Mercurial > hg > webaudioevaluationtool
changeset 482:6281b02dcb58 Dev_main
Added WAVE.js, conversion of some C scripts to JS for WAVE file manipulation. By default, will use the WAVE decoder first before fallback to browser decoders. All browsers now support Integer 8-/16-/24-/34-bit and IEEE Float 32 WAVE files.
| author | Nicholas Jillings <n.g.r.jillings@se14.qmul.ac.uk> |
|---|---|
| date | Sat, 16 Jan 2016 14:51:02 +0000 |
| parents | d39c99d83891 |
| children | a275f9689af6 |
| files | WAVE.js core.js example_eval/radio_example.xml index.html |
| diffstat | 4 files changed, 192 insertions(+), 19 deletions(-) [+] |
line wrap: on
line diff
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/WAVE.js Sat Jan 16 14:51:02 2016 +0000 @@ -0,0 +1,154 @@ +// Decode and perform WAVE file byte level manipulation + +find_subarray = function(arr,subarr) { + var arr_length = arr.length; + var subarr_length = subarr.length; + var last_check_index = arr_length - subarr_length; + + positionLoop: + for (var i=0; i <= last_check_index; i++) + { + for (var j=0; j< subarr_length; j++) + { + if (arr[i + j] !== subarr[j]) { + continue positionLoop; + } + } + return i; + } + return -1; +}; + +function WAVE() +{ + // The WAVE file object + this.status == 'WAVE_DECLARED' + + this.decoded_data = null; + + this.RIFF = String(); //ChunkID + this.size; //ChunkSize + this.FT_Header; //Format + this.fmt_marker; //Subchunk1ID + this.formatDataLength; //Subchunk1Size + this.type; //AudioFormat + this.num_channels; //NumChannels + this.sample_rate; //SampleRate + this.byte_rate; //ByteRate + this.block_align; //BlockAlign + this.bits_per_sample; //BitsPerSample + this.data_header; //Subchunk2ID + this.data_size; //Subchunk2Size + this.num_samples; + + this.open = function(IOArrayBuffer) + { + var IOView8 = new Uint8Array(IOArrayBuffer); + IOView8.subarray(0,4).forEach(function(i){ + var char = String.fromCharCode(i); + this.RIFF = this.RIFF.concat(char); + },this); + if (this.RIFF != 'RIFF') + { + console.log('WAVE ERR - Not a RIFF file'); + return 1; + } + this.size = 0; + IOView8.subarray(4,8).forEach(function(i,a){this.size += Number(i)<<(8*a);},this); + this.FT_Header = String(); + IOView8.subarray(8,12).forEach(function(i){this.FT_Header = this.FT_Header.concat(String.fromCharCode(i));},this); + this.fmt_marker = String(); + IOView8.subarray(12,16).forEach(function(i){this.fmt_marker = this.fmt_marker.concat(String.fromCharCode(i));},this); + this.formatDataLength = 0; + IOView8.subarray(16,20).forEach(function(i,a){this.formatDataLength += Number(i)<<(8*a);},this); + this.type = 0; + IOView8.subarray(20,22).forEach(function(i,a){this.type += Number(i)<<(8*a);},this); + this.num_channels = 0; + IOView8.subarray(22,24).forEach(function(i,a){this.num_channels += Number(i)<<(8*a);},this); + this.sample_rate = 0; + IOView8.subarray(24,28).forEach(function(i,a){this.sample_rate += Number(i)<<(8*a);},this); + this.byte_rate = 0; + IOView8.subarray(28,32).forEach(function(i,a){this.byte_rate += Number(i)<<(8*a);},this); + this.block_align = 0; + IOView8.subarray(32,34).forEach(function(i,a){this.block_align += Number(i)<<(8*a);},this); + this.bits_per_sample = 0; + IOView8.subarray(34,36).forEach(function(i,a){this.bits_per_sample += Number(i)<<(8*a);},this); + + // Find the data header first + var data_start = find_subarray(IOView8,[100, 97, 116, 97]); + + this.data_header = String(); + IOView8.subarray(data_start,data_start+4).forEach(function(i){this.data_header = this.data_header.concat(String.fromCharCode(i));},this); + this.data_size = 0; + IOView8.subarray(data_start+4,data_start+8).forEach(function(i,a){this.data_size += Number(i)<<(8*a);},this); + + this.num_samples = this.data_size / this.block_align; + + this.decoded_data = []; + if (this.type != 1 && this.type != 3) { + console.log("Neither PCM nor IEEE float, cannot decode"); + return 1; + } + for (var c=0; c<this.num_channels; c++) + { + this.decoded_data.push(new Float32Array(this.num_samples)); + } + var sampleDataOffset = data_start+8; + + // Now need to decode the data from sampleDataOffset + // Data is always interleved + var data_view; + if (this.type == 3) + { + // Already in float + if (this.bits_per_sample == 32) { + data_view = new Float32Array(IOArrayBuffer.slice(sampleDataOffset,sampleDataOffset+this.data_size)); + } else if (this.bits_per_sample == 64) { + data_view = new