30 lines
698 B
TypeScript
30 lines
698 B
TypeScript
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// Copyright 2021 Signal Messenger, LLC
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// SPDX-License-Identifier: AGPL-3.0-only
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import { IMAGE_JPEG } from '../types/MIME';
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/**
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* Similar to [the built-in `toBlob` method][0], but returns a Promise.
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*
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* [0]: https://developer.mozilla.org/en-US/docs/Web/API/HTMLCanvasElement/toBlob
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*/
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export async function canvasToBlob(
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canvas: HTMLCanvasElement,
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mimeType = IMAGE_JPEG,
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quality?: number
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): Promise<Blob> {
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return new Promise((resolve, reject) =>
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canvas.toBlob(
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result => {
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if (result) {
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resolve(result);
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} else {
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reject(new Error("Couldn't convert the canvas to a Blob"));
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}
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},
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mimeType,
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quality
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)
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);
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}
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