From 9805506cf29a5739b7530b3a91ad647d5a639230 Mon Sep 17 00:00:00 2001 From: Trek H Date: Sat, 14 Sep 2019 20:28:59 +0930 Subject: [PATCH 1/8] audio-player: changed syntax --- cmd/audio-player/adpcm.js | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/cmd/audio-player/adpcm.js b/cmd/audio-player/adpcm.js index 958a295c..d87e4d70 100644 --- a/cmd/audio-player/adpcm.js +++ b/cmd/audio-player/adpcm.js @@ -49,13 +49,13 @@ const stepTable = [ 32767 ]; -const byteDepth = 2, // We are working with 16-bit samples. TODO(Trek): make configurable. - headSize = 8, // Number of bytes in the header of ADPCM. - chunkLenSize = 4; +const byteDepth = 2; // We are working with 16-bit samples. TODO(Trek): make configurable. +const headSize = 8; // Number of bytes in the header of ADPCM. +const chunkLenSize = 4; -let est = 0, // Estimation of sample based on quantised ADPCM nibble. - idx = 0, // Index to step used for estimation. - step = 0; +let est = 0; // Estimation of sample based on quantised ADPCM nibble. +let idx = 0; // Index to step used for estimation. +let step = 0; // decodeSample takes 4 bits which represents a single ADPCM nibble, and returns a 16 bit decoded PCM sample. function decodeSample(nibble) { From 64febc479b0d57180aaa8f6861b349f69f95536b Mon Sep 17 00:00:00 2001 From: Trek H Date: Sat, 14 Sep 2019 22:21:52 +0930 Subject: [PATCH 2/8] audio-player: log request status on error --- cmd/audio-player/main.js | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/cmd/audio-player/main.js b/cmd/audio-player/main.js index 3606a653..436ce5db 100644 --- a/cmd/audio-player/main.js +++ b/cmd/audio-player/main.js @@ -95,7 +95,7 @@ function load() { link.innerHTML = "Download"; } else { - console.log('There was a problem with the request.'); + console.log('There was a problem with the request. Status: ' + request.status); } } } From 7ed73f3301191e20fbbdd51c1299e420de22dc4c Mon Sep 17 00:00:00 2001 From: Trek H Date: Sat, 14 Sep 2019 22:35:37 +0930 Subject: [PATCH 3/8] audio-player: fixed conflict --- cmd/audio-player/adpcm.js | 147 +++++++++++++++++++++++++++++++++ cmd/audio-player/favicon.ico | Bin 0 -> 15406 bytes cmd/audio-player/index.html | 44 ++++++++++ cmd/audio-player/main.js | 104 +++++++++++++++++++++++ cmd/audio-player/pcm-to-wav.js | 64 ++++++++++++++ 5 files changed, 359 insertions(+) create mode 100644 cmd/audio-player/adpcm.js create mode 100644 cmd/audio-player/favicon.ico create mode 100644 cmd/audio-player/index.html create mode 100644 cmd/audio-player/main.js create mode 100644 cmd/audio-player/pcm-to-wav.js diff --git a/cmd/audio-player/adpcm.js b/cmd/audio-player/adpcm.js new file mode 100644 index 00000000..d87e4d70 --- /dev/null +++ b/cmd/audio-player/adpcm.js @@ -0,0 +1,147 @@ +/* +NAME + adpcm.js + +AUTHOR + Trek Hopton + +LICENSE + This file is Copyright (C) 2018 the Australian Ocean Lab (AusOcean) + + It is free software: you can redistribute it and/or modify them + under the terms of the GNU General Public License as published by the + Free Software Foundation, either version 3 of the License, or (at your + option) any later version. + + It is distributed in the hope that it will be useful, but WITHOUT + ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License + for more details. + + You should have received a copy of the GNU General Public License in gpl.txt. + If not, see [GNU licenses](http://www.gnu.org/licenses). +*/ + +/* + Original IMA/DVI ADPCM specification: (http://www.cs.columbia.edu/~hgs/audio/dvi/IMA_ADPCM.pdf). + Reference algorithms for ADPCM compression and decompression are in part 6. +*/ + +// Table of index changes (see spec). +const indexTable = [ + -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 +]; + +const byteDepth = 2; // We are working with 16-bit samples. TODO(Trek): make configurable. +const headSize = 8; // Number of bytes in the header of ADPCM. +const chunkLenSize = 4; + +let est = 0; // Estimation of sample based on quantised ADPCM nibble. +let idx = 0; // Index to step used for estimation. +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; + + 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; + } + + step = stepTable[idx]; + + 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; + } + + // 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)); + + 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 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]; +} + +// 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)); +} + +// 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)); +} \ No newline at end of file diff --git a/cmd/audio-player/favicon.ico b/cmd/audio-player/favicon.ico new file mode 100644 index 0000000000000000000000000000000000000000..465b02c257d3a5388ce1a7744355834fbd37fa82 GIT binary patch literal 15406 zcmeHO32>9w5f(`rkPoo2&0#KI_`sKBUAAobKJh78zp*UIwk+SqMihrYN+u3zVIXPK z5E?oyB?U5cI-zMMkf8xmAS6Ii8X%;!C8VSrA($)J@olu-C+n7sEL)b%6wU1Xzx4m_ z?f3TW+ugVOM59fiJxTNMpyAbzR{s=@#--6{ettvWLp^D<9rzoAp?w}qqn+@f(L(VZ zY=SL@e#gtOA4yJVQi)*B-V(mo1xe!U%MT+eZss{j(!3p&`H_SLtuiM(U&L|iDTpZWS99@AZ$On5m%1_JWHS zV&Kkg4ieXbZnv{x*RO)GkExn|gltzRV!42b<9?a&-n=#t)aobz7@n?Q4MS{nc)npC zoIA|`Wv-XL{maiSerQ|L@BQy1;BTKq!r)*u3=Bj;b)J3gjj>Hc`_7I?lra+?JczQu zzj*mP%psSJZC3!{=HLO9f;{h=Oen`nk#6FGWBbR5os%i?;6?x2c zva|)iSLQD{Sd+ix=vb&c)BoLytdMOD(u}6njlwV@7b{q%D5*GZS$e=BA;+yt7(=&P z?lxqsM%yqTj`MC;(K#D^>GgFq@1cGSlxKzQ(_vVp z6fIgNnENI6HSWCicoBm%J!Eroa`IDE1&p>L7JX3v%uatX+IHetuiLE+#Zi(J|Ffg* zV=V1Z9|r465?f0Iz5`?FXDn^yX$#-f`7T{QLKYqEsVgjtcSCZwgWNRjh`-hKW$Rjz z8+OpZe=1OM9LE?oMz04dQ95@0(X?0h2}ZS@SqFyxaTh5_T6qsGs-ycCIk zf@#y|82e1)d*bW+`l8|2n?tP1fcTN(*qQogC2ymdGThEvBwK^$wC z2O^J+tE1rTX)ZjY^s~+%{oL^n6K%#DIzA7(o;w`?C2@41V%^|{mc?-9GZysrFoF2n zwRMZeo&WhWLGY7$e;f}Rx_)5kWlG`zXYlXrWI|^LThCV~D`)Z7@iV_Z=I@;OHNO@U% zkH~xXwg}t@80Z?mA|eze_m?`|~w^#B(t zvwieDjQy+m{gD4N_0wXWD@ar3f-K$NZjz?X0Wr^IM7#+WNy>sFx;%k7HfMZS zNeyUs1}{qo<%MYjiRYnD#0Dr6!C_s;R13;Kg) zf;pF!MXaK>Hrf+9{^UwgOP+3&q~=#-1s^C8%)jqQS>U)Hpsro5E@Ez3(NGYA?4}s= z{(rtFc@j*~(khWgnkT_mH6Jo(t5=u$)|Frx#N%Nb0YHMqM zw6causuprSB6%(??qO|}wtuHS$9(D_=0vVGE=ycvHijpfWm(Z!SNIF&XL~hcc2cg$ zPC2MC_8Kfr@cl-S&#jYZMrm}3_?oIb#%7!&;_D_#S4KLQ8hxVTXPqT}stwn4i!75b zNm+EB=$W1J7%5MOzbC@=pva4UU8Sn@XcWh<7joQ*Uz_Z*H^>2HElUqL)l`umuE=Md zB)R=ZMfO^pYOKZGuA>sNIPYjlPy5ZowbFGCJ|@GkewYTKI1j7Xp6d4 z6&ag`@}Z`Cts$Ny-|Ggll<7z_kUShjGoUO9>uIrA6CH!h&`-A`MSpUr(ruQYYxZc`ad#Tu^*tZR&b zbAL~S&Q2B#V7_KxfZH|kU z;A!&RBRdpv@Xg#hhYUj9e!LMhV^c)!)0!a zU3cH#7Xb&~TL@)|2Hha_it60i@Y?!dICeM@Zr@_V_xBj^+J*?MJ(!Gh82n2RKhHV% z`y=4cz6BcmBrhgQ@q`U)m~i442kza)HK)y$c6LS~{_shO|M2?@p(fuOo^J|-gZntp z{#~3!j(4)+9~g*)bDu}T{=Gc-&sS{d>1Jrodzjmd$%=ny4Ktt*YlGyRiaBoGI+?8a zb@*&uALDnt53?n68UIlH=7O=A8?;D#;SW1_aPgm9 z97hb+c87GzKKxFOpSAHP*}n+cSbI$LfHgIX;hjAk`1-4OO-$6$G4l9RB@0HK&4jZPySFUFvS0wabPShN%DkM6+!Uc+dPctS?~+o$JmVjQ3i?}Up%+W z#u z+w$_v--u&7zZAsm#uC2sLN9Puhz@blUI~yHWu?d?;!q1ss1t`P4)XgRh1jitjJj+&j>k+ z|L>Ww^V)XKy;{WcxT`GStZQqlb!n@ub*T}>HsiVX8;`&okpD~c;@SKIN+CZ2i`bg; zBG1)|<~GVww&Qc3X=}Z37DeG7J0E`@OTd8=_#Y2!$T$E1 literal 0 HcmV?d00001 diff --git a/cmd/audio-player/index.html b/cmd/audio-player/index.html new file mode 100644 index 00000000..c7d7ab04 --- /dev/null +++ b/cmd/audio-player/index.html @@ -0,0 +1,44 @@ + + + + + + Audio Player + + + + + + + +
+
+
+ URL: +
+
+ +
+
+
+
+
+ +
+
+
+ +
+
+
+
+