Float64Array(IOArrayBuffer.slice(sampleDataOffset,sampleDataOffset+this.data_size)); + } + } else if (this.type == 1) + { + data_view = new Float32Array(this.num_samples); + integerConvert(new Uint8Array(IOArrayBuffer.slice(sampleDataOffset,sampleDataOffset+this.data_size)),data_view,this.bits_per_sample/8); + } + deInterlace(data_view,this.decoded_data); + return 0; + }; +} + +function deInterlace(src_array, dst_array) +{ + var number = src_array.length; + var channels = dst_array.length; + var channel_index = 0; + var dst_index = 0; + for (var n=0; n<number; n++) + { + dst_array[channel_index][dst_index] = src_array[n]; + channel_index++; + if (channel_index >= channels) { + channel_index = 0; + dst_index++; + } + } +} + +function integerConvert(srcView,dstView,srcBytes) +{ + //Convert integers of a Uint8Array of certain byte length into a Float32Array + var number = dstView.length; + var outBits = srcBytes*8; + var endShift = 32 - outBits; + if (srcView.length != dstView.length*srcBytes) + { + return -1; + } + for (var n=0; n<number; n++) + { + var intData; + var srcIndex = n*srcBytes; + srcView.subarray(srcIndex,srcIndex+srcBytes).forEach(function(i,a){intData += Number(i)<<(8*a);},this); + intData = (intData << (endShift)); + dstView[n] = intData / 2147483648; + } +} \ No newline at end of file
--- a/core.js Fri Jan 15 11:04:23 2016 +0000 +++ b/core.js Sat Jan 16 14:51:02 2016 +0000 @@ -991,24 +991,42 @@ // Create callback to decode the data asynchronously this.xmlRequest.onloadend = function() { - audioContext.decodeAudioData(bufferObj.xmlRequest.response, function(decodedData) { - bufferObj.buffer = decodedData; - calculateLoudness(bufferObj,"I"); - - }, function(){ - // Should only be called if there was an error, but sometimes gets called continuously - // Check here if the error is genuine - if (bufferObj.buffer == undefined) { - // Genuine error - console.log('FATAL - Error loading buffer on '+audioObj.id); - if (request.status == 404) - { - console.log('FATAL - Fragment '+audioObj.id+' 404 error'); - console.log('URL: '+audioObj.url); - errorSessionDump('Fragment '+audioObj.id+' 404 error'); - } - } - }); + // Use inbuilt WAVE decoder first + var waveObj = new WAVE(); + if (waveObj.open(bufferObj.xmlRequest.response) == 0) + { + bufferObj.buffer = audioContext.createBuffer(waveObj.num_channels,waveObj.num_samples,waveObj.sample_rate); + for (var c=0; c<waveObj.num_channels; c++) + { + var buffer_ptr = bufferObj.buffer.getChannelData(c); + for (var n=0; n<waveObj.num_samples; n++) + { + buffer_ptr[n] = waveObj.decoded_data[c][n]; + } + } + delete waveObj; + } else { + audioContext.decodeAudioData(bufferObj.xmlRequest.response, function(decodedData) { + bufferObj.buffer = decodedData; + }, function(e){ + // Should only be called if there was an error, but sometimes gets called continuously + // Check here if the error is genuine + if (bufferObj.xmlRequest.response == undefined) { + // Genuine error + console.log('FATAL - Error loading buffer on '+audioObj.id); + if (request.status == 404) + { + console.log('FATAL - Fragment '+audioObj.id+' 404 error'); + console.log('URL: '+audioObj.url); + errorSessionDump('Fragment '+audioObj.id+' 404 error'); + } + } + }); + } + if (bufferObj.buffer != undefined) + { + calculateLoudness(bufferObj,"I"); + } }; this.progress = 0; this.progressCallback = function(event){
--- a/example_eval/radio_example.xml Fri Jan 15 11:04:23 2016 +0000 +++ b/example_eval/radio_example.xml Sat Jan 16 14:51:02 2016 +0000 @@ -17,7 +17,7 @@ <interfaceoption type="show" name="page-count"/> </interface> </setup> - <page id='test-0' hostURL="example_eval/" randomiseOrder='true' repeatCount='0' loop='true' showElementComments='true' loudness="-12"> + <page id='test-0' hostURL="example_eval/" randomiseOrder='true' repeatCount='0' loop='true' showElementComments='true' loudness="-23"> <interface> <scales> <scalelabel position="0">(1) Very Annoying</scalelabel>
--- a/index.html Fri Jan 15 11:04:23 2016 +0000 +++ b/index.html Sat Jan 16 14:51:02 2016 +0000 @@ -20,6 +20,7 @@ <script src='core.js'></script> <script src='loudness.js'></script> <script src='xmllint.js'></script> + <script src='WAVE.js'></script> <script type="text/javascript"> // SEARCH QUERY: By using the GET Request option ?url=loca/path/to/project.xml in the URL bar, you can load a project quickly if (window.location.search.length != 0)