From 1de54385650e5ccb25d76f2f9553ca33e05ad411 Mon Sep 17 00:00:00 2001 From: Trek H Date: Tue, 24 Sep 2019 17:15:58 +0930 Subject: [PATCH] audio-player: corrected indentation and comments --- cmd/audio-player/adpcm.js | 148 ++++++++++++++++----------------- cmd/audio-player/index.html | 2 +- cmd/audio-player/main.js | 120 +++++++++++++------------- cmd/audio-player/pcm-to-wav.js | 12 +-- 4 files changed, 142 insertions(+), 140 deletions(-) diff --git a/cmd/audio-player/adpcm.js b/cmd/audio-player/adpcm.js index d87e4d70..c3424944 100644 --- a/cmd/audio-player/adpcm.js +++ b/cmd/audio-player/adpcm.js @@ -29,24 +29,24 @@ LICENSE // Table of index changes (see spec). const indexTable = [ - -1, -1, -1, -1, 2, 4, 6, 8, - -1, -1, -1, -1, 2, 4, 6, 8 + -1, -1, -1, -1, 2, 4, 6, 8, + -1, -1, -1, -1, 2, 4, 6, 8 ]; // Quantize step size table (see spec). const stepTable = [ - 7, 8, 9, 10, 11, 12, 13, 14, - 16, 17, 19, 21, 23, 25, 28, 31, - 34, 37, 41, 45, 50, 55, 60, 66, - 73, 80, 88, 97, 107, 118, 130, 143, - 157, 173, 190, 209, 230, 253, 279, 307, - 337, 371, 408, 449, 494, 544, 598, 658, - 724, 796, 876, 963, 1060, 1166, 1282, 1411, - 1552, 1707, 1878, 2066, 2272, 2499, 2749, 3024, - 3327, 3660, 4026, 4428, 4871, 5358, 5894, 6484, - 7132, 7845, 8630, 9493, 10442, 11487, 12635, 13899, - 15289, 16818, 18500, 20350, 22385, 24623, 27086, 29794, - 32767 + 7, 8, 9, 10, 11, 12, 13, 14, + 16, 17, 19, 21, 23, 25, 28, 31, + 34, 37, 41, 45, 50, 55, 60, 66, + 73, 80, 88, 97, 107, 118, 130, 143, + 157, 173, 190, 209, 230, 253, 279, 307, + 337, 371, 408, 449, 494, 544, 598, 658, + 724, 796, 876, 963, 1060, 1166, 1282, 1411, + 1552, 1707, 1878, 2066, 2272, 2499, 2749, 3024, + 3327, 3660, 4026, 4428, 4871, 5358, 5894, 6484, + 7132, 7845, 8630, 9493, 10442, 11487, 12635, 13899, + 15289, 16818, 18500, 20350, 22385, 24623, 27086, 29794, + 32767 ]; const byteDepth = 2; // We are working with 16-bit samples. TODO(Trek): make configurable. @@ -59,89 +59,89 @@ let step = 0; // decodeSample takes 4 bits which represents a single ADPCM nibble, and returns a 16 bit decoded PCM sample. function decodeSample(nibble) { - let diff = 0; - if ((nibble & 4) != 0) { - diff += step; - } - if ((nibble & 2) != 0) { - diff += step >> 1; - } - if ((nibble & 1) != 0) { - diff += step >> 2; - } - diff += step >> 3; + let diff = 0; + if ((nibble & 4) != 0) { + diff += step; + } + if ((nibble & 2) != 0) { + diff += step >> 1; + } + if ((nibble & 1) != 0) { + diff += step >> 2; + } + diff += step >> 3; - if ((nibble & 8) != 0) { - diff = -diff; - } - est += diff; - idx += indexTable[nibble]; + if ((nibble & 8) != 0) { + diff = -diff; + } + est += diff; + idx += indexTable[nibble]; - if (idx < 0) { - idx = 0; - } else if (idx > stepTable.length - 1) { - idx = stepTable.length - 1; - } + if (idx < 0) { + idx = 0; + } else if (idx > stepTable.length - 1) { + idx = stepTable.length - 1; + } - step = stepTable[idx]; + step = stepTable[idx]; - result = est; - return result; + result = est; + return result; } // decode takes an array of bytes of arbitrary length representing adpcm and decodes it into pcm. function decode(b) { - // Iterate over each chunk and decode it. - let chunkLen; - var result = []; - for (var off = 0; off + headSize <= b.length; off += chunkLen) { - // Read length of chunk and check if whole chunk exists. - chunkLen = bytesToInt32(b.slice(off, off + chunkLenSize)) - if (off + chunkLen > b.length) { - break; - } + // Iterate over each chunk and decode it. + let chunkLen; + var result = []; + for (var off = 0; off + headSize <= b.length; off += chunkLen) { + // Read length of chunk and check if whole chunk exists. + chunkLen = bytesToInt32(b.slice(off, off + chunkLenSize)) + if (off + chunkLen > b.length) { + break; + } - // Initialize Decoder with first 4 bytes of b. - est = bytesToInt16(b.slice(off + chunkLenSize, off + chunkLenSize + byteDepth)); - idx = b[off + chunkLenSize + byteDepth]; - step = stepTable[idx]; + // Initialize Decoder with first 4 bytes of b. + est = bytesToInt16(b.slice(off + chunkLenSize, off + chunkLenSize + byteDepth)); + idx = b[off + chunkLenSize + byteDepth]; + step = stepTable[idx]; - result.push(...b.slice(off + chunkLenSize, off + chunkLenSize + byteDepth)); + result.push(...b.slice(off + chunkLenSize, off + chunkLenSize + byteDepth)); - for (var i = off + headSize; i < off + chunkLen - b[off + chunkLenSize + 3]; i++) { - var twoNibs = b[i]; - var nib2 = twoNibs >> 4; - var nib1 = (nib2 << 4) ^ twoNibs; + for (var i = off + headSize; i < off + chunkLen - b[off + chunkLenSize + 3]; i++) { + var twoNibs = b[i]; + var nib2 = twoNibs >> 4; + var nib1 = (nib2 << 4) ^ twoNibs; - var sample1 = int16ToBytes(decodeSample(nib1)); - result.push(...sample1); + var sample1 = int16ToBytes(decodeSample(nib1)); + result.push(...sample1); - var sample2 = int16ToBytes(decodeSample(nib2)); - result.push(...sample2); - } - if (b[off + chunkLenSize + 3] == 1) { - var padNib = b[off + chunkLen - 1]; - var sample = int16ToBytes(decodeSample(padNib)); - result.push(...sample); - } - } - return result; + var sample2 = int16ToBytes(decodeSample(nib2)); + result.push(...sample2); + } + if (b[off + chunkLenSize + 3] == 1) { + var padNib = b[off + chunkLen - 1]; + var sample = int16ToBytes(decodeSample(padNib)); + result.push(...sample); + } + } + return result; } // int16ToBytes takes a number assumed to be an int 16 and converts it to an array containing bytes (Little Endian). function int16ToBytes(num) { - return [(num & 0x00ff), (num & 0xff00) >> 8]; + return [(num & 0x00ff), (num & 0xff00) >> 8]; } // bytesToInt16 takes an array of bytes (assumed to be values between 0 and 255), interprates them as little endian and converts it to an int16. function bytesToInt16(b) { - return (b[0] | (b[1] << 8)); + return (b[0] | (b[1] << 8)); } // bytesToInt32 takes an array of bytes (assumed to be values between 0 and 255), interprates them as little endian and converts it to an int32. function bytesToInt32(b) { - return (b[0] | - (b[1] << 8) | - (b[2] << 16) | - (b[3] << 24)); + return (b[0] | + (b[1] << 8) | + (b[2] << 16) | + (b[3] << 24)); } \ No newline at end of file diff --git a/cmd/audio-player/index.html b/cmd/audio-player/index.html index c7d7ab04..55b39f02 100644 --- a/cmd/audio-player/index.html +++ b/cmd/audio-player/index.html @@ -23,7 +23,7 @@
- +
diff --git a/cmd/audio-player/main.js b/cmd/audio-player/main.js index 436ce5db..d15eaccb 100644 --- a/cmd/audio-player/main.js +++ b/cmd/audio-player/main.js @@ -23,82 +23,84 @@ LICENSE If not, see [GNU licenses](http://www.gnu.org/licenses). */ -function processData() { - const input = event.target.files[0] - const reader = new FileReader() +// playFile will process and play the chosen target file. +function playFile() { + const input = event.target.files[0] + const reader = new FileReader() - reader.onload = event => { - bytes = new Uint8Array(event.target.result) + reader.onload = event => { + bytes = new Uint8Array(event.target.result) - // decode adpcm to pcm - var decoded = decode(Array.from(bytes)) + // Decode adpcm to pcm. + var decoded = decode(Array.from(bytes)) - // convert raw pcm to wav TODO(Trek): make these configurable. - var wav = pcmToWav(decoded, 48000, 1, 16); + // Convert raw pcm to wav TODO(Trek): make these configurable. + var wav = pcmToWav(decoded, 48000, 1, 16); - // play wav data in player - const blob = new Blob([Uint8Array.from(wav)], { - type: 'audio/wav' - }); - const url = URL.createObjectURL(blob); + // Play wav data in player. + const blob = new Blob([Uint8Array.from(wav)], { + type: 'audio/wav' + }); + const url = URL.createObjectURL(blob); - const audio = document.getElementById('audio'); - const source = document.getElementById('source'); + const audio = document.getElementById('audio'); + const source = document.getElementById('source'); - source.src = url; - audio.load(); - audio.play(); - } - reader.onerror = error => reject(error) - reader.readAsArrayBuffer(input) + source.src = url; + audio.load(); + audio.play(); + } + reader.onerror = error => reject(error) + reader.readAsArrayBuffer(input) } // getQuery gets everything after the question mark in the URL. function getQuery() { - var regex = new RegExp("\\?