Added image pattern comparison logic for test interface and fixture.

remoting/test/test_video_renderer_unittest.cc

Index: remoting/test/test_video_renderer_unittest.cc
diff --git a/remoting/test/test_video_renderer_unittest.cc b/remoting/test/test_video_renderer_unittest.cc
index 8c1d92f7fd04d30fefa57345ad3d167a0172310b..d30fd2c2400a9200d9e4a9b44caca5a3e337c793 100644
--- a/remoting/test/test_video_renderer_unittest.cc
+++ b/remoting/test/test_video_renderer_unittest.cc
@@ -9,6 +9,7 @@
 #include "base/memory/scoped_vector.h"
 #include "base/message_loop/message_loop.h"
 #include "base/run_loop.h"
+#include "base/thread_task_runner_handle.h"
 #include "base/timer/timer.h"
 #include "media/base/video_frame.h"
 #include "remoting/codec/video_encoder.h"
@@ -20,12 +21,25 @@
 #include "third_party/webrtc/modules/desktop_capture/desktop_region.h"
 
 namespace {
-const int kBytesPerPixel = 4;
-const int kDefaultScreenWidth = 1024;
-const int kDefaultScreenHeight = 768;
-const double kDefaultErrorLimit = 0.02;
+
+// Used to verify if image pattern is matched.
+void ProcessPacketDoneHandler(const base::Closure& done_closure,
+                              bool* handler_called) {
+  *handler_called = true;
+  done_closure.Run();
 }
 
+const int kDefaultScreenWidthPx = 1024;
+const int kDefaultScreenHeightPx = 768;
+
+// Default max error for encoding and decoding, measured in percent.
+const double kDefaultErrorLimit = 0.02;
+
+// Default expected rect for image pattern, measured in pixels.
+const webrtc::DesktopRect kDefaultExpectedRect =
+    webrtc::DesktopRect::MakeLTRB(100, 100, 200, 200);
+}  // namespace
+
 namespace remoting {
 namespace test {
 
@@ -36,15 +50,17 @@ class TestVideoRendererTest : public testing::Test {
   TestVideoRendererTest();
   ~TestVideoRendererTest() override;
 
-  // Generate a frame containing a gradient and test decoding of
-  // TestVideoRenderer. The original frame is compared to the one obtained from
-  // decoding the video packet, and the error at each pixel is the root mean
-  // square of the errors in the R, G and B components, each normalized to
-  // [0, 1]. This routine checks that the mean error over all pixels do not
-  // exceed a given limit.
+  // Handles creating a frame and sending to TestVideoRenderer for processing.
   void TestVideoPacketProcessing(int screen_width, int screen_height,
                                  double error_limit);
 
+  // Handles setting an image pattern and sending a frame to TestVideoRenderer.
+  // |expect_to_match| indicates if the image pattern is expected to match.
+  void TestImagePatternMatch(int screen_width,
+                             int screen_height,
+                             const webrtc::DesktopRect& expected_rect,
+                             bool expect_to_match);
+
   // Generate a basic desktop frame containing a gradient.
   scoped_ptr<webrtc::DesktopFrame> CreateDesktopFrameWithGradient(
       int screen_width, int screen_height) const;
@@ -66,7 +82,21 @@ class TestVideoRendererTest : public testing::Test {
   // testing::Test interface.
   void SetUp() override;
 
-  // return the mean error of two frames.
+  // Set image pattern, send video packet and returns if the expected pattern is
+  // matched.
+  bool SendPacketAndWaitForMatch(scoped_ptr<VideoPacket> packet,
+                                 const webrtc::DesktopRect& expected_rect,
+                                 uint32_t expected_average_color);
+
+  // Returns the average color value of pixels fall within |rect|.
+  // NOTE: Callers should not release the objects.
+  uint32_t CalculateAverageColorValueForFrame(
+      const webrtc::DesktopFrame* frame,
+      const webrtc::DesktopRect& rect) const;
+
+  // Return the mean error of two frames over all pixels, where error at each
+  // pixel is the root mean square of the errors in the R, G and B components,
+  // each normalized to [0, 1].
   double CalculateError(const webrtc::DesktopFrame* original_frame,
                         const webrtc::DesktopFrame* decoded_frame) const;
 
