| <!DOCTYPE html> |
| <html> |
| <head> |
| <title> |
| mediaelementaudiosourcenode-playbackrate.html |
| </title> |
| <script src="../../imported/w3c/web-platform-tests/resources/testharness.js"></script> |
| <script src="../../resources/testharnessreport.js"></script> |
| <script src="../resources/audit-util.js"></script> |
| <script src="../resources/audit.js"></script> |
| </head> |
| <body> |
| <script id="layout-test-code"> |
| let audit = Audit.createTaskRunner(); |
| |
| function waitFor(element, type) { |
| return new Promise(resolve => { |
| element.addEventListener(type, resolve, { once: true }); |
| }); |
| } |
| |
| function sleepFor(time) { |
| return new Promise(resolve => setTimeout(resolve, time)); |
| } |
| |
| audit.define( |
| { |
| label: 'mediaelementsourcenode-playbackrate', |
| description: 'Verify playbackRate at 2.0 generates correctly pitched audio' |
| }, |
| async (task, should) => { |
| window.audioElement = new Audio('../resources/media/half-a-second-48000.mp3'); |
| audioElement.playbackRate = 2; |
| audioElement.preservesPitch = false; |
| audioElement.loop = true; |
| |
| let context = new AudioContext({sampleRate: 48000}); |
| let mediaSource = context.createMediaElementSource(audioElement); |
| let analyser = context.createAnalyser(); |
| let gain = context.createGain(); |
| |
| analyser.fftSize = 2048; |
| analyser.smoothingTimeConstant = 0; |
| analyser.minDecibels = -40; |
| let frequencyData = new Uint8Array(analyser.frequencyBinCount); |
| |
| // Silence test output |
| gain.gain.value = 0; |
| |
| mediaSource.connect(analyser); |
| analyser.connect(gain); |
| gain.connect(context.destination); |
| |
| await context.resume(); |
| await audioElement.play(); |
| |
| while (!audioElement.paused) { |
| analyser.getByteFrequencyData(frequencyData); |
| if (frequencyData[13] == 0 && frequencyData[26] > 0) |
| break; |
| await sleepFor(10); |
| } |
| |
| should(frequencyData[13] == 0, 'frequencyData[305hz] == 0').beTrue(); |
| should(frequencyData[26] > 0, 'frequencyData[610hz] > 0').beTrue(); |
| |
| audioElement.pause(); |
| context.suspend(); |
| task.done(); |
| }); |
| audit.run(); |
| </script> |
| </body> |
| </html> |
