WebGL2 & 16-bit depth capture: Upload video to GL_RED float texture.

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) {
@@ skipping 54 matching lines @@
                       step * ((flip_y ? -row : row) + column)) % wrap_around;
     if (Math.abs(calculated - data[i]) > tolerance) {
       return Promise.reject(test_name + ": reference value " + data[i] +
           " differs from calculated: " + calculated +
           " at index (row, column) " + i + " (" + row + ", " + column +
           "). TopLeft value:" + data[0] + ", step:" + step + ", flip_y:" +
           flip_y);
     }
   }
   return true;
+}
+
+// Although RED texture is bound to framebuffer, we read RGBA pixels to |data|.
+// Value at point (row, column) is calculated as
+// (top_left_value + (row + column) * step) % wrap_around. wrap_around is 255
+// (for Uint8) or 1.0 for float. See FakeVideoCaptureDevice for details.
+function verifyPixelsRed(
+    data, width, height, flip_y, step, wrap_around, tolerance, test_name) {
+  var rowsColumnsToCheck = [[1, 1],
+                            [0, width - 1],
+                            [height - 1, 0],
+                            [height - 1, width - 1],
+                            [height - 3, width - 3]];
+
+  // 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 = (width * row + column) * 4;
+    var calculated = (data[0] + wrap_around +
+                      step * ((flip_y ? -row : row) + column)) % wrap_around;
+    if (Math.abs(calculated - data[i]) > tolerance) {
+      return Promise.reject(test_name + ": reference value " + data[i] +
+          " differs from calculated: " + calculated +
+          " at index (row, column) " + i + " (" + row + ", " + column +
+          "). TopLeft value:" + data[0] + ", step:" + step + ", flip_y:" +
+          flip_y);
+    }
+  }
+  return true;
 }