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/* |
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* Copyright (c) 2017-2019 Rafael da Silva Rocha. |
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* |
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* Permission is hereby granted, free of charge, to any person obtaining |
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* a copy of this software and associated documentation files (the |
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* "Software"), to deal in the Software without restriction, including |
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* without limitation the rights to use, copy, modify, merge, publish, |
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* distribute, sublicense, and/or sell copies of the Software, and to |
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* permit persons to whom the Software is furnished to do so, subject to |
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* the following conditions: |
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* |
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* The above copyright notice and this permission notice shall be |
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* included in all copies or substantial portions of the Software. |
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* |
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, |
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* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF |
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* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND |
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* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE |
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* LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION |
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* OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION |
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* WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. |
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* |
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*/ |
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/** |
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* @fileoverview The WaveFileCreator class. |
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* @see https://github.com/rochars/wavefile |
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*/ |
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import { WaveFileParser } from 'wavefile-parser'; |
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import { packArrayTo } from 'byte-data'; |
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/** @module wavefile-creator */ |
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/** |
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* A class to read, write and create wav files. |
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* @extends WaveFileParser |
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*/ |
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export class WaveFileCreator extends WaveFileParser { |
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/** |
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* @param {?Uint8Array=} wavBuffer A wave file buffer. |
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* @param {boolean=} samples True if the samples should be loaded. |
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* @throws {Error} If container is not RIFF, RIFX or RF64. |
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* @throws {Error} If format is not WAVE. |
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* @throws {Error} If no 'fmt ' chunk is found. |
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* @throws {Error} If no 'data' chunk is found. |
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*/ |
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constructor(wavBuffer=null, samples=true) { |
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// Dont load the file yet |
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super(); |
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/** |
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* The bit depth code according to the samples. |
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* @type {string} |
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*/ |
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this.bitDepth = '0'; |
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/** |
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* @type {{ |
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be: boolean, |
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bits: number, |
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fp: boolean, |
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signed: boolean |
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}} |
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* @protected |
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*/ |
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this.dataType = { |
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be: false, |
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bits: 0, |
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fp: false, |
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signed: false |
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}; |
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/** |
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* Audio formats. |
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* Formats not listed here should be set to 65534, |
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* the code for WAVE_FORMAT_EXTENSIBLE |
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* @enum {number} |
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* @protected |
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*/ |
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this.WAV_AUDIO_FORMATS = { |
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'4': 17, |
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'8': 1, |
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'8a': 6, |
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'8m': 7, |
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'16': 1, |
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'24': 1, |
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'32': 1, |
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'32f': 3, |
