Cast: Refactor RTCP handling

media/cast/sender/video_sender.cc

 // 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 "media/cast/sender/video_sender.h"
 
 #include <algorithm>
 #include <cstring>
 
 #include "base/bind.h"
 #include "base/debug/trace_event.h"
 #include "base/logging.h"
 #include "base/message_loop/message_loop.h"
 #include "media/cast/cast_defines.h"
 #include "media/cast/net/cast_transport_config.h"
-#include "media/cast/net/rtcp/rtcp_defines.h"
 #include "media/cast/sender/external_video_encoder.h"
 #include "media/cast/sender/video_encoder_impl.h"
 
 namespace media {
 namespace cast {
 
 const int kNumAggressiveReportsSentAtStart = 100;
 const int kMinSchedulingDelayMs = 1;
 
 VideoSender::VideoSender(
     scoped_refptr<CastEnvironment> cast_environment,
     const VideoSenderConfig& video_config,
     const CreateVideoEncodeAcceleratorCallback& create_vea_cb,
     const CreateVideoEncodeMemoryCallback& create_video_encode_mem_cb,
     CastTransportSender* const transport_sender)
-    : cast_environment_(cast_environment),
+    : FrameSender(
+        cast_environment,
+        transport_sender,
+        base::TimeDelta::FromMilliseconds(video_config.rtcp_interval),
+        kVideoFrequency,
+        video_config.ssrc),
       target_playout_delay_(video_config.target_playout_delay),
-      transport_sender_(transport_sender),
       max_unacked_frames_(
           std::min(kMaxUnackedFrames,
                    1 + static_cast<int>(target_playout_delay_ *
                                         video_config.max_frame_rate /
                                         base::TimeDelta::FromSeconds(1)))),
-      rtcp_(cast_environment_,
-            this,
-            transport_sender_,
-            NULL,  // paced sender.
-            NULL,
-            video_config.rtcp_mode,
-            base::TimeDelta::FromMilliseconds(video_config.rtcp_interval),
-            video_config.ssrc,
-            video_config.incoming_feedback_ssrc,
-            video_config.rtcp_c_name,
-            VIDEO_EVENT),
-      rtp_timestamp_helper_(kVideoFrequency),
       num_aggressive_rtcp_reports_sent_(0),
       frames_in_encoder_(0),
       last_sent_frame_id_(0),
       latest_acked_frame_id_(0),
       duplicate_ack_counter_(0),
       congestion_control_(cast_environment->Clock(),
                           video_config.max_bitrate,
                           video_config.min_bitrate,
                           max_unacked_frames_),
       cast_initialization_status_(STATUS_VIDEO_UNINITIALIZED),
       weak_factory_(this) {
   VLOG(1) << "max_unacked_frames " << max_unacked_frames_;
   DCHECK_GT(max_unacked_frames_, 0);
 
   if (video_config.use_external_encoder) {
     video_encoder_.reset(new ExternalVideoEncoder(cast_environment,
                                                   video_config,
                                                   create_vea_cb,
                                                   create_video_encode_mem_cb));
   } else {
     video_encoder_.reset(new VideoEncoderImpl(
         cast_environment, video_config, max_unacked_frames_));
   }
   cast_initialization_status_ = STATUS_VIDEO_INITIALIZED;
 
   media::cast::CastTransportRtpConfig transport_config;
   transport_config.ssrc = video_config.ssrc;
+  transport_config.feedback_ssrc = video_config.incoming_feedback_ssrc;
+  transport_config.c_name = video_config.rtcp_c_name;
   transport_config.rtp_payload_type = video_config.rtp_payload_type;
   transport_config.stored_frames = max_unacked_frames_;
   transport_config.aes_key = video_config.aes_key;
   transport_config.aes_iv_mask = video_config.aes_iv_mask;
-  transport_sender_->InitializeVideo(transport_config);
 
-  rtcp_.SetCastReceiverEventHistorySize(kReceiverRtcpEventHistorySize);
+  transport_sender->InitializeVideo(
+      transport_config,
+      base::Bind(&VideoSender::OnReceivedCastFeedback,
+                 weak_factory_.GetWeakPtr()),
+      base::Bind(&VideoSender::OnReceivedRtt, weak_factory_.GetWeakPtr()));
 
   memset(frame_id_to_rtp_timestamp_, 0, sizeof(frame_id_to_rtp_timestamp_));
 }
 
 VideoSender::~VideoSender() {
 }
 
 void VideoSender::InsertRawVideoFrame(
     const scoped_refptr<media::VideoFrame>& video_frame,
     const base::TimeTicks& capture_time) {
@@ skipping 99 matching lines @@
     VLOG_IF(1, is_last_aggressive_report) << "Sending last aggressive report.";
     SendRtcpReport(is_last_aggressive_report);
   }
 
   congestion_control_.SendFrameToTransport(
       frame_id, encoded_frame->data.size() * 8, last_send_time_);
 