@@ -99,25 +129,153 @@ void TestVideoRendererTest::TestVideoPacketProcessing(int screen_width,
   DCHECK(encoder_);
   DCHECK(test_video_renderer_);
 
+  // Generate a frame containing a gradient.
   scoped_ptr<webrtc::DesktopFrame> original_frame =
       CreateDesktopFrameWithGradient(screen_width, screen_height);
   EXPECT_TRUE(original_frame);
+
   scoped_ptr<VideoPacket> packet = encoder_->Encode(*original_frame.get());
+
   DCHECK(!run_loop_ || !run_loop_->running());
+  DCHECK(!timer_->IsRunning());
   run_loop_.reset(new base::RunLoop());
 
+  // Set an extremely long time: 10 min to prevent bugs from hanging the system.
+  // NOTE: We've seen cases which take up to 1 min to process a packet, so an
+  // extremely long time as 10 min is chosen to avoid being variable/flaky.
+  timer_->Start(FROM_HERE, base::TimeDelta::FromMinutes(10),
+                run_loop_->QuitClosure());
+
   // Wait for the video packet to be processed and rendered to buffer.
   test_video_renderer_->ProcessVideoPacket(packet.Pass(),
                                            run_loop_->QuitClosure());
+
   run_loop_->Run();
+  EXPECT_TRUE(timer_->IsRunning());
+  timer_->Stop();
+  run_loop_.reset();
 
   scoped_ptr<webrtc::DesktopFrame> buffer_copy =
-      test_video_renderer_->GetBufferForTest();
+      test_video_renderer_->GetCurrentFrameForTest();
   EXPECT_NE(buffer_copy, nullptr);
+
+  // The original frame is compared to the decoded video frame to check that
+  // the mean error over all pixels does not exceed a given limit.
   double error = CalculateError(original_frame.get(), buffer_copy.get());
   EXPECT_LT(error, error_limit);
 }
 