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'64': 3 |
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}; |
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// Now load the file |
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if (wavBuffer) { |
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this.fromBuffer(wavBuffer, samples); |
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} |
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} |
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/** |
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* Set up the WaveFileCreator object from a byte buffer. |
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* @param {!Uint8Array} wavBuffer The buffer. |
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* @param {boolean=} samples True if the samples should be loaded. |
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* @throws {Error} If container is not RIFF, RIFX or RF64. |
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* @throws {Error} If format is not WAVE. |
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* @throws {Error} If no 'fmt ' chunk is found. |
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* @throws {Error} If no 'data' chunk is found. |
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*/ |
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fromBuffer(wavBuffer, samples=true) { |
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super.fromBuffer(wavBuffer, samples); |
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this.bitDepthFromFmt_(); |
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this.updateDataType_(); |
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} |
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/** |
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* Return a byte buffer representig the WaveFileCreator object as a .wav file. |
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* The return value of this method can be written straight to disk. |
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* @return {!Uint8Array} A wav file. |
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* @throws {Error} If bit depth is invalid. |
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* @throws {Error} If the number of channels is invalid. |
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* @throws {Error} If the sample rate is invalid. |
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*/ |
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toBuffer() { |
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this.validateWavHeader_(); |
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return super.toBuffer(); |
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} |
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/** |
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* Set up the WaveFileCreator object based on the arguments passed. |
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* Existing chunks are reset. |
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* @param {number} numChannels The number of channels |
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* (Integer numbers: 1 for mono, 2 stereo and so on). |
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* @param {number} sampleRate The sample rate. |
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* Integer numbers like 8000, 44100, 48000, 96000, 192000. |
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* @param {string} bitDepthCode The audio bit depth code. |
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* One of '4', '8', '8a', '8m', '16', '24', '32', '32f', '64' |
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* or any value between '8' and '32' (like '12'). |
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* @param {!Array<number>|!Array<!Array<number>>|!TypedArray} samples |
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* The samples. Must be in the correct range according to the bit depth. |
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* @param {?Object} options Optional. Used to force the container |
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* as RIFX with {'container': 'RIFX'} |
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* @throws {Error} If any argument does not meet the criteria. |
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*/ |
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fromScratch(numChannels, sampleRate, bitDepthCode, samples, options={}) { |
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// reset all chunks |
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this.clearHeaders(); |
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this.newWavFile_(numChannels, sampleRate, bitDepthCode, samples, options); |
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} |
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/** |
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* Set up the WaveFileCreator object based on the arguments passed. |
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* @param {number} numChannels The number of channels |
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* (Integer numbers: 1 for mono, 2 stereo and so on). |
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* @param {number} sampleRate The sample rate. |
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* Integer numbers like 8000, 44100, 48000, 96000, 192000. |
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* @param {string} bitDepthCode The audio bit depth code. |
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* One of '4', '8', '8a', '8m', '16', '24', '32', '32f', '64' |
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* or any value between '8' and '32' (like '12'). |
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* @param {!Array<number>|!Array<!Array<number>>|!TypedArray} samples |
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* The samples. Must be in the correct range according to the bit depth. |
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* @param {?Object} options Optional. Used to force the container |
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* as RIFX with {'container': 'RIFX'} |
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* @throws {Error} If any argument does not meet the criteria. |
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* @private |
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*/ |
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newWavFile_(numChannels, sampleRate, bitDepthCode, samples, options={}) { |
