commit 0429f78992f7395e7785c46bf29dafd575d4c113
author Sebastian Jansson <srte@webrtc.org> Thu Oct 03 16:32:45 2019
committer Commit Bot <commit-bot@chromium.org> Thu Oct 03 17:38:22 2019
tree 94ecc179049a85fd3e44a045b538069fa382e305
parent 78c82a40409dc147cec33241b8af48115bfdb76f

Base overhead calculation for audio priority rate on available data.

This improves the accuracy of the priority bitrate on IPv6 networks
and when the min frame length is longer than 20 ms. Unless either of
those are true, there's no significant change in behavior.

Bug: webrtc:11001
Change-Id: I29530655cb607a8e7e8186431cd9362ca397910b
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/155521
Reviewed-by: Oskar Sundbom <ossu@webrtc.org>
Commit-Queue: Sebastian Jansson <srte@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#29375}

audio/audio_send_stream.cc

diff --git a/audio/audio_send_stream.cc b/audio/audio_send_stream.cc
index 7f14768..22bd983 100644
--- a/audio/audio_send_stream.cc
+++ b/audio/audio_send_stream.cc
@@ -877,17 +877,23 @@
   // TODO(srte): Add overhead compensation here.
   auto constraints = GetMinMaxBitrateConstraints();
 
-  DataRate max_overhead = DataRate::Zero();
+  DataRate priority_bitrate = allocation_settings_.priority_bitrate;
   if (send_side_bwe_with_overhead_) {
-    // TODO(srte): Respect |use_legacy_overhead_calculation_| here as well.
-    // OverheadPerPacket = Ipv4(20B) + UDP(8B) + SRTP(10B) + RTP(12)
-    constexpr int kOverheadPerPacket = 20 + 8 + 10 + 12;
-    const TimeDelta kMinPacketDuration = TimeDelta::ms(20);
-    max_overhead = DataSize::bytes(kOverheadPerPacket) / kMinPacketDuration;
+    if (use_legacy_overhead_calculation_) {
+      // OverheadPerPacket = Ipv4(20B) + UDP(8B) + SRTP(10B) + RTP(12)
+      constexpr int kOverheadPerPacket = 20 + 8 + 10 + 12;
+      const TimeDelta kMinPacketDuration = TimeDelta::ms(20);
+      DataRate max_overhead =
+          DataSize::bytes(kOverheadPerPacket) / kMinPacketDuration;
+      priority_bitrate += max_overhead;
+    } else {
+      RTC_DCHECK(frame_length_range_);
+      const DataSize kOverheadPerPacket =
+          DataSize::bytes(total_packet_overhead_bytes_);
+      DataRate max_overhead = kOverheadPerPacket / frame_length_range_->first;
+      priority_bitrate += max_overhead;
+    }
   }
-  DataRate priority_bitrate =
-      allocation_settings_.priority_bitrate + max_overhead;
-
   if (allocation_settings_.priority_bitrate_raw)
     priority_bitrate = *allocation_settings_.priority_bitrate_raw;