Cast: Merge common functionality from audio/video sender into frame_sender.

media/cast/sender/audio_sender.cc

Index: media/cast/sender/audio_sender.cc
diff --git a/media/cast/sender/audio_sender.cc b/media/cast/sender/audio_sender.cc
index a36e6de882ccdf64c0b732927fda7eabadc764dd..0a458911358c5af323ff1320be4e81deed858665 100644
--- a/media/cast/sender/audio_sender.cc
+++ b/media/cast/sender/audio_sender.cc
@@ -15,8 +15,6 @@ namespace media {
 namespace cast {
 namespace {
 
-const int kNumAggressiveReportsSentAtStart = 100;
-
 // TODO(miu): This should be specified in AudioSenderConfig, but currently it is
 // fixed to 100 FPS (i.e., 10 ms per frame), and AudioEncoder assumes this as
 // well.
@@ -29,13 +27,15 @@ AudioSender::AudioSender(scoped_refptr<CastEnvironment> cast_environment,
                          CastTransportSender* const transport_sender)
     : FrameSender(
         cast_environment,
+        true,
         transport_sender,
         base::TimeDelta::FromMilliseconds(audio_config.rtcp_interval),
         audio_config.frequency,
         audio_config.ssrc,
         kAudioFrameRate * 2.0, // We lie to increase max outstanding frames.
-        audio_config.target_playout_delay),
-      configured_encoder_bitrate_(audio_config.bitrate),
+        audio_config.target_playout_delay,
+        NewFixedCongestionControl(audio_config.bitrate)),
+      samples_sent_to_encoder_(0),
       weak_factory_(this) {
   cast_initialization_status_ = STATUS_AUDIO_UNINITIALIZED;
   VLOG(1) << "max_unacked_frames " << max_unacked_frames_;
@@ -48,8 +48,9 @@ AudioSender::AudioSender(scoped_refptr<CastEnvironment> cast_environment,
                          audio_config.frequency,
                          audio_config.bitrate,
                          audio_config.codec,
-                         base::Bind(&AudioSender::SendEncodedAudioFrame,
-                                    weak_factory_.GetWeakPtr())));
+                         base::Bind(&FrameSender::SendEncodedFrame,
+                                    weak_factory_.GetWeakPtr(),
+                                    audio_config.bitrate)));
     cast_initialization_status_ = audio_encoder_->InitializationResult();
   } else {
     NOTREACHED();  // No support for external audio encoding.
@@ -89,142 +90,17 @@ void AudioSender::InsertAudio(scoped_ptr<AudioBus> audio_bus,
     return;
   }
 
-  audio_encoder_->InsertAudio(audio_bus.Pass(), recorded_time);
-}
-
-void AudioSender::SendEncodedAudioFrame(
-    scoped_ptr<EncodedFrame> encoded_frame) {
-  DCHECK(cast_environment_->CurrentlyOn(CastEnvironment::MAIN));
-
-  const uint32 frame_id = encoded_frame->frame_id;
-
-  const bool is_first_frame_to_be_sent = last_send_time_.is_null();
-  last_send_time_ = cast_environment_->Clock()->NowTicks();
-  last_sent_frame_id_ = frame_id;
-  // If this is the first frame about to be sent, fake the value of
-  // |latest_acked_frame_id_| to indicate the receiver starts out all caught up.
-  // Also, schedule the periodic frame re-send checks.
-  if (is_first_frame_to_be_sent) {
-    latest_acked_frame_id_ = frame_id - 1;
-    ScheduleNextResendCheck();
-  }
-
-  cast_environment_->Logging()->InsertEncodedFrameEvent(
-      last_send_time_, FRAME_ENCODED, AUDIO_EVENT, encoded_frame->rtp_timestamp,
-      frame_id, static_cast<int>(encoded_frame->data.size()),
-      encoded_frame->dependency == EncodedFrame::KEY,
-      configured_encoder_bitrate_);
-
-  RecordLatestFrameTimestamps(frame_id,
-                              encoded_frame->reference_time,
-                              encoded_frame->rtp_timestamp);
-
-  // At the start of the session, it's important to send reports before each
-  // frame so that the receiver can properly compute playout times.  The reason
-  // more than one report is sent is because transmission is not guaranteed,
-  // only best effort, so we send enough that one should almost certainly get
-  // through.
-  if (num_aggressive_rtcp_reports_sent_ < kNumAggressiveReportsSentAtStart) {
-    // SendRtcpReport() will schedule future reports to be made if this is the
-    // last "aggressive report."
-    ++num_aggressive_rtcp_reports_sent_;
-    const bool is_last_aggressive_report =
-        (num_aggressive_rtcp_reports_sent_ == kNumAggressiveReportsSentAtStart);
-    VLOG_IF(1, is_last_aggressive_report) << "Sending last aggressive report.";
-    SendRtcpReport(is_last_aggressive_report);
-  }
-
-  if (send_target_playout_delay_) {
-    encoded_frame->new_playout_delay_ms =
-        target_playout_delay_.InMilliseconds();
-  }
-  transport_sender_->InsertFrame(ssrc_, *encoded_frame);
-}
+  int64 old_frames_sent =
+      samples_sent_to_encoder_ * kAudioFrameRate / rtp_timebase_;
+  samples_sent_to_encoder_ += audio_bus->frames();
+  int64 new_frames_sent =
+      samples_sent_to_encoder_ * kAudioFrameRate / rtp_timebase_;
+  frames_in_encoder_ += new_frames_sent - old_frames_sent;
 
