Contentbrowsertest for verifying that a black frame is sent on a peerconnection if a track is disab…

content/test/data/media/webrtc_test_utilities.js

 // Copyright (c) 2012 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.
 
 // These must match with how the video and canvas tags are declared in html.
 const VIDEO_TAG_WIDTH = 320;
 const VIDEO_TAG_HEIGHT = 240;
 
 // Fake video capture background green is of value 135.
 const COLOR_BACKGROUND_GREEN = 135;
@@ skipping 34 matching lines @@
 }
 
 function detectVideoStopped(videoElementName, callback) {
   detectVideo(videoElementName,
               function (pixels, previous_pixels) {
                 return !isVideoPlaying(pixels, previous_pixels);
               },
               callback);
 }
 
+function detectBlackVideo(videoElementName, callback) {
+  detectVideo(videoElementName,
+              function (pixels, previous_pixels) {
+                return isVideoBlack(pixels);
+              },
+              callback);
+}
+
 function detectVideo(videoElementName, predicate, callback) {
   console.log('Looking at video in element ' + videoElementName);
 
   var width = VIDEO_TAG_WIDTH;
   var height = VIDEO_TAG_HEIGHT;
   var videoElement = $(videoElementName);
   var canvas = $(videoElementName + '-canvas');
   var oldPixels = [];
   var waitVideo = setInterval(function() {
     var context = canvas.getContext('2d');
@@ skipping 25 matching lines @@
 function waitForVideo(videoElement) {
   addExpectedEvent();
   detectVideoPlaying(videoElement, function () { eventOccured(); });
 }
 
 function waitForVideoToStop(videoElement) {
   addExpectedEvent();
   detectVideoStopped(videoElement, function () { eventOccured(); });
 }
 
+function waitForBlackVideo(videoElement) {
+  addExpectedEvent();
+  detectBlackVideo(videoElement, function () { eventOccured(); });
+}
+
 // Calculates the current frame rate and compares to |expected_frame_rate|
 // |callback| is triggered with value |true| if the calculated frame rate
 // is +-1 the expected or |false| if five calculations fail to match
 // |expected_frame_rate|.
 function validateFrameRate(videoElementName, expected_frame_rate, callback) {
   var videoElement = $(videoElementName);
   var startTime = new Date().getTime();
   var decodedFrames = videoElement.webkitDecodedFrameCount;
   var attempts = 0;
 
@@ skipping 54 matching lines @@
 // pixels are changed.
 function isVideoPlaying(pixels, previousPixels) {
   for (var i = 0; i < pixels.length; i++) {
     if (pixels[i] != previousPixels[i]) {
       return true;
     }
   }
   return false;
 }
 
+function isVideoBlack(pixels) {
+  for (var i = 0; i < pixels.length; i++) {
+    // |pixels| is in RGBA. Ignore the alpha channel.
+    if (pixels[i] != 0 && (i + 1) % 4 != 0) {
+      return false;
+    }
+  }
+  return true;
+}
+
 // This function matches |left| and |right| and fails the test if the
 // values don't match using normal javascript equality (i.e. the hard
 // types of the operands aren't checked).
 function assertEquals(expected, actual) {
   if (actual != expected) {
     failTest("expected '" + expected + "', got '" + actual + "'.");
   }
 }
 
 function assertNotEquals(expected, actual) {
   if (actual === expected) {
     failTest("expected '" + expected + "', got '" + actual + "'.");
   }
 }