+bool TestVideoRendererTest::SendPacketAndWaitForMatch(
+    scoped_ptr<VideoPacket> packet,
+    const webrtc::DesktopRect& expected_rect,
+    uint32_t expected_average_color) {
+  DCHECK(!run_loop_ || !run_loop_->running());
+  DCHECK(!timer_->IsRunning());
+  run_loop_.reset(new base::RunLoop());
+
+  // Set an extremely long time: 10 min to prevent bugs from hanging the system.
+  // NOTE: We've seen cases which take up to 1 min to process a packet, so an
+  // extremely long time as 10 min is chosen to avoid being variable/flaky.
+  timer_->Start(FROM_HERE, base::TimeDelta::FromMinutes(10),
+                run_loop_->QuitClosure());
+
+  // Set expected image pattern.
+  test_video_renderer_->ExpectAverageColorInRect(
+      expected_rect, expected_average_color, run_loop_->QuitClosure());
+
+  // Used to verify if the expected image pattern will be matched by |packet|.
+  scoped_ptr<VideoPacket> packet_copy(new VideoPacket(*packet.get()));
+
+  // Post first test packet: |packet|.
+  test_video_renderer_->ProcessVideoPacket(packet.Pass(),
+                                           base::Bind(&base::DoNothing));
+
+  // Second packet: |packet_copy| is posted, and |second_packet_done_callback|
+  // will always be posted back to main thread, however, whether it will be
+  // called depends on whether the expected pattern is matched or not.
+  bool second_packet_done_is_called = false;
+  base::Closure second_packet_done_callback =
+      base::Bind(&ProcessPacketDoneHandler, run_loop_->QuitClosure(),
+                 &second_packet_done_is_called);
+
+  test_video_renderer_->ProcessVideoPacket(packet_copy.Pass(),
+                                           second_packet_done_callback);
+
+  run_loop_->Run();
+  EXPECT_TRUE(timer_->IsRunning());
+  timer_->Stop();
+  run_loop_.reset();
+
+  // if expected image pattern is matched, the QuitClosure of |run_loop_| will
+  // be called before |second_packet_done_callback|, which leaves
+  // |second_packet_done_is_called| be false.
+  bool image_pattern_is_matched = !second_packet_done_is_called;
+
+  return image_pattern_is_matched;
+}
+
+void TestVideoRendererTest::TestImagePatternMatch(
+    int screen_width,
+    int screen_height,
+    const webrtc::DesktopRect& expected_rect,
+    bool expect_to_match) {
+  DCHECK(encoder_);
+  DCHECK(test_video_renderer_);
+
+  scoped_ptr<webrtc::DesktopFrame> frame =
+      CreateDesktopFrameWithGradient(screen_width, screen_height);
+  uint32_t expected_average_color =
+      CalculateAverageColorValueForFrame(frame.get(), expected_rect);
+  scoped_ptr<VideoPacket> packet = encoder_->Encode(*frame.get());
+
+  if (expect_to_match) {
+    EXPECT_TRUE(SendPacketAndWaitForMatch(packet.Pass(), expected_rect,
+                                          expected_average_color));
+  } else {
+    // Shift each channel by 128.
+    // e.g. (10, 127, 200) -> (138, 255, 73).
+    // In this way, the error between expected color and true value is always
+    // around 0.5.
+    int red_shift = (((expected_average_color >> 16) & 0xFF) + 128) % 255;
+    int green_shift = (((expected_average_color >> 8) & 0xFF) + 128) % 255;
+    int blue_shift = ((expected_average_color & 0xFF) + 128) % 255;
+
+    int expected_average_color_shift =
+        0xFF000000 | (red_shift << 16) | (green_shift << 8) | blue_shift;
+
+    EXPECT_FALSE(SendPacketAndWaitForMatch(packet.Pass(), expected_rect,
+                                           expected_average_color_shift));
+  }
+}
+
+uint32_t TestVideoRendererTest::CalculateAverageColorValueForFrame(
+    const webrtc::DesktopFrame* frame,
+    const webrtc::DesktopRect& rect) const {
+  int red_sum = 0;
+  int green_sum = 0;
+  int blue_sum = 0;
+
+  // Loop through pixels that fall within |accumulating_rect_| to obtain the
+  // average color value.
+  for (int y = rect.top(); y < rect.bottom(); ++y) {
+    uint8_t* frame_pos =
+        frame->data() + (y * frame->stride() +
+                         rect.left() * webrtc::DesktopFrame::kBytesPerPixel);
+
+    // Pixels of decoded video frame are presented in ARGB format.
+    for (int x = 0; x < rect.width(); ++x) {
+      red_sum += frame_pos[2];
+      green_sum += frame_pos[1];
+      blue_sum += frame_pos[0];
+      frame_pos += 4;
+    }
+  }
+
+  int area = rect.width() * rect.height();
+  return 0xFF000000 | ((red_sum / area) << 16) | ((green_sum / area) << 8) |
+         (blue_sum / area);
+}
+
 double TestVideoRendererTest::CalculateError(
     const webrtc::DesktopFrame* original_frame,
     const webrtc::DesktopFrame* decoded_frame) const {
@@ -156,7 +314,7 @@ double TestVideoRendererTest::CalculateError(
     for (int width = 0; width < screen_width; ++width) {
       // Errors are calculated in the R, G, B components.
       for (int j = 0; j < 3; ++j) {
-        int offset = kBytesPerPixel * width + j;
+        int offset = webrtc::DesktopFrame::kBytesPerPixel * width + j;
         double original_value = static_cast<double>(*(original_ptr + offset));
         double decoded_value = static_cast<double>(*(decoded_ptr + offset));
         double error = original_value - decoded_value;
@@ -201,7 +359,7 @@ TEST_F(TestVideoRendererTest, VerifyVideoDecodingForVP8) {
   encoder_ = VideoEncoderVpx::CreateForVP8();
   test_video_renderer_->SetCodecForDecoding(
       protocol::ChannelConfig::CODEC_VP8);
-  TestVideoPacketProcessing(kDefaultScreenWidth, kDefaultScreenHeight,
+  TestVideoPacketProcessing(kDefaultScreenWidthPx, kDefaultScreenHeightPx,
                             kDefaultErrorLimit);
 }
 
