38 lines
1.2 KiB
TypeScript
38 lines
1.2 KiB
TypeScript
/*
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Copyright 2021 The Matrix.org Foundation C.I.C.
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Licensed under the Apache License, Version 2.0 (the "License");
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you may not use this file except in compliance with the License.
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You may obtain a copy of the License at
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http://www.apache.org/licenses/LICENSE-2.0
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Unless required by applicable law or agreed to in writing, software
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distributed under the License is distributed on an "AS IS" BASIS,
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WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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See the License for the specific language governing permissions and
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limitations under the License.
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*/
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import { encode } from "blurhash";
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const ctx: Worker = self as any;
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interface IBlurhashWorkerRequest {
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seq: number;
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imageData: ImageData;
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}
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ctx.addEventListener("message", (event: MessageEvent<IBlurhashWorkerRequest>): void => {
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const { seq, imageData } = event.data;
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const blurhash = encode(
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imageData.data,
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imageData.width,
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imageData.height,
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// use 4 components on the longer dimension, if square then both
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imageData.width >= imageData.height ? 4 : 3,
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imageData.height >= imageData.width ? 4 : 3,
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);
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ctx.postMessage({ seq, blurhash });
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});
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