test_channelSplitterNodeWithVolume.html (2383B)
1 <!DOCTYPE HTML> 2 <html> 3 <head> 4 <title>Test ChannelSplitterNode</title> 5 <script src="/tests/SimpleTest/SimpleTest.js"></script> 6 <script type="text/javascript" src="webaudio.js"></script> 7 <link rel="stylesheet" type="text/css" href="/tests/SimpleTest/test.css" /> 8 </head> 9 <body> 10 <pre id="test"> 11 <script class="testbody" type="text/javascript"> 12 13 // We do not use our generic graph test framework here because 14 // the splitter node is special in that it creates multiple 15 // output ports. 16 17 SimpleTest.waitForExplicitFinish(); 18 addLoadEvent(function() { 19 var context = new AudioContext(); 20 var buffer = context.createBuffer(4, 2048, context.sampleRate); 21 var expectedBuffer = context.createBuffer(4, 2048, context.sampleRate); 22 for (var j = 0; j < 4; ++j) { 23 for (var i = 0; i < 2048; ++i) { 24 buffer.getChannelData(j)[i] = Math.sin(440 * 2 * (j + 1) * Math.PI * i / context.sampleRate); 25 expectedBuffer.getChannelData(j)[i] = buffer.getChannelData(j)[i] / 2; 26 } 27 } 28 var emptyBuffer = context.createBuffer(1, 2048, context.sampleRate); 29 30 var destination = context.destination; 31 32 var source = context.createBufferSource(); 33 34 var splitter = context.createChannelSplitter(); 35 is(splitter.channelCount, 6, "splitter node has 2 input channels by default"); 36 is(splitter.channelCountMode, "explicit", "Correct channelCountMode for the splitter node"); 37 is(splitter.channelInterpretation, "discrete", "Correct channelCountInterpretation for the splitter node"); 38 39 source.buffer = buffer; 40 var gain = context.createGain(); 41 gain.gain.value = 0.5; 42 source.connect(gain); 43 gain.connect(splitter); 44 45 var channelsSeen = 0; 46 function createHandler(i) { 47 return function(e) { 48 is(e.inputBuffer.numberOfChannels, 1, "Correct input channel count"); 49 if (i < 4) { 50 compareBuffers(e.inputBuffer.getChannelData(0), expectedBuffer.getChannelData(i)); 51 } else { 52 compareBuffers(e.inputBuffer.getChannelData(0), emptyBuffer.getChannelData(0)); 53 } 54 e.target.onaudioprocess = null; 55 ++channelsSeen; 56 57 if (channelsSeen == 6) { 58 SimpleTest.finish(); 59 } 60 }; 61 } 62 63 for (var i = 0; i < 6; ++i) { 64 var sp = context.createScriptProcessor(2048, 1); 65 splitter.connect(sp, i); 66 sp.onaudioprocess = createHandler(i); 67 sp.connect(destination); 68 } 69 70 source.start(0); 71 }); 72 73 </script> 74 </pre> 75 </body> 76 </html>