third_party/WebKit/LayoutTests/webaudio/audiochannelsplitter.html

   1 <!DOCTYPE html>
   2
   3 <!--
   4 Tests that AudioChannelSplitter works correctly.
   5 -->
   6
   7 <html>
   8 <head>
   9 <script src="../resources/js-test.js"></script>
  10 <script src="resources/compatibility.js"></script>
  11 <script type="text/javascript" src="resources/audio-testing.js"></script>
  12 </head>
  13
  14 <body>
  15
  16 <div id="description"></div>
  17 <div id="console"></div>
  18
  19 <script>
  20 description("Tests AudioChannelSplitter.");
  21
  22 var sampleRate = 44100.0;
  23 var lengthInSampleFrames = 512;
  24
  25 var context = 0;
  26 var sourceBuffer;
  27 var sourceNode;
  28 var channelSplitter;
  29 var channelMerger;
  30
  31 function createStereoBufferWithDCOffset(length, sampleRate, offset) {
  32     var buffer = context.createBuffer(2, length, sampleRate);
  33     var n = buffer.length;
  34     var channelL = buffer.getChannelData(0);
  35     var channelR = buffer.getChannelData(1);
  36
  37     for (var i = 0; i < n; ++i) {
  38         channelL[i] = offset;
  39         channelR[i] = -1.0 * offset;
  40     }
  41
  42     return buffer;
  43 }
  44
  45 // checkResult() checks that the rendered buffer is stereo and that the left channel is all -1 and right channel all +1.
  46 // In other words, we've reversed the order of the two channels.
  47 function checkResult(event) {
  48     var buffer = event.renderedBuffer;
  49
  50     var success = true;
  51
  52     if (buffer.numberOfChannels == 2) {
  53         var bufferDataL = buffer.getChannelData(0);
  54         var bufferDataR = buffer.getChannelData(1);
  55
  56         // Go through every sample and make sure it's all -1 for the left-channel, and all +1 for the right-channel.
  57         for (var i = 0; i < buffer.length; ++i) {
  58             if (bufferDataL[i] != -1 || bufferDataR[i] != 1) {
  59                 success = false;
  60                 break;
  61             }
  62         }
  63     } else {
  64         success = false;
  65     }
  66
  67     if (success) {
  68         testPassed("Correctly exchanged left and right channels.");
  69     } else {
  70         testFailed("Error on exchanging left and right channels.");
  71     }
  72
  73     finishJSTest();
  74 }
  75
  76 function runTest() {
  77     if (window.testRunner) {
  78         testRunner.dumpAsText();
  79         testRunner.waitUntilDone();
  80     }
  81
  82     window.jsTestIsAsync = true;
  83
  84     // Create stereo offline audio context.
  85     context = new OfflineAudioContext(2, lengthInSampleFrames, sampleRate);
  86
  87     try {
  88         var splitternode = context.createChannelSplitter(0);
  89         testFailed("Exception should be thrown for numberOfOutputs <= 0.");
  90     } catch(e) {
  91         testPassed("Exception been thrown for numberOfOutputs <= 0.");
  92     }
  93
  94     try {
  95         var splitternode = context.createChannelSplitter(33);
  96         testFailed("Exception should be thrown for numerOfOutputs >= 32.");
  97     } catch(e) {
  98         testPassed("Exception been thrown for numberOfOutputs >= 32.");
  99     }
 100
 101     try {
 102         var splitternode = context.createChannelSplitter(32);
 103         testPassed("AudioChannelSplitter created successfully with numberOfOutputs = 32.");
 104         if (splitternode.numberOfOutputs === 32)
 105             testPassed("AudioChannelSplitter has 32 outputs when it is created with numberOfOutputs = 32.");
 106         else
 107             testFailed("AudioChannelSplitter should have 32 outputs when it is created with numberOfOutputs = 32.");
 108
 109         if (splitternode.numberOfInputs === 1)
 110             testPassed("AudioChannelSplitter has one input.");
 111         else
 112             testFailed("AudioChannelSplitter should have one input.");
 113     } catch(e) {
 114         testFailed("Failed to create AudioChannelSplitter with numberOfInputs = 32.");
 115     }
 116
 117     try {
 118         var splitternode = context.createChannelSplitter();
 119         testPassed("AudioChannelSplitter created successfully with empty parameter.");
 120         if (splitternode.numberOfOutputs === 6)
 121             testPassed("AudioChannelSplitter has 6 outputs when it is created with empty parameter.");
 122         else
 123             testFailed("AudioChannelSplitter should have 6 outputs when it is created with empty parameter.");
 124
 125         if (splitternode.toString().indexOf("ChannelSplitterNode") > -1)
 126             testPassed("ChannelSplitterNode Object is available.");
 127         else
 128             testFailed("ChannelSplitterNode Object is not available.");
 129     } catch(e) {
 130         testFailed("Failed to create AudioChannelSplitter with empty parameter.");
 131     }
 132
 133     // Create a stereo buffer, with all +1 values in left channel, all -1 in right channel.
 134     sourceBuffer = createStereoBufferWithDCOffset(lengthInSampleFrames, sampleRate, 1);
 135
 136     sourceNode = context.createBufferSource();
 137     sourceNode.buffer = sourceBuffer;
 138
 139     // Create a channel splitter and connect it so that it split the stereo stream into two mono streams.
 140     channelSplitter = context.createChannelSplitter(2);
 141     sourceNode.connect(channelSplitter);
 142
 143     // Create a channel merger to merge the output of channel splitter.
 144     channelMerger = context.createChannelMerger();
 145     channelMerger.connect(context.destination);
 146
 147     // When merging, exchange channel layout: left->right, right->left
 148     channelSplitter.connect(channelMerger, 0, 1);
 149     channelSplitter.connect(channelMerger, 1, 0);
 150
 151     sourceNode.start(0);
 152
 153     context.oncomplete = checkResult;
 154     context.startRendering();
 155 }
 156
 157 runTest();
 158
 159 </script>
 160
 161 </body>
 162 </html>