| <!DOCTYPE html> |
| <title>Test setValueAtTime with start time not on a block boundary</title> |
| <script src="/resources/testharness.js"></script> |
| <script src="/resources/testharnessreport.js"></script> |
| <script> |
| promise_test(function() { |
| const bufferSize = 200; |
| const offset = 65; |
| const sampleRate = 48000; |
| const scheduledValue = -2.0; |
| |
| var context = new OfflineAudioContext(1, bufferSize, sampleRate); |
| |
| var gain = context.createGain(); |
| gain.gain.setValueAtTime(scheduledValue, offset/sampleRate); |
| gain.connect(context.destination); |
| |
| // Apply unit DC signal to gain node. |
| var source = context.createBufferSource(); |
| source.buffer = |
| function() { |
| var buffer = context.createBuffer(1, 1, context.sampleRate); |
| buffer.getChannelData(0)[0] = 1.0; |
| return buffer; |
| }(); |
| source.loop = true; |
| source.start(); |
| source.connect(gain); |
| |
| return context.startRendering(). |
| then(function(buffer) { |
| assert_equals(buffer.length, bufferSize, "output buffer length"); |
| var output = buffer.getChannelData(0); |
| var i = 0; |
| for (; i < offset; ++i) { |
| // "Its default value is 1." |
| assert_equals(output[i], 1.0, "default gain at sample " + i); |
| } |
| for (; i < buffer.length; ++i) { |
| // "If there are no more events after this SetValue event, then for |
| // t≥T0, v(t)=V, where T0 is the startTime parameter and V is the |
| // value parameter." |
| assert_equals(output[i], scheduledValue, |
| "scheduled value at sample " + i); |
| } |
| }); |
| }); |
| </script> |