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Issue 1803233002:
AnalyserNode should downmix channels to mono. (Closed)
Base URL: https://chromium.googlesource.com/chromium/src.git@master| OLD | NEW |
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| (Empty) | |
| 1 <!doctype html> | |
| 2 <html> | |
| 3 <head> | |
| 4 <script src="../resources/js-test.js"></script> | |
| 5 <script src="resources/compatibility.js"></script> | |
| 6 <script src="resources/audio-testing.js"></script> | |
| 7 <script src="resources/fft.js"></script> | |
| 8 <script src="resources/realtimeanalyser-testing.js"></script> | |
| 9 <title>Test AnalyserNode Downmixing</title> | |
| 10 </head> | |
| 11 | |
| 12 <body> | |
| 13 <script> | |
| 14 description("Test AnalyserNode Downmixing"); | |
| 15 window.jsTestIsAsync = true; | |
| 16 | |
| 17 var sampleRate = 44100; | |
| 18 var renderFrames = 2048; | |
| 19 | |
| 20 var audit = Audit.createTaskRunner(); | |
| 21 | |
| 22 var testConfigs = [{ | |
| 23 channelCount: 1, | |
| 24 message: "mono", | |
| 25 floatRelError: 6.3283e-8 | |
| 26 }, { | |
| 27 channelCount: 2, | |
| 28 message: "stereo", | |
| 29 floatRelError: 1.1681e-7 | |
| 30 }, { | |
| 31 channelCount: 4, | |
| 32 message: "quad", | |
| 33 floatRelError: 4.9793e-7 | |
| 34 }, { | |
| 35 channelCount: 6, | |
| 36 message: "5.1", | |
| 37 floatRelError: 2.0215e-7 | |
| 38 }, { | |
| 39 channelCount: 3, | |
| 40 message: "3-channel", | |
| 41 floatRelError: 6.3283e-8 | |
| 42 }]; | |
| 43 | |
| 44 // Create tasks for each entry in testConfigs | |
| 45 for (k in testConfigs) { | |
| 46 audit.defineTask(testConfigs[k].message, (function (config) { | |
| 47 return function(done) { | |
| 48 runTest(config).then(done); | |
| 49 }; | |
| 50 })(testConfigs[k])); | |
| 51 } | |
| 52 | |
| 53 audit.defineTask("finish", function (done) { | |
| 54 finishJSTest(); | |
| 55 done(); | |
| 56 }); | |
| 57 | |
| 58 audit.runTasks(); | |
| 59 | |
| 60 // Test downmixing of the AnalyserNode time data. We use the downmixing t hat automatically | |
| 61 // happens in the destination node to generate the reference data which is compared to the | |
| 62 // data that the Analyser node has captured. | |
| 63 function runTest(options) { | |
| 64 // Context MUST have exactly one channel so that we downmix the source t o mono to generate | |
| 65 // the reference. | |
| 66 var context = new OfflineAudioContext(1, renderFrames, sampleRate); | |
| 67 | |
| 68 var channels = options.channelCount || 1; | |
| 69 var source = context.createBufferSource(); | |
| 70 | |
| 71 // The signals in each channel. Doesn't matter much what is in here, but it's best if the | |
| 72 // values aren't linearly increasing so that the average of the values i sn't one of the | |
| 73 // values (in case the implementation does something silly). Only need to support up to 6 | |
| 74 // channels. | |
| 75 var bufferValues = [1, 2, 3, 4, 5, 6].map(function (x) { | |
| 76 return x * x | |
| 77 });; | |
| 78 source.buffer = createConstantBuffer(context, renderFrames, bufferValues .slice(0, channels)); | |
| 79 | |
| 80 var analyser = context.createAnalyser(); | |
| 81 analyser.smoothingTimeConstant = 0; | |
| 82 analyser.fftSize = 256; | |
| 83 | |
| 84 // Run analyser as an automatic pull node. Do NOT connect to the destina tion. | |
|
hongchan
2016/03/16 21:51:42
Why running as an automatic pull mode does matter?
Raymond Toy
2016/03/16 21:58:23
Because the source is also connected to the destin
Raymond Toy
2016/03/18 17:33:04
More comments added.
| |
| 85 source.connect(analyser); | |
| 86 source.connect(context.destination); | |
| 87 | |
| 88 var timeData = new Float32Array(analyser.fftSize); | |
| 89 var freqData = new Float32Array(analyser.frequencyBinCount); | |
| 90 | |
| 91 var suspendFrame = analyser.fftSize; | |
| 92 context.suspend(suspendFrame / context.sampleRate).then(function () { | |
| 93 analyser.getFloatTimeDomainData(timeData); | |
| 94 analyser.getFloatFrequencyData(freqData); | |
| 95 }).then(context.resume.bind(context)); | |
| 96 | |
| 97 source.start(); | |
| 98 return context.startRendering().then(function (renderedBuffer) { | |
| 99 var success = true; | |
| 100 | |
| 101 // Verify the time domain data is correct. | |
| 102 var prefix = "Analyser downmix " + options.message + " to mono" | |
| 103 success = Should(prefix + " time data", timeData, { | |
| 104 verbose: true | |
| 105 }) | |
| 106 .beEqualToArray(renderedBuffer.getChannelData(0).subarray(0, analyse r.fftSize)); | |
| 107 | |
| 108 var expectedTimeData = renderedBuffer.getChannelData(0).subarray(0, an alyser.fftSize); | |
| 109 var fftOrder = Math.floor(Math.log2(analyser.fftSize)); | |
| 110 var expectedFreqData = computeFFTMagnitude(expectedTimeData, fftOrder) .map(linearToDb); | |
| 111 | |
| 112 success = compareFloatFreq(prefix + " freq data", freqData, expectedFr eqData, { | |
| 113 precision: 6, | |
| 114 floatRelError: options.floatRelError, | |
| 115 }) && success; | |
| 116 | |
| 117 if (success) | |
| 118 testPassed(prefix + " downmixed correctly.\n"); | |
| 119 else | |
| 120 testFailed(prefix + " not downmixed correctly.\n"); | |
| 121 }); | |
| 122 } | |
| 123 </script> | |
| 124 </body> | |
| 125 </html> | |
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