<!DOCTYPE html>
<html>
<head>
<title>
Test AudioWorkletNode's dynamic channel count feature
</title>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="/webaudio/resources/audit.js"></script>
<script src="/webaudio/resources/audit-util.js"></script>
</head>
<body>
<script id="layout-test-code">
let audit = Audit.createTaskRunner();
// Arbitrary numbers used to align the test with render quantum boundary.
let sampleRate = RENDER_QUANTUM_FRAMES * 100;
let renderLength = RENDER_QUANTUM_FRAMES * 2;
let context;
let filePath = 'processors/gain-processor.js';
let testChannelValues = [1, 2, 3];
// Creates a 3-channel buffer and play with BufferSourceNode. The source
// goes through a bypass AudioWorkletNode (gain value of 1).
audit.define('setup-buffer-and-worklet', (task, should) => {
context = new OfflineAudioContext(testChannelValues.length,
renderLength,
sampleRate);
// Explicitly sets the destination channelCountMode and
// channelInterpretation to make sure the result does no mixing.
context.channeCountMode = 'explicit';
context.channelInterpretation = 'discrete';
context.audioWorklet.addModule(filePath).then(() => {
let testBuffer = createConstantBuffer(context, 1, testChannelValues);
let sourceNode = new AudioBufferSourceNode(context);
let gainWorkletNode = new AudioWorkletNode(context, 'gain');
gainWorkletNode.parameters.get('gain').value = 1.0;
sourceNode.connect(gainWorkletNode).connect(context.destination);
// Suspend the context at 128 sample frames and play the source with
// the assigned buffer.
context.suspend(RENDER_QUANTUM_FRAMES/sampleRate).then(() => {
sourceNode.buffer = testBuffer;
sourceNode.loop = true;
sourceNode.start();
context.resume();
});
task.done();
});
});
// Verifies if the rendered buffer has all zero for the first half (before
// 128 samples) and the expected values for the second half.
audit.define('verify-rendered-buffer', (task, should) => {
context.startRendering().then(renderedBuffer => {
testChannelValues.forEach((value, index) => {
let channelData = renderedBuffer.getChannelData(index);
should(channelData.subarray(0, RENDER_QUANTUM_FRAMES),
'First half of Channel #' + index)
.beConstantValueOf(0);
should(channelData.subarray(RENDER_QUANTUM_FRAMES, renderLength),
'Second half of Channel #' + index)
.beConstantValueOf(value);
});
task.done();
});
});
audit.run();
</script>
</body>
</html>
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