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if (!options.container) { |
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options.container = 'RIFF'; |
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} |
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this.container = options.container; |
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this.bitDepth = bitDepthCode; |
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samples = interleave(samples); |
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this.updateDataType_(); |
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/** @type {number} */ |
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let numBytes = this.dataType.bits / 8; |
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this.data.samples = new Uint8Array(samples.length * numBytes); |
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packArrayTo(samples, this.dataType, this.data.samples); |
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this.makeWavHeader_( |
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bitDepthCode, numChannels, sampleRate, |
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numBytes, this.data.samples.length, options); |
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this.data.chunkId = 'data'; |
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this.data.chunkSize = this.data.samples.length; |
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this.validateWavHeader_(); |
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} |
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/** |
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* Define the header of a wav file. |
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* @param {string} bitDepthCode The audio bit depth |
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* @param {number} numChannels The number of channels |
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* @param {number} sampleRate The sample rate. |
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* @param {number} numBytes The number of bytes each sample use. |
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* @param {number} samplesLength The length of the samples in bytes. |
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* @param {!Object} options The extra options, like container defintion. |
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* @private |
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*/ |
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makeWavHeader_( |
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bitDepthCode, numChannels, sampleRate, numBytes, samplesLength, options) { |
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if (bitDepthCode == '4') { |
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this.createADPCMHeader_( |
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bitDepthCode, numChannels, sampleRate, numBytes, samplesLength, options); |
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} else if (bitDepthCode == '8a' || bitDepthCode == '8m') { |
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this.createALawMulawHeader_( |
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bitDepthCode, numChannels, sampleRate, numBytes, samplesLength, options); |
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} else if(Object.keys(this.WAV_AUDIO_FORMATS).indexOf(bitDepthCode) == -1 || |
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numChannels > 2) { |
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this.createExtensibleHeader_( |
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bitDepthCode, numChannels, sampleRate, numBytes, samplesLength, options); |
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} else { |
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this.createPCMHeader_( |
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bitDepthCode, numChannels, sampleRate, numBytes, samplesLength, options); |
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} |
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} |
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/** |
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* Create the header of a linear PCM wave file. |
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* @param {string} bitDepthCode The audio bit depth |
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* @param {number} numChannels The number of channels |
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* @param {number} sampleRate The sample rate. |
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* @param {number} numBytes The number of bytes each sample use. |
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* @param {number} samplesLength The length of the samples in bytes. |
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* @param {!Object} options The extra options, like container defintion. |
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* @private |
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*/ |
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createPCMHeader_( |
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bitDepthCode, numChannels, sampleRate, numBytes, samplesLength, options) { |
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this.container = options.container; |
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this.chunkSize = 36 + samplesLength; |
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this.format = 'WAVE'; |
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this.bitDepth = bitDepthCode; |
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this.fmt = { |
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chunkId: 'fmt ', |
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chunkSize: 16, |
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audioFormat: this.WAV_AUDIO_FORMATS[bitDepthCode] || 65534, |
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numChannels: numChannels, |
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sampleRate: sampleRate, |
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byteRate: (numChannels * numBytes) * sampleRate, |
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blockAlign: numChannels * numBytes, |
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bitsPerSample: parseInt(bitDepthCode, 10), |
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cbSize: 0, |
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validBitsPerSample: 0, |
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dwChannelMask: 0, |
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subformat: [] |
