immich/web/src/lib/actions/thumbhash.ts

20 lines
660 B
TypeScript

import { decodeBase64 } from '$lib/utils';
import { thumbHashToRGBA } from 'thumbhash';
/**
* Renders a thumbnail onto a canvas from a base64 encoded hash.
* @param canvas
* @param param1 object containing the base64 encoded hash (base64Thumbhash: yourString)
*/
export function thumbhash(canvas: HTMLCanvasElement, { base64ThumbHash }: { base64ThumbHash: string }) {
const ctx = canvas.getContext('2d');
if (ctx) {
const { w, h, rgba } = thumbHashToRGBA(decodeBase64(base64ThumbHash));
const pixels = ctx.createImageData(w, h);
canvas.width = w;
canvas.height = h;
pixels.data.set(rgba);
ctx.putImageData(pixels, 0, 0);
}
}