Implement audio/video sync instrumentation for WebRTC

Draw a sweeping circle animation and elapsed time in the fake 
video stream. Combined with a synchronized beep sound in the fake
audio stream.

Tested local-to-local PeerConnection to show that audio/video are
in sync.

BUG=159053


Review URL: https://chromiumcodereview.appspot.com/11358018

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@165619 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 58 insertions, 10 deletions

diff --git a/media/video/capture/fake_video_capture_device.cc b/media/video/capture/fake_video_capture_device.cc
index 77afe8e..b137192 100644
--- a/media/video/capture/fake_video_capture_device.cc
+++ b/media/video/capture/fake_video_capture_device.cc
@@ -9,6 +9,10 @@
 #include "base/bind.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/stringprintf.h"
+#include "media/audio/fake_audio_input_stream.h"
+#include "third_party/skia/include/core/SkBitmap.h"
+#include "third_party/skia/include/core/SkCanvas.h"
+#include "third_party/skia/include/core/SkPaint.h"
 
 namespace media {
 
@@ -54,7 +58,9 @@ FakeVideoCaptureDevice::FakeVideoCaptureDevice(const Name& device_name)
       state_(kIdle),
       capture_thread_("CaptureThread"),
       frame_size_(0),
-      frame_count_(0) {
+      frame_count_(0),
+      frame_width_(0),
+      frame_height_(0) {
 }
 
 FakeVideoCaptureDevice::~FakeVideoCaptureDevice() {
@@ -91,6 +97,8 @@ void FakeVideoCaptureDevice::Allocate(int width,
   fake_frame_.reset(new uint8[fake_frame_size]);
   memset(fake_frame_.get(), 0, fake_frame_size);
   frame_size_ = fake_frame_size;
+  frame_width_ = current_settings.width;
+  frame_height_ = current_settings.height;
 
   state_ = kAllocated;
   observer_->OnFrameInfo(current_settings);
@@ -133,12 +141,54 @@ void FakeVideoCaptureDevice::OnCaptureTask() {
     return;
   }
 
-  bool beep = false;
+  memset(fake_frame_.get(), 0, frame_size_);
+
+  SkBitmap bitmap;
+  bitmap.setConfig(SkBitmap::kA8_Config, frame_width_, frame_height_,
+                   frame_width_);
+  bitmap.setPixels(fake_frame_.get());
+
+  SkCanvas canvas(bitmap);
+
+  // Draw a sweeping circle to show an animation.
+  int radius = std::min(frame_width_, frame_height_) / 4;
+  SkRect rect = SkRect::MakeXYWH(
+      frame_width_ / 2 - radius, frame_height_ / 2 - radius,
+      2 * radius, 2 * radius);
+
+  SkPaint paint;
+  paint.setStyle(SkPaint::kFill_Style);
+
+  // Only Y plane is being drawn and this gives 50% grey on the Y
+  // plane. The result is a light green color in RGB space.
+  paint.setAlpha(128);
+
+  int end_angle = (frame_count_ % kFakeCaptureBeepCycle * 360) /
+      kFakeCaptureBeepCycle;
+  if (!end_angle)
+    end_angle = 360;
+  canvas.drawArc(rect, 0, end_angle, true, paint);
+
+  // Draw current time.
+  int elapsed_ms = kFakeCaptureTimeoutMs * frame_count_;
+  int milliseconds = elapsed_ms % 1000;
+  int seconds = (elapsed_ms / 1000) % 60;
+  int minutes = (elapsed_ms / 1000 / 60) % 60;
+  int hours = (elapsed_ms / 1000 / 60 / 60) % 60;
+
+  std::string time_string =
+      base::StringPrintf("%d:%02d:%02d:%03d %d", hours, minutes,
+                         seconds, milliseconds, frame_count_);
+  canvas.scale(3, 3);
+  canvas.drawText(time_string.data(), time_string.length(), 30, 20,
+                  paint);
+
   if (frame_count_ % kFakeCaptureBeepCycle == 0) {
-    beep = true;
-    // This will fill the frame in grey.
-    memset(fake_frame_.get(), 128, frame_size_);
-  }
+    // Generate a synchronized beep sound if there is one audio input
+    // stream created.
+    FakeAudioInputStream::BeepOnce();
+ }
+
   frame_count_++;
 
   // Give the captured frame to the observer.
@@ -151,10 +201,6 @@ void FakeVideoCaptureDevice::OnCaptureTask() {
         base::Bind(&FakeVideoCaptureDevice::OnCaptureTask,
                    base::Unretained(this)),
         base::TimeDelta::FromMilliseconds(kFakeCaptureTimeoutMs));
-
-  if (beep) {
-    memset(fake_frame_.get(), 0, frame_size_);
-  }
 }
 
 }  // namespace media
diff --git a/media/video/capture/fake_video_capture_device.h b/media/video/capture/fake_video_capture_device.h
index 082bc0e..7350982 100644
--- a/media/video/capture/fake_video_capture_device.h
+++ b/media/video/capture/fake_video_capture_device.h
@@ -56,6 +56,8 @@ class MEDIA_EXPORT FakeVideoCaptureDevice : public VideoCaptureDevice {
   int frame_size_;
   scoped_array<uint8> fake_frame_;
   int frame_count_;
+  int frame_width_;
+  int frame_height_;
 
   static bool fail_next_create_;