@@ -210,7 +368,7 @@ TEST_F(TestVideoRendererTest, VerifyVideoDecodingForVP9) {
   encoder_ = VideoEncoderVpx::CreateForVP9();
   test_video_renderer_->SetCodecForDecoding(
       protocol::ChannelConfig::CODEC_VP9);
-  TestVideoPacketProcessing(kDefaultScreenWidth, kDefaultScreenHeight,
+  TestVideoPacketProcessing(kDefaultScreenWidthPx, kDefaultScreenHeightPx,
                             kDefaultErrorLimit);
 }
 
@@ -220,7 +378,7 @@ TEST_F(TestVideoRendererTest, VerifyVideoDecodingForVERBATIM) {
   encoder_.reset(new VideoEncoderVerbatim());
   test_video_renderer_->SetCodecForDecoding(
       protocol::ChannelConfig::CODEC_VERBATIM);
-  TestVideoPacketProcessing(kDefaultScreenWidth, kDefaultScreenHeight,
+  TestVideoPacketProcessing(kDefaultScreenWidthPx, kDefaultScreenHeightPx,
                             kDefaultErrorLimit);
 }
 
@@ -238,8 +396,8 @@ TEST_F(TestVideoRendererTest, VerifyMultipleVideoProcessing) {
   ScopedVector<VideoPacket> video_packets;
   for (int i = 0; i < task_num; ++i) {
     scoped_ptr<webrtc::DesktopFrame> original_frame =
-        CreateDesktopFrameWithGradient(kDefaultScreenWidth,
-                                       kDefaultScreenHeight);
+        CreateDesktopFrameWithGradient(kDefaultScreenWidthPx,
+                                       kDefaultScreenHeightPx);
     video_packets.push_back(encoder_->Encode(*original_frame.get()));
   }
 
@@ -258,14 +416,94 @@ TEST_F(TestVideoRendererTest, VerifyVideoPacketSizeChange) {
   test_video_renderer_->SetCodecForDecoding(
       protocol::ChannelConfig::Codec::CODEC_VP8);
 
-  TestVideoPacketProcessing(kDefaultScreenWidth, kDefaultScreenHeight,
+  TestVideoPacketProcessing(kDefaultScreenWidthPx, kDefaultScreenHeightPx,
                             kDefaultErrorLimit);
 
-  TestVideoPacketProcessing(2 * kDefaultScreenWidth, 2 * kDefaultScreenHeight,
-                            kDefaultErrorLimit);
+  TestVideoPacketProcessing(2 * kDefaultScreenWidthPx,
+                            2 * kDefaultScreenHeightPx, kDefaultErrorLimit);
 
