src/remoting/host/video_frame_recorder.cc

   1 // Copyright 2014 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "remoting/host/video_frame_recorder.h"
   6
   7 #include "base/bind.h"
   8 #include "base/location.h"
   9 #include "base/single_thread_task_runner.h"
  10 #include "base/stl_util.h"
  11 #include "base/thread_task_runner_handle.h"
  12 #include "remoting/codec/video_encoder.h"
  13 #include "remoting/proto/video.pb.h"
  14 #include "third_party/webrtc/modules/desktop_capture/desktop_frame.h"
  15 #include "third_party/webrtc/modules/desktop_capture/desktop_geometry.h"
  16 #include "third_party/webrtc/modules/desktop_capture/desktop_region.h"
  17
  18 namespace remoting {
  19
  20 static int64_t FrameContentSize(const webrtc::DesktopFrame* frame) {
  21   DCHECK_GT(frame->stride(), 0);
  22   return frame->stride() * frame->size().height();
  23 }
  24
  25 // VideoEncoder wrapper used to intercept frames passed to a real VideoEncoder.
  26 class VideoFrameRecorder::RecordingVideoEncoder : public VideoEncoder {
  27  public:
  28   RecordingVideoEncoder(scoped_ptr<VideoEncoder> encoder,
  29                         scoped_refptr<base::TaskRunner> recorder_task_runner,
  30                         base::WeakPtr<VideoFrameRecorder> recorder);
  31
  32   base::WeakPtr<RecordingVideoEncoder> AsWeakPtr();
  33
  34   void set_enable_recording(bool enable_recording) {
  35     DCHECK(!encoder_task_runner_.get() ||
  36            encoder_task_runner_->BelongsToCurrentThread());
  37     enable_recording_ = enable_recording;
  38   }
  39
  40   // remoting::VideoEncoder interface.
  41   virtual void SetLosslessEncode(bool want_lossless) OVERRIDE;
  42   virtual void SetLosslessColor(bool want_lossless) OVERRIDE;
  43   virtual scoped_ptr<VideoPacket> Encode(
  44       const webrtc::DesktopFrame& frame) OVERRIDE;
  45
  46  private:
  47   scoped_ptr<VideoEncoder> encoder_;
  48   scoped_refptr<base::TaskRunner> recorder_task_runner_;
  49   base::WeakPtr<VideoFrameRecorder> recorder_;
  50
  51   bool enable_recording_;
  52   scoped_refptr<base::SingleThreadTaskRunner> encoder_task_runner_;
  53
  54   base::WeakPtrFactory<RecordingVideoEncoder> weak_factory_;
  55
  56   DISALLOW_COPY_AND_ASSIGN(RecordingVideoEncoder);
  57 };
  58
  59 VideoFrameRecorder::RecordingVideoEncoder::RecordingVideoEncoder(
  60     scoped_ptr<VideoEncoder> encoder,
  61     scoped_refptr<base::TaskRunner> recorder_task_runner,
  62     base::WeakPtr<VideoFrameRecorder> recorder)
  63     : encoder_(encoder.Pass()),
  64       recorder_task_runner_(recorder_task_runner),
  65       recorder_(recorder),
  66       enable_recording_(false),
  67       weak_factory_(this) {
  68   DCHECK(encoder_);
  69   DCHECK(recorder_task_runner_.get());
  70 }
  71
  72 base::WeakPtr<VideoFrameRecorder::RecordingVideoEncoder>
  73 VideoFrameRecorder::RecordingVideoEncoder::AsWeakPtr() {
  74   return weak_factory_.GetWeakPtr();
  75 }
  76
  77 void VideoFrameRecorder::RecordingVideoEncoder::SetLosslessEncode(
  78     bool want_lossless) {
  79   encoder_->SetLosslessEncode(want_lossless);
  80 }
  81
  82 void VideoFrameRecorder::RecordingVideoEncoder::SetLosslessColor(
  83     bool want_lossless) {
  84   encoder_->SetLosslessColor(want_lossless);
  85 }
  86
  87 scoped_ptr<VideoPacket> VideoFrameRecorder::RecordingVideoEncoder::Encode(
  88     const webrtc::DesktopFrame& frame) {
  89   // If this is the first Encode() then store the TaskRunner and inform the
  90   // VideoFrameRecorder so it can post set_enable_recording() on it.
  91   if (!encoder_task_runner_.get()) {
  92     encoder_task_runner_ = base::ThreadTaskRunnerHandle::Get();
  93     recorder_task_runner_->PostTask(FROM_HERE,
  94         base::Bind(&VideoFrameRecorder::SetEncoderTaskRunner,
  95                    recorder_,
  96                    encoder_task_runner_));
  97   }
  98
  99   DCHECK(encoder_task_runner_->BelongsToCurrentThread());
 100
 101   if (enable_recording_) {
 102     // Copy the frame and post it to the VideoFrameRecorder to store.
