Switch to blurhash-react instead of homegrown component

this has the advantage of resolution scaling logic to do more gpu accelerated scaling

package.json

@@ -92,6 +92,7 @@
     "re-resizable": "^6.9.0",
     "react": "^17.0.2",
     "react-beautiful-dnd": "^13.1.0",
+    "react-blurhash": "^0.1.3",
     "react-dom": "^17.0.2",
     "react-focus-lock": "^2.5.0",
     "react-transition-group": "^4.4.1",

src/components/views/elements/BlurhashPlaceholder.tsx

@@ -1,56 +0,0 @@
-/*
- Copyright 2020 The Matrix.org Foundation C.I.C.
-
- Licensed under the Apache License, Version 2.0 (the "License");
- you may not use this file except in compliance with the License.
- You may obtain a copy of the License at
-
- http://www.apache.org/licenses/LICENSE-2.0
-
- Unless required by applicable law or agreed to in writing, software
- distributed under the License is distributed on an "AS IS" BASIS,
- WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- See the License for the specific language governing permissions and
- limitations under the License.
- */
-
-import React from 'react';
-import { decode } from "blurhash";
-
-interface IProps {
-    blurhash: string;
-    width: number;
-    height: number;
-}
-
-export default class BlurhashPlaceholder extends React.PureComponent<IProps> {
-    private canvas: React.RefObject<HTMLCanvasElement> = React.createRef();
-
-    public componentDidMount() {
-        this.draw();
-    }
-
-    public componentDidUpdate() {
-        this.draw();
-    }
-
-    private draw() {
-        if (!this.canvas.current) return;
-
-        try {
-            const { width, height } = this.props;
-
-            const pixels = decode(this.props.blurhash, Math.ceil(width), Math.ceil(height));
-            const ctx = this.canvas.current.getContext("2d");
-            const imgData = ctx.createImageData(width, height);
-            imgData.data.set(pixels);
-            ctx.putImageData(imgData, 0, 0);
-        } catch (e) {
-            console.error("Error rendering blurhash: ", e);
-        }
-    }
-
-    public render() {
-        return <canvas height={this.props.height} width={this.props.width} ref={this.canvas} />;
-    }
-}

src/components/views/messages/MImageBody.js

@@ -18,6 +18,7 @@ limitations under the License.
 
 import React, { createRef } from 'react';
 import PropTypes from 'prop-types';
+import { Blurhash } from "react-blurhash";
 
 import MFileBody from './MFileBody';
 import Modal from '../../../Modal';
@@ -29,7 +30,6 @@ import MatrixClientContext from "../../../contexts/MatrixClientContext";
 import InlineSpinner from '../elements/InlineSpinner';
 import { replaceableComponent } from "../../../utils/replaceableComponent";
 import { mediaFromContent } from "../../../customisations/Media";
-import BlurhashPlaceholder from "../elements/BlurhashPlaceholder";
 import { BLURHASH_FIELD } from "../../../ContentMessages";
 
 @replaceableComponent("views.messages.MImageBody")
@@ -436,7 +436,7 @@ export default class MImageBody extends React.Component {
     // Overidden by MStickerBody
     getPlaceholder(width, height) {
         const blurhash = this.props.mxEvent.getContent().info[BLURHASH_FIELD];
-        if (blurhash) return <BlurhashPlaceholder blurhash={blurhash} width={width} height={height} />;
+        if (blurhash) return <Blurhash hash={blurhash} width={width} height={height} />;
         return <div className="mx_MImageBody_thumbnail_spinner">
             <InlineSpinner w={32} h={32} />
         </div>;

yarn.lock

@@ -6454,6 +6454,11 @@ react-beautiful-dnd@^13.1.0:
     redux "^4.0.4"
     use-memo-one "^1.1.1"
 
+react-blurhash@^0.1.3:
+  version "0.1.3"
+  resolved "https://registry.yarnpkg.com/react-blurhash/-/react-blurhash-0.1.3.tgz#735f28f8f07fb358d7efe7e7e6dc65a7272bf89e"
+  integrity sha512-Q9lqbXg92NU6/2DoIl/cBM8YWL+Z4X66OiG4aT9ozOgjBwx104LHFCH5stf6aF+s0Q9Wf310Ul+dG+VXJltmPg==
+
 react-clientside-effect@^1.2.2:
   version "1.2.3"
   resolved "https://registry.yarnpkg.com/react-clientside-effect/-/react-clientside-effect-1.2.3.tgz#95c95f520addfb71743608b990bfe01eb002012b"