   transport_sender_->InsertCodedVideoFrame(*encoded_frame);
 }
 
-void VideoSender::IncomingRtcpPacket(scoped_ptr<Packet> packet) {
+void VideoSender::ResendCheck() {
   DCHECK(cast_environment_->CurrentlyOn(CastEnvironment::MAIN));
-  rtcp_.IncomingRtcpPacket(&packet->front(), packet->size());
-}
-
-void VideoSender::ScheduleNextRtcpReport() {
-  DCHECK(cast_environment_->CurrentlyOn(CastEnvironment::MAIN));
-  base::TimeDelta time_to_next = rtcp_.TimeToSendNextRtcpReport() -
-                                 cast_environment_->Clock()->NowTicks();
-
-  time_to_next = std::max(
-      time_to_next, base::TimeDelta::FromMilliseconds(kMinSchedulingDelayMs));
-
-  cast_environment_->PostDelayedTask(
-      CastEnvironment::MAIN,
-      FROM_HERE,
-      base::Bind(&VideoSender::SendRtcpReport,
-                 weak_factory_.GetWeakPtr(),
-                 true),
-      time_to_next);
-}
-
-void VideoSender::SendRtcpReport(bool schedule_future_reports) {
-  DCHECK(cast_environment_->CurrentlyOn(CastEnvironment::MAIN));
-  const base::TimeTicks now = cast_environment_->Clock()->NowTicks();
-  uint32 now_as_rtp_timestamp = 0;
-  if (rtp_timestamp_helper_.GetCurrentTimeAsRtpTimestamp(
-          now, &now_as_rtp_timestamp)) {
-    rtcp_.SendRtcpFromRtpSender(now, now_as_rtp_timestamp);
-  } else {
-    // |rtp_timestamp_helper_| should have stored a mapping by this point.
-    NOTREACHED();
+  DCHECK(!last_send_time_.is_null());
+  const base::TimeDelta time_since_last_send =
+      cast_environment_->Clock()->NowTicks() - last_send_time_;
+  if (time_since_last_send > target_playout_delay_) {
+    if (latest_acked_frame_id_ == last_sent_frame_id_) {
+      // Last frame acked, no point in doing anything
+    } else {
+      VLOG(1) << "ACK timeout; last acked frame: " << latest_acked_frame_id_;
+      ResendForKickstart();
+    }
   }
-  if (schedule_future_reports)
-    ScheduleNextRtcpReport();
+  ScheduleNextResendCheck();
 }
 
 void VideoSender::ScheduleNextResendCheck() {
   DCHECK(cast_environment_->CurrentlyOn(CastEnvironment::MAIN));
   DCHECK(!last_send_time_.is_null());
   base::TimeDelta time_to_next =
       last_send_time_ - cast_environment_->Clock()->NowTicks() +
       target_playout_delay_;
   time_to_next = std::max(
       time_to_next, base::TimeDelta::FromMilliseconds(kMinSchedulingDelayMs));
   cast_environment_->PostDelayedTask(
       CastEnvironment::MAIN,
       FROM_HERE,
       base::Bind(&VideoSender::ResendCheck, weak_factory_.GetWeakPtr()),
       time_to_next);
 }
 
-void VideoSender::ResendCheck() {
-  DCHECK(cast_environment_->CurrentlyOn(CastEnvironment::MAIN));
-  DCHECK(!last_send_time_.is_null());
-  const base::TimeDelta time_since_last_send =
-      cast_environment_->Clock()->NowTicks() - last_send_time_;
-  if (time_since_last_send > target_playout_delay_) {
-    if (latest_acked_frame_id_ == last_sent_frame_id_) {
-      // Last frame acked, no point in doing anything
-    } else {
-      VLOG(1) << "ACK timeout; last acked frame: " << latest_acked_frame_id_;
-      ResendForKickstart();
-    }
-  }
-  ScheduleNextResendCheck();
-}
-
 void VideoSender::OnReceivedCastFeedback(const RtcpCastMessage& cast_feedback) {
   DCHECK(cast_environment_->CurrentlyOn(CastEnvironment::MAIN));
 
   base::TimeDelta rtt;
   base::TimeDelta avg_rtt;
   base::TimeDelta min_rtt;
   base::TimeDelta max_rtt;
-  if (rtcp_.Rtt(&rtt, &avg_rtt, &min_rtt, &max_rtt)) {
+  if (is_rtt_available()) {
+    rtt = rtt_;
+    avg_rtt = avg_rtt_;
+    min_rtt = min_rtt_;
+    max_rtt = max_rtt_;
+
     congestion_control_.UpdateRtt(rtt);
 
     // Don't use a RTT lower than our average.
     rtt = std::max(rtt, avg_rtt);
 
     // Having the RTT values implies the receiver sent back a receiver report
     // based on it having received a report from here.  Therefore, ensure this
     // sender stops aggressively sending reports.
     if (num_aggressive_rtcp_reports_sent_ < kNumAggressiveReportsSentAtStart) {
       VLOG(1) << "No longer a need to send reports aggressively (sent "
               << num_aggressive_rtcp_reports_sent_ << ").";
       num_aggressive_rtcp_reports_sent_ = kNumAggressiveReportsSentAtStart;
       ScheduleNextRtcpReport();
     }
   } else {
     // We have no measured value use default.
     rtt = base::TimeDelta::FromMilliseconds(kStartRttMs);
   }
 
   if (last_send_time_.is_null())
     return;  // Cannot get an ACK without having first sent a frame.
 
