Extract bitrate allocation of spatial/temporal layers out of codec impl.

webrtc/video/vie_encoder.cc

Index: webrtc/video/vie_encoder.cc
diff --git a/webrtc/video/vie_encoder.cc b/webrtc/video/vie_encoder.cc
index 95a6f5a18c9f54a8139292fcfd05167cfdc8af3c..0097e823ad02edbc8dd4bcd60d7fc8bed34cea3c 100644
--- a/webrtc/video/vie_encoder.cc
+++ b/webrtc/video/vie_encoder.cc
@@ -19,6 +19,7 @@
 #include "webrtc/base/trace_event.h"
 #include "webrtc/base/timeutils.h"
 #include "webrtc/modules/pacing/paced_sender.h"
+#include "webrtc/modules/video_coding/include/video_bitrate_allocator_factory.h"
 #include "webrtc/modules/video_coding/include/video_coding.h"
 #include "webrtc/modules/video_coding/include/video_coding_defines.h"
 #include "webrtc/video/overuse_frame_detector.h"
@@ -351,6 +352,7 @@ void ViEEncoder::Stop() {
   source_proxy_->SetSource(nullptr);
   encoder_queue_.PostTask([this] {
     RTC_DCHECK_RUN_ON(&encoder_queue_);
+    rate_allocator_.reset();
     video_sender_.RegisterExternalEncoder(nullptr, settings_.payload_type,
                                           false);
     overuse_detector_.StopCheckForOveruse();
@@ -438,6 +440,8 @@ void ViEEncoder::ReconfigureEncoder() {
   codec.startBitrate = std::min(codec.startBitrate, codec.maxBitrate);
   codec.expect_encode_from_texture = last_frame_info_->is_texture;
 
+  rate_allocator_ = VideoBitrateAllocatorFactory::GetBitrateAllocator(&codec);

[perkj_webrtc, 2016/10/25 11:02:27]

This looks much better I think. 
But one more question - Do we want to move towards using VideoEncoderConfig ? 
If so, I think it might make sense have the new VideoBitrateAllocatorFactory
take that as an argument instead of VideoCodec. 

It might make sense to move VideoEncoderConfigToVideoCodec to there until
VideoSender also operate on VideoEncoderConfig or has been deprecated? 

[sprang_webrtc, 2016/10/25 11:43:03]

Hm, I'm not sure. It'll become a little messy because of how
encoder_specific_settings are handled. I might have to create a default instance
in another place just to populate the tl_factory field. Or move that out, which
brings back the codec specific part.

Can we please postpone that?

+
   bool success = video_sender_.RegisterSendCodec(
                      &codec, number_of_cores_,
                      static_cast<uint32_t>(max_data_payload_length_)) == VCM_OK;
@@ -446,17 +450,16 @@ void ViEEncoder::ReconfigureEncoder() {
     RTC_DCHECK(success);
   }
 
-  rate_allocator_.reset(new SimulcastRateAllocator(codec));
   if (stats_proxy_) {
-    stats_proxy_->OnEncoderReconfigured(encoder_config_,
-                                        rate_allocator_->GetPreferedBitrate());
+    int frame_rate = stats_proxy_->GetSendFrameRate();
+    if (frame_rate == 0)
+      frame_rate = codec.maxFramerate;
+    stats_proxy_->OnEncoderReconfigured(
+        encoder_config_, rate_allocator_->GetPreferedBitrate(frame_rate));
   }
 
   pending_encoder_reconfiguration_ = false;
-  if (stats_proxy_) {
-    stats_proxy_->OnEncoderReconfigured(encoder_config_,
-                                        rate_allocator_->GetPreferedBitrate());
-  }
+
   sink_->OnEncoderConfigurationChanged(
       std::move(streams), encoder_config_.min_transmit_bitrate_bps);
 }
@@ -679,7 +682,7 @@ void ViEEncoder::OnBitrateUpdated(uint32_t bitrate_bps,
                   << " rtt " << round_trip_time_ms;
 
   video_sender_.SetChannelParameters(bitrate_bps, fraction_lost,
-                                     round_trip_time_ms);
+                                     round_trip_time_ms, rate_allocator_.get());
 
   encoder_start_bitrate_bps_ =
       bitrate_bps != 0 ? bitrate_bps : encoder_start_bitrate_bps_;