| <!DOCTYPE html> |
| <html> |
| <head> |
| <meta charset="utf-8"> |
| <title>A recorded muted audio track should produce silence</title> |
| <script src="/resources/testharness.js"></script> |
| <script src="/resources/testharnessreport.js"></script> |
| </head> |
| <body> |
| <video id="video1" controls></video> |
| <video id="video2" controls></video> |
| <video id="video3" controls></video> |
| <canvas id="canvas3" width="320" height="240"></canvas> |
| <script> |
| function setupAudioContext(context, streamOrVideo) |
| { |
| var sourceNode = streamOrVideo instanceof MediaStream ? context.createMediaStreamSource(streamOrVideo) : context.createMediaElementSource(streamOrVideo); |
| |
| var analyser = context.createAnalyser(); |
| var gain = context.createGain(); |
| |
| analyser.fftSize = 2048; |
| analyser.smoothingTimeConstant = 0; |
| analyser.minDecibels = -100; |
| analyser.maxDecibels = 0; |
| gain.gain.value = 0; |
| |
| sourceNode.connect(analyser); |
| analyser.connect(gain); |
| gain.connect(context.destination); |
| |
| return analyser; |
| } |
| |
| function analyseAudio(analyser, duration, context) |
| { |
| return new Promise((resolve, reject) => { |
| var results = { heardHum: false, heardBip: false, heardBop: false, heardNoise: false }; |
| |
| function analyse() { |
| var freqDomain = new Uint8Array(analyser.frequencyBinCount); |
| analyser.getByteFrequencyData(freqDomain); |
| |
| var hasFrequency = expectedFrequency => { |
| var bin = Math.floor(expectedFrequency * analyser.fftSize / context.sampleRate); |
| return bin < freqDomain.length && freqDomain[bin] >= 150; |
| }; |
| |
| if (!results.heardHum) |
| results.heardHum = hasFrequency(150); |
| |
| if (!results.heardBip) |
| results.heardBip = hasFrequency(1500); |
| |
| if (!results.heardBop) |
| results.heardBop = hasFrequency(500); |
| |
| if (!results.heardNoise) |
| results.heardNoise = hasFrequency(3000); |
| |
| if (results.heardHum && results.heardBip && results.heardBop && results.heardNoise) |
| done(); |
| }; |
| |
| function done() { |
| clearTimeout(timeout); |
| clearInterval(interval); |
| |
| resolve(results); |
| } |
| |
| var timeout = setTimeout(done, 3 * duration); |
| var interval = setInterval(analyse, duration / 30); |
| analyse(); |
| }); |
| } |
| |
| function waitFor(duration) |
| { |
| return new Promise((resolve) => setTimeout(resolve, duration)); |
| } |
| |
| async function doHumAnalysis(streamOrVideo, expected) |
| { |
| let context = new AudioContext(); |
| let analyser = setupAudioContext(context, streamOrVideo); |
| for (var cptr = 0; cptr < 20; cptr++) { |
| const results = await analyseAudio(analyser, 200, context); |
| if (results.heardHum === expected) { |
| await context.close(); |
| return true; |
| } |
| await waitFor(50); |
| } |
| await context.close(); |
| return false; |
| } |
| |
| function isVideoBlack(canvas, video, startX, startY, grabbedWidth, grabbedHeight) |
| { |
| canvas.width = video.videoWidth; |
| canvas.height = video.videoHeight; |
| if (!grabbedHeight) { |
| startX = 10; |
| startY = 10; |
| grabbedWidth = canvas.width - 20; |
| grabbedHeight = canvas.height - 20; |
| } |
| |
| canvas.getContext('2d').drawImage(video, 0, 0, canvas.width, canvas.height); |
| |
| imageData = canvas.getContext('2d').getImageData(startX, startY, grabbedWidth, grabbedHeight); |
| data = imageData.data; |
| for (var cptr = 0; cptr < grabbedWidth * grabbedHeight; ++cptr) { |
| // Approximatively black pixels. |
| if (data[4 * cptr] > 30 || data[4 * cptr + 1] > 30 || data[4 * cptr + 2] > 30) |
| return false; |
| } |
| return true; |
| } |
| |
| async function checkVideoBlack(expected, canvas, video, errorMessage, counter) |
| { |
| if (isVideoBlack(canvas, video) === expected) |
| return Promise.resolve(); |
| |
| if (counter === undefined) |
| counter = 0; |
| if (counter > 100) { |
| if (!errorMessage) |
| errorMessage = "checkVideoBlack timed out expecting " + expected; |
| return Promise.reject(errorMessage); |
| } |
| |
| await waitFor(50); |
| return checkVideoBlack(expected, canvas, video, errorMessage, ++counter); |
| } |
| |
| promise_test(async (test) => { |
| const stream = await navigator.mediaDevices.getUserMedia({ audio: true, video: false }); |
| |
| const localTrack = stream.getAudioTracks()[0]; |
| localTrack.enabled = false; |
| setTimeout(() => localTrack.enabled = false, 0); |
| const recorder = new MediaRecorder(stream); |
| const dataPromise = new Promise(resolve => recorder.ondataavailable = (e) => resolve(e.data)); |
| |
| recorder.start(); |
| await waitFor(1000); |
| recorder.stop(); |
| const blob = await dataPromise; |
| |
| const url = URL.createObjectURL(blob); |
| video1.src = url; |
| await video1.play(); |
| |
| assert_greater_than(video1.duration, 0.5); |
| |
| const results = await doHumAnalysis(video1, false); |
| assert_true(results, "Should not hear hum"); |
| |
| URL.revokeObjectURL(url); |
| }, "Recording a muted audio track should produce silence"); |
| |
| promise_test(async (test) => { |
| const stream = await navigator.mediaDevices.getUserMedia({ audio: true, video: true }); |
| |
| const localTrack = stream.getAudioTracks()[0]; |
| setTimeout(() => localTrack.enabled = false, 50); |
| const recorder = new MediaRecorder(stream); |
| const dataPromise = new Promise(resolve => recorder.ondataavailable = (e) => resolve(e.data)); |
| |
| recorder.start(); |
| await waitFor(1000); |
| recorder.stop(); |
| const blob = await dataPromise; |
| |
| const url = URL.createObjectURL(blob); |
| video2.src = url; |
| await video2.play(); |
| |
| assert_greater_than(video2.duration, 0.5); |
| |
| const results = await doHumAnalysis(video2, false); |
| assert_true(results, "Should not hear hum"); |
| |
| URL.revokeObjectURL(url); |
| }, "Muting an audio track should record silence"); |
| |
| promise_test(async (test) => { |
| const stream = await navigator.mediaDevices.getUserMedia({ audio: true, video: true }); |
| |
| const localTrack = stream.getVideoTracks()[0]; |
| setTimeout(() => localTrack.enabled = false, 50); |
| const recorder = new MediaRecorder(stream); |
| const dataPromise = new Promise(resolve => recorder.ondataavailable = (e) => resolve(e.data)); |
| |
| recorder.start(); |
| await waitFor(1000); |
| recorder.stop(); |
| const blob = await dataPromise; |
| |
| const url = URL.createObjectURL(blob); |
| video3.src = url; |
| await video3.play(); |
| |
| assert_greater_than(video3.duration, 0.5); |
| |
| const result = await checkVideoBlack(true, canvas3, video3, "muted video should produce black frames"); |
| |
| URL.revokeObjectURL(url); |
| }, "Muting a video track should produce black frames"); |
| |
| </script> |
| </body> |
| </html> |
