| <!doctype html> |
| <html> |
| <head> |
| <title>Test WaveShaper Copies Curve Data</title> |
| <script src="../resources/testharness.js"></script> |
| <script src="../resources/testharnessreport.js"></script> |
| <script src="resources/audio-testing.js"></script> |
| </head> |
| |
| <body> |
| <script> |
| // Sample rate and number of frames are fairly arbitrary. We need to |
| // render, however, at least 384 frames. 1024 is a nice small value. |
| var sampleRate = 16000; |
| var renderFrames = 1024; |
| |
| var audit = Audit.createTaskRunner(); |
| |
| audit.defineTask("test copying", function (taskDone) { |
| // Two-channel context; channel 0 contains the test data and channel 1 |
| // contains the expected result. Channel 1 has the normal WaveShaper |
| // output and channel 0 has the WaveShaper output with a modified curve. |
| var context = new OfflineAudioContext(2, renderFrames, sampleRate); |
| |
| // Just use a default oscillator as the source. Doesn't really matter |
| // what we use. |
| var src = context.createOscillator(); |
| src.type = "sawtooth"; |
| |
| // Create the wave shapers: ws0 is the test shaper, and ws1 is the |
| // reference wave shaper. |
| var ws0 = context.createWaveShaper(); |
| var ws1 = context.createWaveShaper(); |
| |
| // Wave shaper curves. Doesn't really matter what we use as long as it |
| // modifies the input in some way. Thus, keep it simple and just invert |
| // the input. |
| var desiredCurve = [1, 0, -1]; |
| var curve0 = Float32Array.from(desiredCurve); |
| var curve1 = Float32Array.from(desiredCurve); |
| |
| ws0.curve = curve0; |
| ws1.curve = curve1; |
| |
| var merger = context.createChannelMerger(2); |
| |
| // Connect the graph |
| src.connect(ws0); |
| src.connect(ws1); |
| |
| ws0.connect(merger, 0, 0); |
| ws1.connect(merger, 0, 1); |
| |
| merger.connect(context.destination); |
| |
| // Let the context run for a bit and then modify the curve for ws0. |
| // Doesn't really matter what we modify the curve to as long as it's |
| // different. |
| context.suspend(256 / context.sampleRate) |
| .then(function () { |
| curve0[0] = -0.5; |
| curve0[1] = 0.125; |
| curve0[2] = 0.75; |
| }) |
| .then(context.resume.bind(context)); |
| |
| src.start(); |
| |
| context.startRendering().then(function (renderedBuffer) { |
| var actual = renderedBuffer.getChannelData(0); |
| var expected = renderedBuffer.getChannelData(1); |
| |
| // Modifying the wave shaper curve should not modify the output so the |
| // outputs from the two wave shaper nodes should be exactly identical. |
| var success = Should("WaveShaper with modified curve", actual) |
| .beEqualToArray(expected); |
| |
| Should("Summary: ", success).summarize( |
| "Output correctly did not change with modified WaveShaper curve.", |
| "Output incorrectly changed due to modified WaveShaper curve."); |
| }).then(taskDone); |
| }); |
| |
| audit.runTasks(); |
| </script> |
| </body> |
| </html> |