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}; |
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} |
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/** |
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* Create the header of a ADPCM wave file. |
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* @param {string} bitDepthCode The audio bit depth |
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* @param {number} numChannels The number of channels |
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* @param {number} sampleRate The sample rate. |
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* @param {number} numBytes The number of bytes each sample use. |
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* @param {number} samplesLength The length of the samples in bytes. |
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* @param {!Object} options The extra options, like container defintion. |
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* @private |
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*/ |
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createADPCMHeader_( |
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bitDepthCode, numChannels, sampleRate, numBytes, samplesLength, options) { |
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this.createPCMHeader_( |
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bitDepthCode, numChannels, sampleRate, numBytes, samplesLength, options); |
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this.chunkSize = 40 + samplesLength; |
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this.fmt.chunkSize = 20; |
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this.fmt.byteRate = 4055; |
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this.fmt.blockAlign = 256; |
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this.fmt.bitsPerSample = 4; |
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this.fmt.cbSize = 2; |
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this.fmt.validBitsPerSample = 505; |
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this.fact = { |
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chunkId: 'fact', |
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chunkSize: 4, |
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dwSampleLength: samplesLength * 2 |
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}; |
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} |
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/** |
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* Create the header of WAVE_FORMAT_EXTENSIBLE file. |
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* @param {string} bitDepthCode The audio bit depth |
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* @param {number} numChannels The number of channels |
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* @param {number} sampleRate The sample rate. |
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* @param {number} numBytes The number of bytes each sample use. |
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* @param {number} samplesLength The length of the samples in bytes. |
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* @param {!Object} options The extra options, like container defintion. |
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* @private |
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*/ |
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createExtensibleHeader_( |
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bitDepthCode, numChannels, sampleRate, numBytes, samplesLength, options) { |
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this.createPCMHeader_( |
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bitDepthCode, numChannels, sampleRate, numBytes, samplesLength, options); |
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this.chunkSize = 36 + 24 + samplesLength; |
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this.fmt.chunkSize = 40; |
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this.fmt.bitsPerSample = ((parseInt(bitDepthCode, 10) - 1) | 7) + 1; |
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this.fmt.cbSize = 22; |
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this.fmt.validBitsPerSample = parseInt(bitDepthCode, 10); |
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this.fmt.dwChannelMask = dwChannelMask(numChannels); |
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// subformat 128-bit GUID as 4 32-bit values |
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// only supports uncompressed integer PCM samples |
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this.fmt.subformat = [1, 1048576, 2852126848, 1905997824]; |
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} |
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/** |
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* Create the header of mu-Law and A-Law wave files. |
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* @param {string} bitDepthCode The audio bit depth |
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* @param {number} numChannels The number of channels |
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* @param {number} sampleRate The sample rate. |
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* @param {number} numBytes The number of bytes each sample use. |
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* @param {number} samplesLength The length of the samples in bytes. |
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* @param {!Object} options The extra options, like container defintion. |
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* @private |
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*/ |
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createALawMulawHeader_( |
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bitDepthCode, numChannels, sampleRate, numBytes, samplesLength, options) { |
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this.createPCMHeader_( |
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bitDepthCode, numChannels, sampleRate, numBytes, samplesLength, options); |
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this.chunkSize = 40 + samplesLength; |
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this.fmt.chunkSize = 20; |
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this.fmt.cbSize = 2; |
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this.fmt.validBitsPerSample = 8; |
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this.fact = { |
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chunkId: 'fact', |
