| <!doctype html> |
| <html> |
| <head> |
| <script src="../resources/js-test.js"></script> |
| <script src="resources/compatibility.js"></script> |
| <script src="resources/audio-testing.js"></script> |
| </head> |
| |
| <body> |
| <script> |
| description('Test synchronous graph manipulation with OfflineAudioContext.suspend() and OfflineAudioContext.resume().'); |
| window.jsTestIsAsync = true; |
| |
| var context; |
| var renderQuantum = 128; |
| var renderDuration = 3; |
| |
| // The sample rate is multiple of the rendering quantum, so suspension |
| // times fall in to the render quantum boundary. |
| var sampleRate = renderQuantum * 100; |
| |
| context = new OfflineAudioContext(1, sampleRate * renderDuration, sampleRate); |
| |
| // Create a constant buffer of 1.0. |
| var constantBuffer = createConstantBuffer(context, 1, 1.0); |
| var constantSource = context.createBufferSource(); |
| constantSource.buffer = constantBuffer; |
| constantSource.loop = true; |
| |
| // The audio output from the beginning (0.0 second) to the first suspend |
| // time should be 0.0 because there is no connection to the destination. |
| |
| // Suspend at 1 second and activate the source node. The audio output |
| // should be 1.0 from |suspendTime1| to the next suspension. |
| var suspendTime1 = 1; |
| context.suspend(suspendTime1).then(function () { |
| if (context.currentTime === suspendTime1) |
| testPassed('Context is suspended at ' + suspendTime1 * sampleRate + ' frame as expected.'); |
| |
| constantSource.connect(context.destination); |
| constantSource.start(); |
| testPassed('A constant buffer is connected to destination and started at ' + |
| suspendTime1 * sampleRate + ' frame.'); |
| |
| context.resume(); |
| }); |
| |
| // Suspend at 2 seconds and disconnect the node. The audio output should |
| // be 0.0 from |suspendTime2| to the end. |
| var suspendTime2 = 2; |
| context.suspend(suspendTime2).then(function () { |
| if (context.currentTime === suspendTime2) |
| testPassed('Context is suspended at ' + suspendTime2 * sampleRate + ' frame as expected.'); |
| |
| constantSource.disconnect(); |
| testPassed('A constant buffer is disconnected at ' + suspendTime2 * sampleRate + ' frame.'); |
| |
| context.resume(); |
| }); |
| |
| context.startRendering().then(function (buffer) { |
| verifyResult(buffer); |
| finishJSTest(); |
| }); |
| |
| function verifyResult(buffer) { |
| var data = buffer.getChannelData(0); |
| |
| var suspendIndex1 = suspendTime1 * sampleRate; |
| var suspendIndex2 = suspendTime2 * sampleRate; |
| var endIndex = renderDuration * sampleRate; |
| |
| // Split the rendered buffer into 3 segments: |
| // [0, suspendIndex1), [suspendIndex1, suspendIndex2), [suspendIndex2, |
| // endIndex). |
| var subarray0 = data.subarray(0, suspendIndex1); |
| var subarray1 = data.subarray(suspendIndex1, suspendIndex2); |
| var subarray2 = data.subarray(suspendIndex2, endIndex); |
| |
| // Each segment should contain a constant value of 0, 1 and 0 |
| // respectively. |
| Should('Buffer frame [0, ' + suspendIndex1 + ')', subarray0).beConstantValueOf(0); |
| Should('Buffer frame [' + suspendIndex1 + ', ' + suspendIndex2 + ')', subarray1) |
| .beConstantValueOf(1); |
| Should('Buffer frame [' + suspendIndex2 + ', ' + endIndex + ')', subarray2) |
| .beConstantValueOf(0); |
| } |
| |
| successfullyParsed = true; |
| </script> |
| |
| </body> |
| </html> |