+ ©2019 Australian Ocean Laboratory Limited (AusOcean) (License) +
+
+ + + \ No newline at end of file diff --git a/cmd/audio-player/main.js b/cmd/audio-player/main.js new file mode 100644 index 00000000..436ce5db --- /dev/null +++ b/cmd/audio-player/main.js @@ -0,0 +1,104 @@ +/* +NAME + main.js + +AUTHOR + Trek Hopton + Alan Noble + +LICENSE + This file is Copyright (C) 2018 the Australian Ocean Lab (AusOcean) + + It is free software: you can redistribute it and/or modify them + under the terms of the GNU General Public License as published by the + Free Software Foundation, either version 3 of the License, or (at your + option) any later version. + + It is distributed in the hope that it will be useful, but WITHOUT + ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License + for more details. + + You should have received a copy of the GNU General Public License in gpl.txt. + If not, see [GNU licenses](http://www.gnu.org/licenses). +*/ + +function processData() { + const input = event.target.files[0] + const reader = new FileReader() + + reader.onload = event => { + bytes = new Uint8Array(event.target.result) + + // 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); + + // 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'); + + 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, " ")); + } +} + +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 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; + + dataURL = URL.createObjectURL(data); + + 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(); +} \ No newline at end of file diff --git a/cmd/audio-player/pcm-to-wav.js b/cmd/audio-player/pcm-to-wav.js new file mode 100644 index 00000000..a9f368ca --- /dev/null +++ b/cmd/audio-player/pcm-to-wav.js @@ -0,0 +1,64 @@ +/* +NAME + pcm-to-wav.js + +AUTHOR + Trek Hopton + +LICENSE + This file is Copyright (C) 2018 the Australian Ocean Lab (AusOcean) + + It is free software: you can redistribute it and/or modify them + under the terms of the GNU General Public License as published by the + Free Software Foundation, either version 3 of the License, or (at your + option) any later version. + + It is distributed in the hope that it will be useful, but WITHOUT + ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License + for more details. + + You should have received a copy of the GNU General Public License in gpl.txt. + If not, see [GNU licenses](http://www.gnu.org/licenses). +*/ + +// 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. +// WAV spec.: http://soundfile.sapp.org/doc/WaveFormat/ +function pcmToWav(data, rate, channels, bitdepth) { + subChunk2ID = [100, 97, 116, 97]; // "data" + subChunk2Size = int32ToBytes(data.length); + + subChunk1ID = [102, 109, 116, 32]; // "fmt " + subChunk1Size = int32ToBytes(16); + 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" + chunkSize = int32ToBytes(36 + data.length); + format = [87, 65, 86, 69]; // "WAVE" + + result = chunkID; + result.push(...chunkSize, ...format, ...subChunk1ID, ...subChunk1Size, ...audioFmt, ...numChannels, ...sampleRate, ...byteRate, ...blockAlign, ...bitsPerSample, ...subChunk2ID, ...subChunk2Size); + return result.concat(data); +} + +// int32ToBytes takes a number assumed to be an int 32 and converts it to an array containing bytes (Little Endian). +function int32ToBytes(num) { + return [ + (num & 0x000000ff), + (num & 0x0000ff00) >> 8, + (num & 0x00ff0000) >> 16, + (num & 0xff000000) >> 24 + ]; +} + +// 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]; +} \ No newline at end of file From 1de54385650e5ccb25d76f2f9553ca33e05ad411 Mon Sep 17 00:00:00 2001 From: Trek H Date: Tue, 24 Sep 2019 17:15:58 +0930 Subject: [PATCH 4/8] 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); From 0517e399d1e00e923e1de89852658ba84d46565a Mon Sep 17 00:00:00 2001 From: Trek H Date: Fri, 27 Sep 2019 12:06:09 +0930 Subject: [PATCH 5/8] audio-player: using correct js declarations --- cmd/audio-player/adpcm.js | 20 ++++++++++---------- 1 file changed, 10 insertions(+), 10 deletions(-) diff --git a/cmd/audio-player/adpcm.js b/cmd/audio-player/adpcm.js index c3424944..396f2b5a 100644 --- a/cmd/audio-player/adpcm.js +++ b/cmd/audio-player/adpcm.js @@ -93,8 +93,8 @@ function decodeSample(nibble) { function decode(b) { // Iterate over each chunk and decode it. let chunkLen; - var result = []; - for (var off = 0; off + headSize <= b.length; off += chunkLen) { + let result = []; + for (let 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) { @@ -108,20 +108,20 @@ function decode(b) { 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 (let i = off + headSize; i < off + chunkLen - b[off + chunkLenSize + 3]; i++) { + let twoNibs = b[i]; + let nib2 = twoNibs >> 4; + let nib1 = (nib2 << 4) ^ twoNibs; - var sample1 = int16ToBytes(decodeSample(nib1)); + let sample1 = int16ToBytes(decodeSample(nib1)); result.push(...sample1); - var sample2 = int16ToBytes(decodeSample(nib2)); + let sample2 = int16ToBytes(decodeSample(nib2)); result.push(...sample2); } if (b[off + chunkLenSize + 3] == 1) { - var padNib = b[off + chunkLen - 1]; - var sample = int16ToBytes(decodeSample(padNib)); + let padNib = b[off + chunkLen - 1]; + let sample = int16ToBytes(decodeSample(padNib)); result.push(...sample); } } From 7f2c77368dc450cbe10977c9ecccbc276b46dc35 Mon Sep 17 00:00:00 2001 From: Trek H Date: Fri, 27 Sep 2019 15:36:25 +0930 Subject: [PATCH 6/8] audio-player: structured Decoder as a class --- cmd/audio-player/adpcm.js | 218 ++++++++++++++++++++------------------ cmd/audio-player/main.js | 16 +-- 2 files changed, 122 insertions(+), 112 deletions(-) diff --git a/cmd/audio-player/adpcm.js b/cmd/audio-player/adpcm.js index 396f2b5a..784145b7 100644 --- a/cmd/audio-player/adpcm.js +++ b/cmd/audio-player/adpcm.js @@ -27,121 +27,129 @@ LICENSE Reference algorithms for ADPCM compression and decompression are in part 6. */ -// Table of index changes (see spec). -const indexTable = [ - -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 -]; - -const byteDepth = 2; // We are working with 16-bit samples. TODO(Trek): make configurable. -const headSize = 8; // Number of bytes in the header of ADPCM. -const chunkLenSize = 4; - -let est = 0; // Estimation of sample based on quantised ADPCM nibble. -let idx = 0; // Index to step used for estimation. -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; - - 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; +class Decoder { + constructor() { + this.est = 0; // Estimation of sample based on quantised ADPCM nibble. + this.idx = 0; // Index to step used for estimation. + this.step = 0; } - step = stepTable[idx]; + // Table of index changes (see spec). + static get indexTable() { + return [ + -1, -1, -1, -1, 2, 4, 6, 8, + -1, -1, -1, -1, 2, 4, 6, 8 + ]; + } - result = est; - return result; -} + // Quantize step size table (see spec). + static get stepTable() { + return [ + 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 + ]; + } -// 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; - let result = []; - for (let 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; + static get byteDepth() { return 2; } // We are working with 16-bit samples. TODO(Trek): make configurable. + static get headSize() { return 8; } // Number