-void AudioSender::OnReceivedCastFeedback(const RtcpCastMessage& cast_feedback) {
-  DCHECK(cast_environment_->CurrentlyOn(CastEnvironment::MAIN));
-
-  if (is_rtt_available()) {
-    // 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();
-    }
-  }
-
-  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()) {
-    // We only count duplicate ACKs when we have sent newer frames.
-    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;
-  }
-
-  cast_environment_->Logging()->InsertFrameEvent(
-      cast_environment_->Clock()->NowTicks(),
-      FRAME_ACK_RECEIVED,
-      AUDIO_EVENT,
-      GetRecordedRtpTimestamp(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 -
-                             latest_acked_frame_id_) < 0;
-  VLOG(2) << "Received ACK" << (is_acked_out_of_order ? " out-of-order" : "")
-          << " for frame " << cast_feedback.ack_frame_id;
-  if (!is_acked_out_of_order) {
-    // Cancel resends of acked frames.
-    std::vector<uint32> cancel_sending_frames;
-    while (latest_acked_frame_id_ != cast_feedback.ack_frame_id) {
-      latest_acked_frame_id_++;
-      cancel_sending_frames.push_back(latest_acked_frame_id_);
-    }
-    transport_sender_->CancelSendingFrames(ssrc_, cancel_sending_frames);
-    latest_acked_frame_id_ = cast_feedback.ack_frame_id;
-  }
+  audio_encoder_->InsertAudio(audio_bus.Pass(), recorded_time);
 }
 
-bool AudioSender::ShouldDropNextFrame(base::TimeTicks capture_time) const {
-  DCHECK(cast_environment_->CurrentlyOn(CastEnvironment::MAIN));
-  int frames_in_flight = 0;
-  base::TimeDelta duration_in_flight;
-  if (!last_send_time_.is_null()) {
-    frames_in_flight =
-        static_cast<int32>(last_sent_frame_id_ - latest_acked_frame_id_);
-    if (frames_in_flight > 0) {
-      const uint32 oldest_unacked_frame_id = latest_acked_frame_id_ + 1;
-      duration_in_flight =
-          capture_time - GetRecordedReferenceTime(oldest_unacked_frame_id);
-    }
-  }
-  VLOG(2) << frames_in_flight
-          << " frames in flight; last sent: " << last_sent_frame_id_
-          << "; latest acked: " << latest_acked_frame_id_
-          << "; duration in flight: "
-          << duration_in_flight.InMicroseconds() << " usec ("
-          << (target_playout_delay_ > base::TimeDelta() ?
-                  100 * duration_in_flight / target_playout_delay_ :
-                  kint64max) << "%)";
-  return frames_in_flight >= max_unacked_frames_ ||
-      duration_in_flight >= target_playout_delay_;
+void AudioSender::OnAck(uint32 frame_id) {
 }
 
 }  // namespace cast