Tab Capture: Backing store readbacks to YV12 VideoFrames.

content/browser/renderer_host/media/web_contents_video_capture_device_unittest.cc

Index: content/browser/renderer_host/media/web_contents_video_capture_device_unittest.cc
diff --git a/content/browser/renderer_host/media/web_contents_video_capture_device_unittest.cc b/content/browser/renderer_host/media/web_contents_video_capture_device_unittest.cc
index 6af0c05295a30b3c1740080d2cd98f055fca95f2..5452e0265bea00642b4bfe106c34e815d62b0523 100644
--- a/content/browser/renderer_host/media/web_contents_video_capture_device_unittest.cc
+++ b/content/browser/renderer_host/media/web_contents_video_capture_device_unittest.cc
@@ -13,6 +13,7 @@
 #include "content/browser/renderer_host/render_widget_host_impl.h"
 #include "content/public/test/mock_render_process_host.h"
 #include "content/public/test/test_browser_context.h"
+#include "media/base/video_util.h"
 #include "media/video/capture/video_capture_types.h"
 #include "skia/ext/platform_canvas.h"
 #include "testing/gtest/include/gtest/gtest.h"
@@ -39,7 +40,8 @@ class StubRenderWidgetHost : public RenderWidgetHostImpl {
       : RenderWidgetHostImpl(&delegate_, process, routing_id),
         color_(kNothingYet),
         copy_result_size_(kTestWidth, kTestHeight),
-        copy_event_(false, false) {}
+        copy_event_(false, false),
+        use_video_frames_(false) {}
 
   void SetSolidColor(SkColor color) {
     base::AutoLock guard(lock_);
@@ -51,6 +53,10 @@ class StubRenderWidgetHost : public RenderWidgetHostImpl {
     copy_result_size_ = gfx::Size(width, height);
   }
 
+  void SetUseVideoFrames(bool use_them) {
+    use_video_frames_ = use_them;
+  }
+
   bool WaitForNextBackingStoreCopy() {
     if (!copy_event_.TimedWait(kWaitTimeout)) {
       ADD_FAILURE() << "WaitForNextBackingStoreCopy: wait deadline exceeded";
@@ -79,6 +85,22 @@ class StubRenderWidgetHost : public RenderWidgetHostImpl {
     copy_event_.Signal();
   }
 
+  virtual bool CanCopyToVideoFrame() const OVERRIDE {
+    return use_video_frames_;
+  }
+
+  virtual void CopyFromBackingStoreToVideoFrame(
+      const gfx::Rect& src_rect,
+      const gfx::Size& dst_size,
+      const base::Callback<void(media::VideoFrame*)>& callback) OVERRIDE {
+    callback.Run(
+        media::VideoFrame::CreateColorFrame(
+            dst_size,
+            SkColorGetR(color_), SkColorGetG(color_), SkColorGetB(color_),
+            base::TimeDelta()));
+    copy_event_.Signal();
+  }
+
  private:
   class StubRenderWidgetHostDelegate : public RenderWidgetHostDelegate {
    public:
@@ -94,6 +116,7 @@ class StubRenderWidgetHost : public RenderWidgetHostImpl {
   SkColor color_;
   gfx::Size copy_result_size_;
   base::WaitableEvent copy_event_;
+  bool use_video_frames_;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(StubRenderWidgetHost);
 };
@@ -152,6 +175,35 @@ class StubConsumer : public media::VideoCaptureDevice::EventHandler {
     }
   }
 
+  virtual void OnIncomingCapturedVideoFrame(media::VideoFrame* frame,
+                                            base::Time timestamp) OVERRIDE {
+    EXPECT_EQ(gfx::Size(kTestWidth, kTestHeight), frame->coded_size());
+    EXPECT_EQ(media::VideoFrame::YV12, frame->format());
+    bool all_pixels_are_the_same_color = true;
+    uint8 yuv[3] = {0};
+    for (int plane = 0; plane < 3; ++plane) {
+      yuv[plane] = frame->data(plane)[0];
+      for (int y = 0; y < frame->rows(plane); ++y) {
+        for (int x = 0; x < frame->row_bytes(plane); ++x) {
+          if (yuv[plane] != frame->data(plane)[x + y * frame->stride(plane)]) {
+            all_pixels_are_the_same_color = false;
+            break;
+          }
+        }
+      }
+    }
+    EXPECT_TRUE(all_pixels_are_the_same_color);
+    const SkColor color = SkColorSetRGB(yuv[0], yuv[1], yuv[2]);
+
+    {
+      base::AutoLock guard(lock_);
+      if (color != picture_color_) {
+        picture_color_ = color;
+        output_changed_.Signal();
+      }
+    }
+  }
+
   virtual void OnError() OVERRIDE {
     base::AutoLock guard(lock_);
     error_encountered_ = true;
@@ -242,14 +294,19 @@ TEST_F(WebContentsVideoCaptureDeviceTest, GoesThroughAllTheMotions) {
                      consumer());
 
   device()->Start();
-  source()->SetSolidColor(SK_ColorRED);
-  EXPECT_TRUE(consumer()->WaitForNextColorOrError(SK_ColorRED));
-  source()->SetSolidColor(SK_ColorGREEN);
-  EXPECT_TRUE(consumer()->WaitForNextColorOrError(SK_ColorGREEN));
-  source()->SetSolidColor(SK_ColorBLUE);
-  EXPECT_TRUE(consumer()->WaitForNextColorOrError(SK_ColorBLUE));
-  source()->SetSolidColor(SK_ColorBLACK);
-  EXPECT_TRUE(consumer()->WaitForNextColorOrError(SK_ColorBLACK));
+
+  for (int i = 0; i < 4; i++) {
+    source()->SetUseVideoFrames(i % 2 == 1);

[scherkus (not reviewing), 2013/02/05 22:40:44]

how will we know which code path failed if any of these expectations failed?

is running this test in a for loop required or are you trying to avoid
duplicating code?

I'd recommend one of the following, with a preference for either 3 or 4:
  1) Duplicate the code
  2) Move some of these expectations into WCVCDTest as a helper function
  3) Use SCOPED_TRACE() so we know the state of the test when something fails
  4) Make this a parameterized test using Bool() that flips SetUseVideoFrames()
via GetParam()

[ncarter (slow), 2013/02/06 23:54:44]

Added a SCOPED_TRACE() and a comment. The test is simulating intentionally
switching from the SkBitmap to the VideoFrame codepath, which the real code
would do e.g. as you fall in and out of accelerated compositing.

[scherkus (not reviewing), 2013/02/07 18:25:03]

I had a feeling this test was doing that! Cool!

Thanks for updating the comment.

+    source()->SetSolidColor(SK_ColorRED);
+    source()->WaitForNextBackingStoreCopy();
+    EXPECT_TRUE(consumer()->WaitForNextColorOrError(SK_ColorRED));
+    source()->SetSolidColor(SK_ColorGREEN);
+    EXPECT_TRUE(consumer()->WaitForNextColorOrError(SK_ColorGREEN));
+    source()->SetSolidColor(SK_ColorBLUE);
+    EXPECT_TRUE(consumer()->WaitForNextColorOrError(SK_ColorBLUE));
+    source()->SetSolidColor(SK_ColorBLACK);
+    EXPECT_TRUE(consumer()->WaitForNextColorOrError(SK_ColorBLACK));
+  }
 
   device()->DeAllocate();
 }