of bytes in the header of ADPCM. + static get chunkLenSize() { return 4; } + + // decodeSample takes 4 bits which represents a single ADPCM nibble, and returns a 16 bit decoded PCM sample. + decodeSample(nibble) { + let diff = 0; + if ((nibble & 4) != 0) { + diff += this.step; + } + if ((nibble & 2) != 0) { + diff += this.step >> 1; + } + if ((nibble & 1) != 0) { + diff += this.step >> 2; + } + diff += this.step >> 3; + + if ((nibble & 8) != 0) { + diff = -diff; + } + this.est += diff; + this.idx += Decoder.indexTable[nibble]; + + if (this.idx < 0) { + this.idx = 0; + } else if (this.idx > Decoder.stepTable.length - 1) { + this.idx = Decoder.stepTable.length - 1; } - // 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]; + this.step = Decoder.stepTable[this.idx]; - result.push(...b.slice(off + chunkLenSize, off + chunkLenSize + byteDepth)); - - for (let i = off + headSize; i < off + chunkLen - b[off + chunkLenSize + 3]; i++) { - let twoNibs = b[i]; - let nib2 = twoNibs >> 4; - let nib1 = (nib2 << 4) ^ twoNibs; - - let sample1 = int16ToBytes(decodeSample(nib1)); - result.push(...sample1); - - let sample2 = int16ToBytes(decodeSample(nib2)); - result.push(...sample2); - } - if (b[off + chunkLenSize + 3] == 1) { - let padNib = b[off + chunkLen - 1]; - let sample = int16ToBytes(decodeSample(padNib)); - result.push(...sample); - } + return this.est; } - 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]; -} + // decode takes an array of bytes of arbitrary length representing adpcm and decodes it into pcm. + decode(b) { + // Iterate over each chunk and decode it. + let chunkLen; + let result = []; + for (let off = 0; off + Decoder.headSize <= b.length; off += chunkLen) { + // Read length of chunk and check if whole chunk exists. + chunkLen = Decoder.bytesToInt32(b.slice(off, off + Decoder.chunkLenSize)) + if (off + chunkLen > b.length) { + break; + } -// 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)); -} + // Initialize Decoder with first 4 bytes of b. + this.est = Decoder.bytesToInt16(b.slice(off + Decoder.chunkLenSize, off + Decoder.chunkLenSize + Decoder.byteDepth)); + this.idx = b[off + Decoder.chunkLenSize + Decoder.byteDepth]; + this.step = Decoder.stepTable[this.idx]; -// 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)); + result.push(...b.slice(off + Decoder.chunkLenSize, off + Decoder.chunkLenSize + Decoder.byteDepth)); + + for (let i = off + Decoder.headSize; i < off + chunkLen - b[off + Decoder.chunkLenSize + 3]; i++) { + let twoNibs = b[i]; + let nib2 = twoNibs >> 4; + let nib1 = (nib2 << 4) ^ twoNibs; + + let sample1 = Decoder.int16ToBytes(this.decodeSample(nib1)); + result.push(...sample1); + + let sample2 = Decoder.int16ToBytes(this.decodeSample(nib2)); + result.push(...sample2); + } + if (b[off + Decoder.chunkLenSize + 3] == 1) { + let padNib = b[off + chunkLen - 1]; + let sample = Decoder.int16ToBytes(this.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). + static int16ToBytes(num) { + 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. + static bytesToInt16(b) { + 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. + static bytesToInt32(b) { + return (b[0] | + (b[1] << 8) | + (b[2] << 16) | + (b[3] << 24)); + } } \ No newline at end of file diff --git a/cmd/audio-player/main.js b/cmd/audio-player/main.js index d15eaccb..7cc07077 100644 --- a/cmd/audio-player/main.js +++ b/cmd/audio-player/main.js @@ -31,11 +31,13 @@ function playFile() { reader.onload = event => { bytes = new Uint8Array(event.target.result) + let dec = new Decoder(); + // Decode adpcm to pcm. - var decoded = decode(Array.from(bytes)) + let decoded = dec.decode(Array.from(bytes)) // Convert raw pcm to wav TODO(Trek): make these configurable. - var wav = pcmToWav(decoded, 48000, 1, 16); + let wav = pcmToWav(decoded, 48000, 1, 16); // Play wav data in player. const blob = new Blob([Uint8Array.from(wav)], { @@ -57,8 +59,8 @@ function playFile() { // getQuery gets everything after the question mark in the URL. function getQuery() { - var regex = new RegExp("\\?