 103     scoped_ptr<webrtc::DesktopFrame> frame_copy(
 104         new webrtc::BasicDesktopFrame(frame.size()));
 105     *frame_copy->mutable_updated_region() = frame.updated_region();
 106     frame_copy->set_dpi(frame.dpi());
 107     frame_copy->CopyPixelsFrom(frame.data(),
 108                                frame.stride(),
 109                                webrtc::DesktopRect::MakeSize(frame.size()));
 110     recorder_task_runner_->PostTask(FROM_HERE,
 111         base::Bind(&VideoFrameRecorder::RecordFrame,
 112                    recorder_,
 113                    base::Passed(&frame_copy)));
 114   }
 115
 116   return encoder_->Encode(frame);
 117 }
 118
 119 VideoFrameRecorder::VideoFrameRecorder()
 120     : content_bytes_(0),
 121       max_content_bytes_(0),
 122       enable_recording_(false),
 123       weak_factory_(this) {
 124 }
 125
 126 VideoFrameRecorder::~VideoFrameRecorder() {
 127   DetachVideoEncoderWrapper();
 128 }
 129
 130 scoped_ptr<VideoEncoder> VideoFrameRecorder::WrapVideoEncoder(
 131     scoped_ptr<VideoEncoder> encoder) {
 132   DCHECK(!encoder_task_runner_.get());
 133   DCHECK(!caller_task_runner_.get());
 134   caller_task_runner_ = base::ThreadTaskRunnerHandle::Get();
 135
 136   scoped_ptr<RecordingVideoEncoder> recording_encoder(
 137       new RecordingVideoEncoder(encoder.Pass(),
 138                                 caller_task_runner_,
 139                                 weak_factory_.GetWeakPtr()));
 140   recording_encoder_ = recording_encoder->AsWeakPtr();
 141
 142   return recording_encoder.PassAs<VideoEncoder>();
 143 }
 144
 145 void VideoFrameRecorder::DetachVideoEncoderWrapper() {
 146   DCHECK(!caller_task_runner_.get() ||
 147          caller_task_runner_->BelongsToCurrentThread());
 148
 149   // Immediately detach the wrapper from this recorder.
 150   weak_factory_.InvalidateWeakPtrs();
 151
 152   // Clean up any pending recorded frames.
 153   STLDeleteElements(&recorded_frames_);
 154   content_bytes_ = 0;
 155
 156   // Tell the wrapper to stop recording and posting frames to us.
 157   if (encoder_task_runner_.get()) {
 158     encoder_task_runner_->PostTask(FROM_HERE,
 159         base::Bind(&RecordingVideoEncoder::set_enable_recording,
 160                    recording_encoder_, false));
 161   }
 162
 163   // Detach this recorder from the calling and encode threads.
 164   caller_task_runner_ = NULL;
 165   encoder_task_runner_ = NULL;
 166 }
 167
 168 void VideoFrameRecorder::SetEnableRecording(bool enable_recording) {
 169   DCHECK(!caller_task_runner_.get() ||
 170          caller_task_runner_->BelongsToCurrentThread());
 171
 172   if (enable_recording_ == enable_recording) {
 173     return;
 174   }
 175   enable_recording_ = enable_recording;
 176
 177   if (encoder_task_runner_.get()) {
 178     encoder_task_runner_->PostTask(FROM_HERE,
 179         base::Bind(&RecordingVideoEncoder::set_enable_recording,
 180                    recording_encoder_,
 181                    enable_recording_));
 182   }
 183 }
 184
 185 void VideoFrameRecorder::SetMaxContentBytes(int64_t max_content_bytes) {
 186   DCHECK(!caller_task_runner_.get() ||
 187          caller_task_runner_->BelongsToCurrentThread());
 188   DCHECK_GE(max_content_bytes, 0);
 189
 190   max_content_bytes_ = max_content_bytes;
 191 }
 192
 193 scoped_ptr<webrtc::DesktopFrame> VideoFrameRecorder::NextFrame() {
 194   DCHECK(caller_task_runner_->BelongsToCurrentThread());
 195
 196   scoped_ptr<webrtc::DesktopFrame> frame;
 197   if (!recorded_frames_.empty()) {
 198     frame.reset(recorded_frames_.front());
 199     recorded_frames_.pop_front();
 200     content_bytes_ -= FrameContentSize(frame.get());
 201     DCHECK_GE(content_bytes_, 0);
 202   }
 203
 204   return frame.Pass();
 205 }
 206
 207 void VideoFrameRecorder::SetEncoderTaskRunner(
 208     scoped_refptr<base::TaskRunner> task_runner) {
 209   DCHECK(caller_task_runner_->BelongsToCurrentThread());
 210   DCHECK(!encoder_task_runner_.get());
 211   DCHECK(task_runner.get());
 212
 213   encoder_task_runner_ = task_runner;
 214
 215   // If the caller already enabled recording, inform the recording encoder.
 216   if (enable_recording_ && encoder_task_runner_.get()) {
 217     encoder_task_runner_->PostTask(FROM_HERE,
 218         base::Bind(&RecordingVideoEncoder::set_enable_recording,
 219                    recording_encoder_,
 220                    enable_recording_));
 221   }
 222 }
 223
 224 void VideoFrameRecorder::RecordFrame(scoped_ptr<webrtc::DesktopFrame> frame) {
 225   DCHECK(caller_task_runner_->BelongsToCurrentThread());
 226
 227   int64_t frame_bytes = FrameContentSize(frame.get());
 228   DCHECK_GE(frame_bytes, 0);
 229
 230   // Purge existing frames until there is space for the new one.
 231   while (content_bytes_ + frame_bytes > max_content_bytes_ &&
 232          !recorded_frames_.empty()) {
 233     scoped_ptr<webrtc::DesktopFrame> drop_frame(recorded_frames_.front());
 234     recorded_frames_.pop_front();
 235     content_bytes_ -= FrameContentSize(drop_frame.get());
 236     DCHECK_GE(content_bytes_, 0);
 237   }
 238
 239   // If the frame is still too big, ignore it.
 240   if (content_bytes_ + frame_bytes > max_content_bytes_) {
 241     return;
 242   }
 243
 244   // Store the frame and update the content byte count.
 245   recorded_frames_.push_back(frame.release());
 246   content_bytes_ += frame_bytes;
 247 }
 248
 249 }  // namespace remoting