26 lines
816 B
TypeScript
26 lines
816 B
TypeScript
// Copyright 2022 Signal Messenger, LLC
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// SPDX-License-Identifier: AGPL-3.0-only
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import { encode } from 'blurhash';
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/**
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* This generates a blurhash for a single pixel of a given color.
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*
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* The color is specified as an ARGB value, where the alpha channel is ignored.
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*/
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export function generateBlurHash(argb: number = 0xff_fbfbfb): string {
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return encode(
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new Uint8ClampedArray([
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/* eslint-disable no-bitwise */
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// Flipping from argb to rgba
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0xff & (argb >> 16), // R
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0xff & (argb >> 8), // G
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0xff & (argb >> 0), // B
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0xff, // A (ignored)
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/* eslint-enable no-bitwise */
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]),
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1, // width (data is just one pixel)
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1, // height (data is just one pixel)
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1, // x components (just the average color)
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1 // y components (just the average color)
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);
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}
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