-  TestVideoPacketProcessing(kDefaultScreenWidth / 2, kDefaultScreenHeight / 2,
-                            kDefaultErrorLimit);
+  TestVideoPacketProcessing(kDefaultScreenWidthPx / 2,
+                            kDefaultScreenHeightPx / 2, kDefaultErrorLimit);
+}
+
+// Verify setting expected image pattern doesn't break video packet processing.
+TEST_F(TestVideoRendererTest, VerifySetExpectedImagePattern) {
+  encoder_ = VideoEncoderVpx::CreateForVP8();
+  test_video_renderer_->SetCodecForDecoding(
+      protocol::ChannelConfig::Codec::CODEC_VP8);
+
+  DCHECK(encoder_);
+  DCHECK(test_video_renderer_);
+
+  scoped_ptr<webrtc::DesktopFrame> frame = CreateDesktopFrameWithGradient(
+      kDefaultScreenWidthPx, kDefaultScreenHeightPx);
+
+  // Since we don't care whether expected image pattern is matched or not in
+  // this case, an expected color is chosen arbitrarily.
+  uint32_t black_color = 0xFF000000;
+
+  // Set expected image pattern.
+  test_video_renderer_->ExpectAverageColorInRect(
+      kDefaultExpectedRect, black_color, base::Bind(&base::DoNothing));
+
+  // Post test video packet.
+  scoped_ptr<VideoPacket> packet = encoder_->Encode(*frame.get());
+  test_video_renderer_->ProcessVideoPacket(packet.Pass(),
+                                           base::Bind(&base::DoNothing));
+}
+
+// Verify correct image pattern can be matched for VP8.
+TEST_F(TestVideoRendererTest, VerifyImagePatternMatchForVP8) {
+  encoder_ = VideoEncoderVpx::CreateForVP8();
+  test_video_renderer_->SetCodecForDecoding(
+      protocol::ChannelConfig::Codec::CODEC_VP8);
+  TestImagePatternMatch(kDefaultScreenWidthPx, kDefaultScreenHeightPx,
+                        kDefaultExpectedRect, true);
+}
+
+// Verify expected image pattern can be matched for VP9.
+TEST_F(TestVideoRendererTest, VerifyImagePatternMatchForVP9) {
+  encoder_ = VideoEncoderVpx::CreateForVP9();
+  test_video_renderer_->SetCodecForDecoding(
+      protocol::ChannelConfig::Codec::CODEC_VP9);
+  TestImagePatternMatch(kDefaultScreenWidthPx, kDefaultScreenHeightPx,
+                        kDefaultExpectedRect, true);
+}
+
+// Verify expected image pattern can be matched for VERBATIM.
+TEST_F(TestVideoRendererTest, VerifyImagePatternMatchForVERBATIM) {
+  encoder_.reset(new VideoEncoderVerbatim());
+  test_video_renderer_->SetCodecForDecoding(
+      protocol::ChannelConfig::Codec::CODEC_VERBATIM);
+  TestImagePatternMatch(kDefaultScreenWidthPx, kDefaultScreenHeightPx,
+                        kDefaultExpectedRect, true);
+}
+
+// Verify incorrect image pattern shouldn't be matched for VP8.
+TEST_F(TestVideoRendererTest, VerifyImagePatternNotMatchForVP8) {
+  encoder_ = VideoEncoderVpx::CreateForVP8();
+  test_video_renderer_->SetCodecForDecoding(
+      protocol::ChannelConfig::Codec::CODEC_VP8);
+  TestImagePatternMatch(kDefaultScreenWidthPx, kDefaultScreenHeightPx,
+                        kDefaultExpectedRect, false);
+}
+
+// Verify incorrect image pattern shouldn't be matched for VP9.
+TEST_F(TestVideoRendererTest, VerifyImagePatternNotMatchForVP9) {
+  encoder_ = VideoEncoderVpx::CreateForVP9();
+  test_video_renderer_->SetCodecForDecoding(
+      protocol::ChannelConfig::Codec::CODEC_VP9);
+  TestImagePatternMatch(kDefaultScreenWidthPx, kDefaultScreenWidthPx,
+                        kDefaultExpectedRect, false);
+}
+
+// Verify incorrect image pattern shouldn't be matched for VERBATIM.
+TEST_F(TestVideoRendererTest, VerifyImagePatternNotMatchForVERBATIM) {
+  encoder_.reset(new VideoEncoderVerbatim());
+  test_video_renderer_->SetCodecForDecoding(
+      protocol::ChannelConfig::Codec::CODEC_VERBATIM);
+  TestImagePatternMatch(kDefaultScreenWidthPx, kDefaultScreenHeightPx,
+                        kDefaultExpectedRect, false);
 }
 
 }  // namespace test