said, perhaps adding a check here for Deno could work, since in that case, we'll just disallow image manipulation operations.

Also, if you could provide a code snippet to reproduce the error you're facing, that would be great!