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chunkSize: 4, |
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dwSampleLength: samplesLength |
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}; |
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} |
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/** |
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* Set the string code of the bit depth based on the 'fmt ' chunk. |
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* @private |
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*/ |
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bitDepthFromFmt_() { |
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if (this.fmt.audioFormat === 3 && this.fmt.bitsPerSample === 32) { |
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this.bitDepth = '32f'; |
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} else if (this.fmt.audioFormat === 6) { |
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this.bitDepth = '8a'; |
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} else if (this.fmt.audioFormat === 7) { |
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this.bitDepth = '8m'; |
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} else { |
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this.bitDepth = '' + this.fmt.bitsPerSample; |
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} |
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} |
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/** |
341
|
|
|
* Validate the bit depth. |
342
|
|
|
* @return {boolean} True is the bit depth is valid. |
343
|
|
|
* @throws {Error} If bit depth is invalid. |
344
|
|
|
* @private |
345
|
|
|
*/ |
346
|
|
|
validateBitDepth_() { |
347
|
|
|
if (!this.WAV_AUDIO_FORMATS[this.bitDepth]) { |
348
|
|
|
if (parseInt(this.bitDepth, 10) > 8 && |
349
|
|
|
parseInt(this.bitDepth, 10) < 54) { |
350
|
|
|
return true; |
351
|
|
|
} |
352
|
|
|
throw new Error('Invalid bit depth.'); |
353
|
|
|
} |
354
|
|
|
return true; |
355
|
|
|
} |
356
|
|
|
|
357
|
|
|
/** |
358
|
|
|
* Update the type definition used to read and write the samples. |
359
|
|
|
* @private |
360
|
|
|
*/ |
361
|
|
|
updateDataType_() { |
362
|
|
|
this.dataType = { |
363
|
|
|
bits: ((parseInt(this.bitDepth, 10) - 1) | 7) + 1, |
364
|
|
|
fp: this.bitDepth == '32f' || this.bitDepth == '64', |
365
|
|
|
signed: this.bitDepth != '8', |
366
|
|
|
be: this.container == 'RIFX' |
367
|
|
|
}; |
368
|
|
|
if (['4', '8a', '8m'].indexOf(this.bitDepth) > -1 ) { |
369
|
|
|
this.dataType.bits = 8; |
370
|
|
|
this.dataType.signed = false; |
371
|
|
|
} |
372
|
|
|
} |
373
|
|
|
|
374
|
|
|
/** |
375
|
|
|
* Validate the header of the file. |
376
|
|
|
* @throws {Error} If bit depth is invalid. |
377
|
|
|
* @throws {Error} If the number of channels is invalid. |
378
|
|
|
* @throws {Error} If the sample rate is invalid. |
379
|
|
|
* @ignore |
380
|
|
|
* @private |
381
|
|
|
*/ |
382
|
|
|
validateWavHeader_() { |
383
|
|
|
this.validateBitDepth_(); |
384
|
|
|
if (!validateNumChannels(this.fmt.numChannels, this.fmt.bitsPerSample)) { |
385
|
|
|
throw new Error('Invalid number of channels.'); |
386
|
|
|
} |
387
|
|
|
if (!validateSampleRate( |
388
|
|
|
this.fmt.numChannels, this.fmt.bitsPerSample, this.fmt.sampleRate)) { |
389
|
|
|
throw new Error('Invalid sample rate.'); |
390
|
|
|
} |
391
|
|
|
} |
392
|
|
|
} |
393
|
|
|
|
394
|
|
|
/** |
395
|
|
|
* Interleave de-interleaved samples. |
396
|
|
|
* @param {!Array<number>|!Array<!Array<number>>|!TypedArray} samples |
397
|
|
|
* The samples. |
398
|
|
|
* @return {!Array<number>|!Array<!Array<number>>|!TypedArray} |
399
|
|
|
* @private |
400
|
|
|
*/ |
401
|
|
|
function interleave(samples) { |
402
|
|
|
if (samples.length > 0) { |
403
|
|
|
if (samples[0].constructor === Array) { |
404
|
|
|
/** @type {!Array<number>} */ |
405
|
|
|
let finalSamples = []; |
406
|
|
|
for (let i = 0, len = samples[0].length; i < len; i++) { |
407
|
|
|
for (let j = 0, subLen = samples.length; j < subLen; j++) { |
408
|
|
|
finalSamples.push(samples[j][i]); |
409
|
|
|
} |
410
|
|
|
} |
411
|
|
|
samples = finalSamples; |
412
|
|
|
} |
413
|
|
|
} |
414
|
|
|
return samples; |
415
|
|
|
} |
416
|
|
|
|
417
|
|
|
/** |
418
|
|
|
* Return the value for dwChannelMask according to the number of channels. |
419
|
|
|
* @param {number} numChannels the number of channels. |
420
|
|
|
* @return {number} the dwChannelMask value. |
421
|
|
|
* @private |
422
|
|
|
*/ |
423
|
|
|
function dwChannelMask(numChannels) { |
424
|
|
|
/** @type {number} */ |
425
|
|
|
let mask = 0; |
426
|
|
|
// mono = FC |
427
|
|
|
if (numChannels === 1) { |
428
|
|
|
mask = 0x4; |
429
|
|
|
// stereo = FL, FR |
430
|
|
|
} else if (numChannels === 2) { |
431
|
|
|
mask = 0x3; |
432
|
|
|
// quad = FL, FR, BL, BR |
433
|
|
|
} else if (numChannels === 4) { |
434
|
|
|
mask = 0x33; |
435
|
|
|
// 5.1 = FL, FR, FC, LF, BL, BR |
436
|
|
|
} else if (numChannels === 6) { |
437
|
|
|
mask = 0x3F; |
438
|
|
|
// 7.1 = FL, FR, FC, LF, BL, BR, SL, SR |
439
|
|
|
} else if (numChannels === 8) { |
440
|
|
|
mask = 0x63F; |
441
|
|
|
} |
442
|
|
|
return mask; |
443
|
|
|
} |
444
|
|
|
|
445
|
|
|
/** |
446
|
|
|
* Validate the number of channels in a wav file according to the |
447
|
|
|
* bit depth of the audio. |
448
|
|
|
* @param {number} channels The number of channels in the file. |
449
|
|
|
* @param {number} bits The number of bits per sample. |
450
|
|
|
* @return {boolean} True is the number of channels is valid. |
451
|
|
|
* @private |
452
|
|
|
*/ |
453
|
|
|
function validateNumChannels(channels, bits) { |
454
|
|
|
/** @type {number} */ |
455
|
|
|
let blockAlign = channels * bits / 8; |
456
|
|
|
if (channels < 1 || blockAlign > 65535) { |
457
|
|
|
return false; |
458
|
|
|
} |
459
|
|
|
return true; |
460
|
|
|
} |
461
|
|
|
|
462
|
|
|
/** |
463
|
|
|
* Validate the sample rate value of a wav file according to the number of |
464
|
|
|
* channels and the bit depth of the audio. |
465
|
|
|
* @param {number} channels The number of channels in the file. |
466
|
|
|
* @param {number} bits The number of bits per sample. |
467
|
|
|
* @param {number} sampleRate The sample rate to be validated. |
468
|
|
|
* @return {boolean} True is the sample rate is valid, false otherwise. |
469
|
|
|
* @private |
470
|
|
|
*/ |
471
|
|
|
function validateSampleRate(channels, bits, sampleRate) { |
472
|
|
|
/** @type {number} */ |
473
|
|
|
let byteRate = channels * (bits / 8) * sampleRate; |
474
|
|
|
if (sampleRate < 1 || byteRate > 4294967295) { |
475
|
|
|
return false; |
476
|
|
|
} |
477
|
|
|
return true; |
478
|
|
|
} |
479
|
|
|
|