Add VideoFrameRecorder for use recording test frame sequences.

remoting/host/video_frame_recorder.cc

Index: remoting/host/video_frame_recorder.cc
diff --git a/remoting/host/video_frame_recorder.cc b/remoting/host/video_frame_recorder.cc
new file mode 100644
index 0000000000000000000000000000000000000000..cccfe7cd90b5d90e3d41c2b1fdaa8bb8b18dd635
--- /dev/null
+++ b/remoting/host/video_frame_recorder.cc
@@ -0,0 +1,207 @@
+// Copyright 2014 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.
+
+#include "remoting/host/video_frame_recorder.h"
+
+#include "base/bind.h"
+#include "base/location.h"
+#include "base/single_thread_task_runner.h"
+#include "base/stl_util.h"
+#include "base/thread_task_runner_handle.h"
+#include "remoting/codec/video_encoder.h"
+#include "remoting/proto/video.pb.h"
+#include "third_party/webrtc/modules/desktop_capture/desktop_frame.h"
+#include "third_party/webrtc/modules/desktop_capture/desktop_geometry.h"
+#include "third_party/webrtc/modules/desktop_capture/desktop_region.h"
+
+namespace remoting {
+
+static int64_t FrameContentSize(const webrtc::DesktopFrame* frame) {
+  DCHECK_GT(frame->stride(), 0);
+  return frame->stride() * frame->size().height();
+}
+
+// VideoEncoder wrapper used to intercept frames passed to a real VideoEncoder.
+class VideoFrameRecorder::RecordingVideoEncoder : public VideoEncoder {
+ public:
+  RecordingVideoEncoder(scoped_ptr<VideoEncoder> encoder,
+                        scoped_refptr<base::TaskRunner> recorder_task_runner,
+                        base::WeakPtr<VideoFrameRecorder> recorder)
+      : encoder_(encoder.Pass()),
+        recorder_task_runner_(recorder_task_runner),
+        recorder_(recorder),
+        enable_recording_(false),
+        weak_factory_(this) {
+    DCHECK(encoder_);
+    DCHECK(recorder_task_runner_);
+  }
+
+  base::WeakPtr<RecordingVideoEncoder> AsWeakPtr() {
+    return weak_factory_.GetWeakPtr();
+  }
+
+  void SetEnableRecording(bool enable_recording) {
+    DCHECK(!encoder_task_runner_ ||
+           encoder_task_runner_->BelongsToCurrentThread());
+    enable_recording_ = enable_recording;
+  }
+
+  // remoting::VideoEncoder interface.
+  virtual void SetLosslessEncode(bool want_lossless) OVERRIDE {
+    encoder_->SetLosslessEncode(want_lossless);
+  }
+  virtual void SetLosslessColor(bool want_lossless) OVERRIDE {
+    encoder_->SetLosslessColor(want_lossless);
+  }
+  virtual scoped_ptr<VideoPacket> Encode(
+      const webrtc::DesktopFrame& frame) OVERRIDE {
+    // If this is the first Encode() then store the TaskRunner and inform the
+    // VideoFrameRecorder so it can post SetEnableRecording() on it.
+    if (!encoder_task_runner_) {
+      encoder_task_runner_ = base::ThreadTaskRunnerHandle::Get();
+      recorder_task_runner_->PostTask(FROM_HERE,
+          base::Bind(&VideoFrameRecorder::SetEncoderTaskRunner,
+                     recorder_,
+                     encoder_task_runner_));
+    }
+
+    DCHECK(encoder_task_runner_->BelongsToCurrentThread());
+
+    if (enable_recording_) {
+      // Copy the frame and post it to the VideoFrameRecorder to store.
