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Issue 2768683002:
Fix unreliable MediaStream capture from WebGL canvases (Closed)
| Index: third_party/WebKit/LayoutTests/fast/mediacapturefromelement/CanvasCaptureMediaStream-webgl-preservedrawingbuffer-false.html |
| diff --git a/third_party/WebKit/LayoutTests/fast/mediacapturefromelement/CanvasCaptureMediaStream-webgl-preservedrawingbuffer-false.html b/third_party/WebKit/LayoutTests/fast/mediacapturefromelement/CanvasCaptureMediaStream-webgl-preservedrawingbuffer-false.html |
| new file mode 100644 |
| index 0000000000000000000000000000000000000000..cd45effa72a314a52ce91c235952fe60b38f9646 |
| --- /dev/null |
| +++ b/third_party/WebKit/LayoutTests/fast/mediacapturefromelement/CanvasCaptureMediaStream-webgl-preservedrawingbuffer-false.html |
| @@ -0,0 +1,55 @@ |
| + <!DOCTYPE html> |
| + <script src =../../resources/testharness.js></script> |
| + <script src =../../resources/testharnessreport.js></script> |
| + <body> |
| + <canvas id="output"></canvas> |
| + </body> |
| + <script> |
| + |
| +// When WebGL contexts are created with preserveDrawingBuffer set |
| +// to false, there is a risk that stream capture will occur after |
| +// the canvas has cleared its contents. This test verifies that |
| +// this is not the case. |
| + |
| +var canvas = document.getElementById('output'); |
| +var framesToTest = 4; |
| +const ON_DATA_AVAILABLE_THRESHOLD = 10; |
| + |
| +function drawWebGL() { |
| + var gl = canvas.getContext('webgl', { preserveDrawingBuffer: false }); |
| + gl.clearColor(0, 1, 0, 1); |
| + gl.clear(gl.COLOR_BUFFER_BIT); |
| + if (framesToTest > 0) |
| + requestAnimationFrame(drawWebGL); |
| +}; |
| + |
| +async_test(function(test) { |
| + var video = document.createElement('video'); |
| + var stream = canvas.captureStream(); |
| + video.srcObject = stream; |
| + recorder = new MediaRecorder(stream); |
| + var testCtx = document.createElement('canvas').getContext('2d'); |
| + |
| + recorder.ondataavailable = function(event) { |
| + if (event.data.size > ON_DATA_AVAILABLE_THRESHOLD) { |
| + test.step(function() { |
| + testCtx.drawImage(video, 0, 0); |
|
emircan
2017/03/22 18:26:26
Sorry I forgot about this earlier when we talked a
|
| + var data = testCtx.getImageData(0, 0, 1, 1).data; |
| + // Equality is approximate because the video encoding is lossy. |
| + assert_approx_equals(data[0], 0, 4, 'The red component.'); |
| + assert_approx_equals(data[1], 255, 4, 'The green component.'); |
| + assert_approx_equals(data[2], 0, 4, 'The blue component.'); |
| + assert_approx_equals(data[3], 255, 4, 'The alpha component.'); |
| + }); |
| + framesToTest = framesToTest - 1 |
| + if (framesToTest == 0) { |
| + test.done(); |
| + } |
| + } |
| + } |
| + |
| + recorder.start(0); |
| + drawWebGL(); |
| +}, 'Encode succeeds with captureStream() on an animated canvas with WebGL.'); |
| + |
| +</script> |