(.*)"); - var match = regex.exec(window.location.href); + let regex = new RegExp("\\?(.*)"); + let match = regex.exec(window.location.href); if (match == null) { return ''; } else { @@ -68,7 +70,7 @@ function getQuery() { // load gets the file from the given url and displays a link for download. function load() { - var url = document.getElementById('url').value; + let url = document.getElementById('url').value; if (url == "") { url = getQuery() document.getElementById('url').value = url; @@ -80,7 +82,7 @@ function load() { return; } - var request = new XMLHttpRequest(); + let request = new XMLHttpRequest(); request.responseType = "blob"; request.onreadystatechange = function () { if (request.readyState === XMLHttpRequest.DONE) { @@ -91,7 +93,7 @@ function load() { dataURL = URL.createObjectURL(data); - var link = document.getElementById("link"); + let link = document.getElementById("link"); link.href = dataURL; link.download = "media.ts"; link.innerHTML = "Download"; From d170afea8eedbdae81cda82d4700886b07f30fbc Mon Sep 17 00:00:00 2001 From: Trek H Date: Fri, 27 Sep 2019 18:59:08 +0930 Subject: [PATCH 7/8] audio-player: added decBytes function I added a function called decBytes to calculate the number of PCM bytes that will be generated from a given array of ADPCM bytes. --- cmd/audio-player/adpcm.js | 30 +++++++++++++++++++++++++++--- 1 file changed, 27 insertions(+), 3 deletions(-) diff --git a/cmd/audio-player/adpcm.js b/cmd/audio-player/adpcm.js index 784145b7..eb11bd26 100644 --- a/cmd/audio-player/adpcm.js +++ b/cmd/audio-player/adpcm.js @@ -61,9 +61,10 @@ class Decoder { ]; } - static get byteDepth() { return 2; } // We are working with 16-bit samples. TODO(Trek): make configurable. - static get headSize() { return 8; } // Number of bytes in the header of ADPCM. - static get chunkLenSize() { return 4; } + static get byteDepth() { return 2; } // We are working with 16-bit samples. TODO(Trek): make configurable. + static get headSize() { return 8; } // Number of bytes in the header of ADPCM. + static get chunkLenSize() { return 4; } // Length in bytes of the chunk length field in header. + static get compFact() { return 4; } // In general ADPCM compresses by a factor of 4. // decodeSample takes 4 bits which represents a single ADPCM nibble, and returns a 16 bit decoded PCM sample. decodeSample(nibble) { @@ -152,4 +153,27 @@ class Decoder { (b[2] << 16) | (b[3] << 24)); } + + // decBytes takes a parameter that is assumed to be a byte array containing one or more adpcm chunks. + // It reads the chunk lengths from the chunk headers to calculate and return the number of pcm bytes that are expected to be decoded from the adpcm. + static decBytes(b){ + let chunkLen; + let n = 0; + for (let off = 0; off + Decoder.headSize <= b.length; off += chunkLen) { + chunkLen = Decoder.bytesToInt32(b.slice(off, off + Decoder.chunkLenSize)) + if (off + chunkLen > b.length) { + break; + } + + // Account for uncompressed sample in header. + n += Decoder.byteDepth; + // Account for PCM bytes that will result from decoding ADPCM. + n += (chunkLen - Decoder.headSize)*Decoder.compFact; + // Account for padding. + if(b[off+Decoder.chunkLenSize+3] == 0x01){ + n -= Decoder.byteDepth; + } + } + return n; + } } \ No newline at end of file From 76dddda6cd7e03ab6e70915ff2dbb9b5c5b9e6b0 Mon Sep 17 00:00:00 2001 From: Trek H Date: Mon, 30 Sep 2019 18:43:55 +0930 Subject: [PATCH 8/8] audio-player: using typed arrays change decoder to use typed array and array indexing instead of pushing to regular arrays for performance reasons. --- cmd/audio-player/adpcm.js | 32 +++++++------- cmd/audio-player/main.js | 8 ++-- cmd/audio-player/pcm-to-wav.js | 81 ++++++++++++++++++++++++---------- 3 files changed, 77 insertions(+), 44 deletions(-) diff --git a/cmd/audio-player/adpcm.js b/cmd/audio-player/adpcm.js index eb11bd26..0648fbaa 100644 --- a/cmd/audio-player/adpcm.js +++ b/cmd/audio-player/adpcm.js @@ -61,7 +61,7 @@ class Decoder { ]; } - static get byteDepth() { return 2; } // We are working with 16-bit samples. TODO(Trek): make configurable. + static get byteDepth() { return 2; } // We are working with 16-bit samples. static get headSize() { return 8; } // Number of bytes in the header of ADPCM. static get chunkLenSize() { return 4; } // Length in bytes of the chunk length field in header. static get compFact() { return 4; } // In general ADPCM compresses by a factor of 4. @@ -99,9 +99,10 @@ class Decoder { // decode takes an array of bytes of arbitrary length representing adpcm and decodes it into pcm. decode(b) { + let result = new Uint16Array(Decoder.decBytes(b)/Decoder.byteDepth); + let resultOff = 0; // Iterate over each chunk and decode it. let chunkLen; - let result = []; for (let off = 0; off + Decoder.headSize <= b.length; off += chunkLen) { // Read length of chunk and check if whole chunk exists. chunkLen = Decoder.bytesToInt32(b.slice(off, off + Decoder.chunkLenSize)) @@ -109,38 +110,37 @@ class Decoder { break; } - // Initialize Decoder with first 4 bytes of b. + // Initialize Decoder. this.est = Decoder.bytesToInt16(b.slice(off + Decoder.chunkLenSize, off + Decoder.chunkLenSize + Decoder.byteDepth)); this.idx = b[off + Decoder.chunkLenSize + Decoder.byteDepth]; this.step = Decoder.stepTable[this.idx]; - result.push(...b.slice(off + Decoder.chunkLenSize, off + Decoder.chunkLenSize + Decoder.byteDepth)); + result[resultOff] = Decoder.bytesToInt16(b.slice(off + Decoder.chunkLenSize, off + Decoder.chunkLenSize + Decoder.byteDepth)); + resultOff++; for (let i = off + Decoder.headSize; i < off + chunkLen - b[off + Decoder.chunkLenSize + 3]; i++) { let twoNibs = b[i]; let nib2 = twoNibs >> 4; let nib1 = (nib2 << 4) ^ twoNibs; - let sample1 = Decoder.int16ToBytes(this.decodeSample(nib1)); - result.push(...sample1); - - let sample2 = Decoder.int16ToBytes(this.decodeSample(nib2)); - result.push(...sample2); + let sample1 = this.decodeSample(nib1); + result[resultOff] = sample1; + resultOff++; + + let sample2 = this.decodeSample(nib2); + result[resultOff] = sample2; + resultOff++; } if (b[off + Decoder.chunkLenSize + 3] == 1) { let padNib = b[off + chunkLen - 1]; - let sample = Decoder.int16ToBytes(this.decodeSample(padNib)); - result.push(...sample); + let sample = this.decodeSample(padNib); + result[resultOff] = sample; + resultOff++; } } return result; } - // int16ToBytes takes a number assumed to be an int 16 and converts it to an array containing bytes (Little Endian). - static int16ToBytes(num) { - 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. static bytesToInt16(b) { return (b[0] | (b[1] << 8)); diff --git a/cmd/audio-player/main.js b/cmd/audio-player/main.js index 7cc07077..a71d1687 100644 --- a/cmd/audio-player/main.js +++ b/cmd/audio-player/main.js @@ -29,18 +29,18 @@ function playFile() { const reader = new