16 bpp video stream capture, render and createImageBitmap(video) using (CPU) shared memory buffers

content/test/data/media/depth_stream_test_utilities.js

+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+function getConstraintsForDevice(deviceLabel) {
+  return new Promise(function(resolve, reject) {
+    navigator.mediaDevices.enumerateDevices()
+    .then(function(devices) {
+      for (var i = 0; i < devices.length; ++i) {
+        if (deviceLabel == devices[i].label) {
+          return resolve({video:{deviceId: {exact: devices[i].deviceId},
+                                 width: {exact:96},
+                                 height: {exact:96}}
+                          });
+        }
+      }
+      return reject("Expected to have a device with label:" + deviceLabel);
+    })
+  });
+}
+
+function getFake16bitStream() {
+  return new Promise(function(resolve, reject) {
+    getConstraintsForDevice("fake_device_1")
+    .then(function(constraints) {
+      if (!constraints)
+        return reject("No fake device found");
+      return navigator.mediaDevices.getUserMedia(constraints);
+    }).then(function(stream) {
+      return resolve(stream);
+    });
+  });
+}
+
+function testVideoToImageBitmap(videoElementName, success, error)

[phoglund_chromium, 2016/11/02 14:52:05]

I'd move this function, and the next, to the .html file since they lay out the
test case itself, and are currently only used by one html file. The two
functions above feel more like utility functions so they can stay though. Your
call.

[aleksandar.stojiljkovic, 2016/11/02 15:10:41]

Thanks.
Yes, it is good to do but let's not do it here - already extracted common code
out of this in follow up patch while adding more tests.

+{
+  var bitmaps = {};
+  var video = $(videoElementName);
+  var canvas = document.createElement('canvas');
+  canvas.width = 96;
+  canvas.height = 96;
+  document.body.appendChild(canvas);
+  var p1 = createImageBitmap(video).then(function(imageBitmap) {
+    return runImageBitmapTest(imageBitmap, canvas, false); });
+  var p2 = createImageBitmap(video,
+      {imageOrientation: "none", premultiplyAlpha: "premultiply"}).then(
+          function(imageBitmap) {
+            return runImageBitmapTest(imageBitmap, canvas, false); });
+  var p3 = createImageBitmap(video,
+      {imageOrientation: "none", premultiplyAlpha: "default"}).then(
+          function(imageBitmap) {
+            return runImageBitmapTest(imageBitmap, canvas, false); });
+  var p4 = createImageBitmap(video,
+      {imageOrientation: "none", premultiplyAlpha: "none"}).then(
+          function(imageBitmap) {
+            return runImageBitmapTest(imageBitmap, canvas, false); });
+  var p5 = createImageBitmap(video,
+      {imageOrientation: "flipY", premultiplyAlpha: "premultiply"}).then(
+          function(imageBitmap) {
+            return runImageBitmapTest(imageBitmap, canvas, true); });
+  var p6 = createImageBitmap(video,
+      {imageOrientation: "flipY", premultiplyAlpha: "default"}).then(
+          function(imageBitmap) {
+            return runImageBitmapTest(imageBitmap, canvas, true); });
+  var p7 = createImageBitmap(video,
+      {imageOrientation: "flipY", premultiplyAlpha: "none"}).then(
+          function(imageBitmap) {
+            return runImageBitmapTest(imageBitmap, canvas, true); });
+  return Promise.all([p1, p2, p3, p4, p5, p6, p7]).then(success(), reason => {
+    return error({name: reason});
+  });
+}
+
+function runImageBitmapTest(bitmap, canvas, flipped) {
+  var context = canvas.getContext('2d');
+  context.drawImage(bitmap,0,0);
+  var imageData = context.getImageData(0, 0, canvas.width, canvas.height);
+  // Fake capture device 96x96 depth image is gradient. See also
+  // Draw16BitGradient in fake_video_capture_device.cc.
+  var color_step = 255.0 / (canvas.width + canvas.height);
+  var rowsColumnsToCheck = [[1, 1],
+                            [0, canvas.width - 1],
+                            [canvas.height - 1, 0],
+                            [canvas.height - 1, canvas.width - 1],
+                            [canvas.height - 3, canvas.width - 4]];
+
+  // Same value is expected for all color components.
+  if (imageData.data[0] != imageData.data[1] ||
+      imageData.data[0] != imageData.data[2])
+    return Promise.reject("Values " + imageData.data[0] + ", " +
+        imageData.data[1] + ", " + imageData.data[2] + " differ at top left");
+
+  // Calculate all reference points based on top left and compare.
+  for (var j = 0; j < rowsColumnsToCheck.length; ++j) {
+    var row = rowsColumnsToCheck[j][0];
+    var column = rowsColumnsToCheck[j][1];
+    var i = (canvas.width * row + column) * 4;
+    if (imageData.data[i] != imageData.data[i + 1] ||
+        imageData.data[i] != imageData.data[i + 2])
+      return Promise.reject("Values " + imageData.data[i] + ", " +
+          imageData.data[i + 1] + ", " + imageData.data[i + 2] +
+          " differ at index " + i);
+    var calculated = (imageData.data[0] +
+                      color_step * ((flipped ? -row : row) + column)) % 255;
+    if (Math.abs(calculated - imageData.data[i]) > 2)
+      return Promise.reject("Reference value " + imageData.data[i] +
+          " differs from calculated: " + calculated + " at index " + i +
+          ". TopLeft value:" + imageData.data[0]);
+  }
+  return true;
+}