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/* |
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* riff |
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* Get the chunks of a RIFF file. |
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* TODO: This should be a npm package on its own. |
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* Copyright (c) 2017 Rafael da Silva Rocha. MIT License. |
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* https://github.com/rochars/wavefile |
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* |
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*/ |
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const byteData = require("byte-data"); |
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/** |
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* Get the chunks of a RIFF file. |
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* @param {Uint8Array|!Array<number>} buffer the RIFF file bytes. |
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* @param {boolean} bigEndian true if its RIFX. |
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* @return {object} |
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*/ |
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function getChunks(buffer, bigEndian) { |
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// RIFF container |
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let chunkId = byteData.fromBytes( |
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buffer.slice(0, 4), 8, {"char": true} |
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); |
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let chunkSize = byteData.fromBytes( |
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buffer.slice(4, 8), 32, {'be': bigEndian} |
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)[0]; |
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let format = byteData.fromBytes( |
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buffer.slice(8, 12), 8, {"char": true} |
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); |
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let chunks = []; |
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let len = buffer.length; |
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let i = 12; |
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while(i < len) { |
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let subChunkSize = byteData.fromBytes( |
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buffer.slice(i + 4, i + 8), 32, {'be': bigEndian})[0]; |
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chunks.push({ |
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"subChunkId": byteData.fromBytes(buffer.slice(i, i + 4), 8, {"char": true}), |
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"subChunkSize": subChunkSize, |
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"subChunkData": buffer.slice(i + 8, i + 8 + subChunkSize) |
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}); |
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i = i + 8 + subChunkSize; |
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} |
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return { |
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"chunkId": chunkId, |
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"chunkSize": chunkSize, |
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"format": format, |
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"subChunks": chunks |
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} |
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} |
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module.exports.getChunks = getChunks; |
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rochars /
wavefile