-  if (cast_feedback.missing_frames_and_packets_.empty()) {
-    video_encoder_->LatestFrameIdToReference(cast_feedback.ack_frame_id_);
+  if (cast_feedback.missing_frames_and_packets.empty()) {
+    video_encoder_->LatestFrameIdToReference(cast_feedback.ack_frame_id);
 
     // We only count duplicate ACKs when we have sent newer frames.
-    if (latest_acked_frame_id_ == cast_feedback.ack_frame_id_ &&
+    if (latest_acked_frame_id_ == cast_feedback.ack_frame_id &&
         latest_acked_frame_id_ != last_sent_frame_id_) {
       duplicate_ack_counter_++;
     } else {
       duplicate_ack_counter_ = 0;
     }
     // TODO(miu): The values "2" and "3" should be derived from configuration.
     if (duplicate_ack_counter_ >= 2 && duplicate_ack_counter_ % 3 == 2) {
       VLOG(1) << "Received duplicate ACK for frame " << latest_acked_frame_id_;
       ResendForKickstart();
     }
   } else {
     // Only count duplicated ACKs if there is no NACK request in between.
     // This is to avoid aggresive resend.
     duplicate_ack_counter_ = 0;
 
     // A NACK is also used to cancel pending re-transmissions.
     transport_sender_->ResendPackets(
-        false, cast_feedback.missing_frames_and_packets_, true, rtt);
+        false, cast_feedback.missing_frames_and_packets, true, rtt);
   }
 
   base::TimeTicks now = cast_environment_->Clock()->NowTicks();
-  congestion_control_.AckFrame(cast_feedback.ack_frame_id_, now);
+  congestion_control_.AckFrame(cast_feedback.ack_frame_id, now);
 
   RtpTimestamp rtp_timestamp =
-      frame_id_to_rtp_timestamp_[cast_feedback.ack_frame_id_ & 0xff];
+      frame_id_to_rtp_timestamp_[cast_feedback.ack_frame_id & 0xff];
   cast_environment_->Logging()->InsertFrameEvent(now,
                                                  FRAME_ACK_RECEIVED,
                                                  VIDEO_EVENT,
                                                  rtp_timestamp,
-                                                 cast_feedback.ack_frame_id_);
+                                                 cast_feedback.ack_frame_id);
 
   const bool is_acked_out_of_order =
-      static_cast<int32>(cast_feedback.ack_frame_id_ -
+      static_cast<int32>(cast_feedback.ack_frame_id -
                              latest_acked_frame_id_) < 0;
   VLOG(2) << "Received ACK" << (is_acked_out_of_order ? " out-of-order" : "")
-          << " for frame " << cast_feedback.ack_frame_id_;
+          << " for frame " << cast_feedback.ack_frame_id;
   if (!is_acked_out_of_order) {
     // Cancel resends of acked frames.
     MissingFramesAndPacketsMap missing_frames_and_packets;
     PacketIdSet missing;
-    while (latest_acked_frame_id_ != cast_feedback.ack_frame_id_) {
+    while (latest_acked_frame_id_ != cast_feedback.ack_frame_id) {
       latest_acked_frame_id_++;
       missing_frames_and_packets[latest_acked_frame_id_] = missing;
     }
     transport_sender_->ResendPackets(
         false, missing_frames_and_packets, true, rtt);
-    latest_acked_frame_id_ = cast_feedback.ack_frame_id_;
+    latest_acked_frame_id_ = cast_feedback.ack_frame_id;
   }
 }
 
 bool VideoSender::AreTooManyFramesInFlight() const {
   DCHECK(cast_environment_->CurrentlyOn(CastEnvironment::MAIN));
   int frames_in_flight = frames_in_encoder_;
   if (!last_send_time_.is_null()) {
     frames_in_flight +=
         static_cast<int32>(last_sent_frame_id_ - latest_acked_frame_id_);
   }
@@ skipping 12 matching lines @@
   // Send the first packet of the last encoded frame to kick start
   // retransmission. This gives enough information to the receiver what
   // packets and frames are missing.
   MissingFramesAndPacketsMap missing_frames_and_packets;
   PacketIdSet missing;
   missing.insert(kRtcpCastLastPacket);
   missing_frames_and_packets.insert(
       std::make_pair(last_sent_frame_id_, missing));
   last_send_time_ = cast_environment_->Clock()->NowTicks();
 
-  base::TimeDelta rtt;
-  base::TimeDelta avg_rtt;
-  base::TimeDelta min_rtt;
-  base::TimeDelta max_rtt;
-  rtcp_.Rtt(&rtt, &avg_rtt, &min_rtt, &max_rtt);
-
   // Sending this extra packet is to kick-start the session. There is
   // no need to optimize re-transmission for this case.
   transport_sender_->ResendPackets(false, missing_frames_and_packets,
-                                   false, rtt);
+                                   false, rtt_);
 }
 
 }  // namespace cast
 }  // namespace media