Render pdf to fixed size?

I’m currently writing an Electron app, which needs to get the rgba pixel data from PDF files. Now the below code I have is working fine, but I was wondering if it’s possible to render the pdf to a specific size?

This would probably(?) make processing large PDF files faster, as I only need 64x64worth of pixel data.

const create2dContext = (width, height) => {
  const canvas = document.createElement("canvas");
  canvas.width = width;
  canvas.height = height;
  return canvas.getContext("2d");
};

const decodePdf = async (imagePath) => {
  const pdf = await PDFJS.getDocument(imagePath);
  const page = await pdf.getPage(1);

  const viewport = page.getViewport(1);
  const { width, height } = viewport;

  const canvasContext = create2dContext(width, height);
  await page.render({ canvasContext, viewport });

  return canvasContext.getImageData(0, 0, width, height);
};

[Snuffleupagus]

You’ll need to resize the viewport as well; look at how the thumbnail canvas size is set in https://github.com/mozilla/pdf.js/blob/309b6f820e5250e6290f1fb986c7c92f7a1431cd/web/pdf_thumbnail_view.js#L106-L112 and how the scale of the viewport is then changed in https://github.com/mozilla/pdf.js/blob/309b6f820e5250e6290f1fb986c7c92f7a1431cd/web/pdf_thumbnail_view.js#L316 before rendering is triggered in https://github.com/mozilla/pdf.js/blob/309b6f820e5250e6290f1fb986c7c92f7a1431cd/web/pdf_thumbnail_view.js#L329-L333

[Glinkis]

My solution is currently to scale the smallest axis down to 64, and then scale the other one proportionally.

And then I squish the image at a later stage. This is a decent tradeoff, and certainly saves some memory compared to previously.

However, if I could scale the initial render, I would avoid the extra memory allocation of the intermediate step.