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Push — master ( 29aa6e...c898d2 )
by Rafael S.
02:29
created

interleave.js ➔ deInterleave   A

Complexity

Conditions 4

Size

Total Lines 14
Code Lines 9

Duplication

Lines 0
Ratio 0 %

Importance

Changes 0
Metric Value
eloc 9
dl 0
loc 14
rs 9.95
c 0
b 0
f 0
cc 4
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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 interleave function.
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 * @see https://github.com/rochars/wavefile
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 */
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/**
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 * Interleave de-interleaved samples.
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 * @param {!Array<number>|!Array<!Array<number>>|!TypedArray} samples
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 *    The samples.
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 * @return {!Array<number>|!Array<!Array<number>>|!TypedArray}
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 */
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export function interleave(samples) {
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  if (samples.length > 0) {
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    if (samples[0].constructor === Array) {
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      /** @type {!Array<number>} */
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      let finalSamples = [];
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      for (let i = 0, len = samples[0].length; i < len; i++) {
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        for (let j = 0, subLen = samples.length; j < subLen; j++) {
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          finalSamples.push(samples[j][i]);
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        }
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      }
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      samples = finalSamples;
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    }
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  }
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  return samples;
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}
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/**
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 * De-interleave samples into multiple channels.
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 * @param {!Float64Array|Array<Float64Array>} samples The samples.
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 * @param {number} numChannels The number of channels to split the samples.
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 * @return {!Array<Float64Array>}
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 */
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export function deInterleave(samples, numChannels) {
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  /** @type {!Array<Float64Array>} */
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  let finalSamples = [];
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  for (let i = 0; i < numChannels; i++) {
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    finalSamples[i] = new Float64Array(samples.length / numChannels);
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  }
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  for (let i = 0; i < numChannels; i ++) {
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    let s = 0;
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    for (let j = i; j < samples.length; j+= numChannels) {
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      finalSamples[i][s++] = samples[j];
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    }
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  }
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  return finalSamples;
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}
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