(.*)"); - var match = regex.exec(window.location.href); - if (match == null) { - return ''; - } else { - return decodeURIComponent(match[1].replace(/\+/g, " ")); - } + var regex = new RegExp("\\?(.*)"); + var match = regex.exec(window.location.href); + if (match == null) { + return ''; + } else { + return decodeURIComponent(match[1].replace(/\+/g, " ")); + } } +// load gets the file from the given url and displays a link for download. function load() { - var url = document.getElementById('url').value; - if (url == "") { - url = getQuery() - document.getElementById('url').value = url; - } - if (url[0] == '/') { - url = window.location.protocol + '//' + window.location.host + url; - } - if (url == "") { - return; - } + var url = document.getElementById('url').value; + if (url == "") { + url = getQuery() + document.getElementById('url').value = url; + } + if (url[0] == '/') { + url = window.location.protocol + '//' + window.location.host + url; + } + if (url == "") { + return; + } - var request = new XMLHttpRequest(); - request.responseType = "blob"; - request.onreadystatechange = function () { - if (request.readyState === XMLHttpRequest.DONE) { - if (request.status === 200) { - console.log("request received"); + var request = new XMLHttpRequest(); + request.responseType = "blob"; + request.onreadystatechange = function () { + if (request.readyState === XMLHttpRequest.DONE) { + if (request.status === 200) { + console.log("request received"); - data = request.response; + data = request.response; - dataURL = URL.createObjectURL(data); + dataURL = URL.createObjectURL(data); - var link = document.getElementById("link"); - link.href = dataURL; - link.download = "media.ts"; - link.innerHTML = "Download"; + var link = document.getElementById("link"); + link.href = dataURL; + link.download = "media.ts"; + link.innerHTML = "Download"; - } else { - console.log('There was a problem with the request. Status: ' + request.status); - } - } - } - request.open("GET", url, true); - request.send(); + } else { + console.log('There was a problem with the request. Status: ' + request.status); + } + } + } + request.open("GET", url, true); + request.send(); } \ No newline at end of file diff --git a/cmd/audio-player/pcm-to-wav.js b/cmd/audio-player/pcm-to-wav.js index a9f368ca..f0e44506 100644 --- a/cmd/audio-player/pcm-to-wav.js +++ b/cmd/audio-player/pcm-to-wav.js @@ -24,24 +24,24 @@ LICENSE // pcmToWav takes raw pcm data along with the sample rate, number of channels and bit-depth, // and adds a WAV header to it so that it can be read and played by common players. -// input and output data bytes are represented as arrays of 8 bit integers. +// Input and output data bytes are represented as arrays of 8 bit integers. // WAV spec.: http://soundfile.sapp.org/doc/WaveFormat/ function pcmToWav(data, rate, channels, bitdepth) { - subChunk2ID = [100, 97, 116, 97]; // "data" + subChunk2ID = [100, 97, 116, 97]; // "data". subChunk2Size = int32ToBytes(data.length); - subChunk1ID = [102, 109, 116, 32]; // "fmt " + subChunk1ID = [102, 109, 116, 32]; // "fmt ". subChunk1Size = int32ToBytes(16); - audioFmt = int16ToBytes(1); // 1 = PCM + audioFmt = int16ToBytes(1); // 1 = PCM. numChannels = int16ToBytes(channels); sampleRate = int32ToBytes(rate); byteRate = int32ToBytes(rate * channels * bitdepth / 8); blockAlign = int16ToBytes(channels * bitdepth / 8); bitsPerSample = int16ToBytes(bitdepth) - chunkID = [82, 73, 70, 70]; // "RIFF" + chunkID = [82, 73, 70, 70]; // "RIFF". chunkSize = int32ToBytes(36 + data.length); - format = [87, 65, 86, 69]; // "WAVE" + format = [87, 65, 86, 69]; // "WAVE". result = chunkID; result.push(...chunkSize, ...format, ...subChunk1ID, ...subChunk1Size, ...audioFmt, ...numChannels, ...sampleRate, ...byteRate, ...blockAlign, ...bitsPerSample, ...subChunk2ID, ...subChunk2Size);