+      scoped_ptr<webrtc::DesktopFrame> frame_copy(
+          new webrtc::BasicDesktopFrame(frame.size()));
+      *frame_copy->mutable_updated_region() = frame.updated_region();
+      frame_copy->set_dpi(frame.dpi());
+      frame_copy->CopyPixelsFrom(frame.data(),
+                                 frame.stride(),
+                                 webrtc::DesktopRect::MakeSize(frame.size()));
+      recorder_task_runner_->PostTask(FROM_HERE,
+          base::Bind(&VideoFrameRecorder::RecordFrame,
+                     recorder_,
+                     base::Passed(&frame_copy)));
+    }
+
+    return encoder_->Encode(frame);
+  }
+
+ private:
+  scoped_ptr<VideoEncoder> encoder_;
+  scoped_refptr<base::TaskRunner> recorder_task_runner_;
+  base::WeakPtr<VideoFrameRecorder> recorder_;
+
+  bool enable_recording_;
+  scoped_refptr<base::SingleThreadTaskRunner> encoder_task_runner_;
+
+  base::WeakPtrFactory<RecordingVideoEncoder> weak_factory_;
+
+  DISALLOW_COPY_AND_ASSIGN(RecordingVideoEncoder);
+};
+
+VideoFrameRecorder::VideoFrameRecorder()
+    : content_bytes_(0),
+      max_content_bytes_(0),
+      enable_recording_(false),
+      weak_factory_(this) {
+}
+
+VideoFrameRecorder::~VideoFrameRecorder() {
+  SetEnableRecording(false);
+  STLDeleteElements(&recorded_frames_);
+}
+
+scoped_ptr<VideoEncoder> VideoFrameRecorder::WrapVideoEncoder(
+    scoped_ptr<VideoEncoder> encoder) {
+  DCHECK(!caller_task_runner_);
+  caller_task_runner_ = base::ThreadTaskRunnerHandle::Get();
+
+  scoped_ptr<RecordingVideoEncoder> recording_encoder(
+      new RecordingVideoEncoder(encoder.Pass(),
+                                caller_task_runner_,
+                                weak_factory_.GetWeakPtr()));
+  recording_encoder_ = recording_encoder->AsWeakPtr();
+
+  return recording_encoder.PassAs<VideoEncoder>();
+}
+
+void VideoFrameRecorder::SetEnableRecording(bool enable_recording) {
+  DCHECK(!caller_task_runner_ || caller_task_runner_->BelongsToCurrentThread());
+
+  if (enable_recording_ == enable_recording) {
+    return;
+  }
+  enable_recording_ = enable_recording;
+
+  if (encoder_task_runner_) {
+    encoder_task_runner_->PostTask(FROM_HERE,
+        base::Bind(&RecordingVideoEncoder::SetEnableRecording,
+                   recording_encoder_,
+                   enable_recording_));
+  }
+}
+
+void VideoFrameRecorder::SetMaxContentBytes(int64_t max_content_bytes) {
+  DCHECK(!caller_task_runner_ || caller_task_runner_->BelongsToCurrentThread());
+  DCHECK_GE(max_content_bytes, 0);
+
+  max_content_bytes_ = max_content_bytes;
+}
+
+scoped_ptr<webrtc::DesktopFrame> VideoFrameRecorder::NextFrame() {
+  DCHECK(caller_task_runner_->BelongsToCurrentThread());
+
+  scoped_ptr<webrtc::DesktopFrame> frame;
+  if (!recorded_frames_.empty()) {
+    frame.reset(recorded_frames_.front());
+    recorded_frames_.pop_front();
+    content_bytes_ -= FrameContentSize(frame.get());
+    DCHECK_GE(content_bytes_, 0);
+  }
+
+  return frame.Pass();
+}
+
+void VideoFrameRecorder::SetEncoderTaskRunner(
+    scoped_refptr<base::TaskRunner> task_runner) {
+  DCHECK(caller_task_runner_->BelongsToCurrentThread());
+  DCHECK(!encoder_task_runner_);
+  DCHECK(task_runner);
+
+  encoder_task_runner_ = task_runner;
+
+  // If the caller already enabled recording, inform the recording encoder.
+  if (enable_recording_ && encoder_task_runner_) {
+    encoder_task_runner_->PostTask(FROM_HERE,
+        base::Bind(&RecordingVideoEncoder::SetEnableRecording,
+                   recording_encoder_,
+                   enable_recording_));
+  }
+}
+
+void VideoFrameRecorder::RecordFrame(scoped_ptr<webrtc::DesktopFrame> frame) {
+  DCHECK(caller_task_runner_->BelongsToCurrentThread());
+
+  int64_t frame_bytes = FrameContentSize(frame.get());
+  DCHECK_GE(frame_bytes, 0);
+
+  // Purge existing frames until there is space for the new one.
+  while (content_bytes_ + frame_bytes > max_content_bytes_ &&
+         !recorded_frames_.empty()) {
+    scoped_ptr<webrtc::DesktopFrame> drop_frame(recorded_frames_.front());
+    recorded_frames_.pop_front();
+    content_bytes_ -= FrameContentSize(drop_frame.get());
+    DCHECK_GE(content_bytes_, 0);
+  }
+
+  // If the frame is still too big, ignore it.
+  if (content_bytes_ + frame_bytes > max_content_bytes_) {
+    return;
+  }
+
+  // Store the frame and update the content byte count.
+  recorded_frames_.push_back(frame.release());
+  content_bytes_ += frame_bytes;
+}
+
+}  // namespace remoting