FileReader() reader.onload = event => { - bytes = new Uint8Array(event.target.result) + bytes = new Uint8Array(event.target.result); let dec = new Decoder(); // Decode adpcm to pcm. - let decoded = dec.decode(Array.from(bytes)) + let decoded = dec.decode(bytes); // Convert raw pcm to wav TODO(Trek): make these configurable. - let wav = pcmToWav(decoded, 48000, 1, 16); + let wav = pcmToWav(new Uint8Array(decoded.buffer), 48000, 1, 16); // Play wav data in player. - const blob = new Blob([Uint8Array.from(wav)], { + const blob = new Blob([wav], { type: 'audio/wav' }); const url = URL.createObjectURL(blob); diff --git a/cmd/audio-player/pcm-to-wav.js b/cmd/audio-player/pcm-to-wav.js index f0e44506..32848abb 100644 --- a/cmd/audio-player/pcm-to-wav.js +++ b/cmd/audio-player/pcm-to-wav.js @@ -24,41 +24,74 @@ 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 should be a Uint16Array containing 16 bit PCM samples, output will be a Uint8Array representing the bytes of the wav file. // WAV spec.: http://soundfile.sapp.org/doc/WaveFormat/ function pcmToWav(data, rate, channels, bitdepth) { - subChunk2ID = [100, 97, 116, 97]; // "data". - subChunk2Size = int32ToBytes(data.length); + let subChunk2ID = [100, 97, 116, 97]; // "data". + let subChunk2Size = int32ToBytes(data.length); - subChunk1ID = [102, 109, 116, 32]; // "fmt ". - subChunk1Size = int32ToBytes(16); - 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) + let subChunk1ID = [102, 109, 116, 32]; // "fmt ". + let subChunk1Size = int32ToBytes(16); + let audioFmt = int16ToBytes(1); // 1 = PCM. + let numChannels = int16ToBytes(channels); + let sampleRate = int32ToBytes(rate); + let byteRate = int32ToBytes(rate * channels * bitdepth / 8); + let blockAlign = int16ToBytes(channels * bitdepth / 8); + let bitsPerSample = int16ToBytes(bitdepth) - chunkID = [82, 73, 70, 70]; // "RIFF". - chunkSize = int32ToBytes(36 + data.length); - format = [87, 65, 86, 69]; // "WAVE". + let chunkID = [82, 73, 70, 70]; // "RIFF". + let chunkSize = int32ToBytes(36 + data.length); + let format = [87, 65, 86, 69]; // "WAVE". - result = chunkID; - result.push(...chunkSize, ...format, ...subChunk1ID, ...subChunk1Size, ...audioFmt, ...numChannels, ...sampleRate, ...byteRate, ...blockAlign, ...bitsPerSample, ...subChunk2ID, ...subChunk2Size); - return result.concat(data); + let result = new Uint8Array((data.length*2) + 44); + let off = 0; + + result.set(chunkID, off); + off += 4; + result.set(chunkSize, off); + off += 4; + result.set(format, off); + off += 4; + result.set(subChunk1ID, off); + off += 4; + result.set(subChunk1Size, off); + off += 4; + result.set(audioFmt, off); + off += 2; + result.set(numChannels, off); + off += 2; + result.set(sampleRate, off); + off += 4; + result.set(byteRate, off); + off += 4; + result.set(blockAlign, off); + off += 2; + result.set(bitsPerSample, off); + off += 2; + result.set(subChunk2ID, off); + off += 4; + result.set(subChunk2Size, off); + off += 4; + + result.set(data, off); + + return result; } // int32ToBytes takes a number assumed to be an int 32 and converts it to an array containing bytes (Little Endian). function int32ToBytes(num) { - return [ - (num & 0x000000ff), - (num & 0x0000ff00) >> 8, - (num & 0x00ff0000) >> 16, - (num & 0xff000000) >> 24 - ]; + let b = new Uint8Array(4); + b[0] = (num & 0x000000ff); + b[1] = (num & 0x0000ff00) >> 8; + b[2] = (num & 0x00ff0000) >> 16; + b[3] = (num & 0xff000000) >> 24; + return b; } // 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]; + let b = new Uint8Array(2); + b[0] = (num & 0x00ff); + b[1] = (num & 0xff00) >> 8; + return b; } \ No newline at end of file