Added configurable offsets to the per-packet overhead in ANA.

webrtc/modules/audio_coding/audio_network_adaptor/bitrate_controller_unittest.cc

Index: webrtc/modules/audio_coding/audio_network_adaptor/bitrate_controller_unittest.cc
diff --git a/webrtc/modules/audio_coding/audio_network_adaptor/bitrate_controller_unittest.cc b/webrtc/modules/audio_coding/audio_network_adaptor/bitrate_controller_unittest.cc
index 9fab78101077da866dbbc28a9310befc1fb7b868..07f7061fabc8a24a83c40e7b5355ca8916d7c5ec 100644
--- a/webrtc/modules/audio_coding/audio_network_adaptor/bitrate_controller_unittest.cc
+++ b/webrtc/modules/audio_coding/audio_network_adaptor/bitrate_controller_unittest.cc
@@ -55,8 +55,8 @@ TEST(AnaBitrateControllerTest, OutputInitValueWhenTargetBitrateUnknown) {
   constexpr int kInitialBitrateBps = 32000;
   constexpr int kInitialFrameLengthMs = 20;
   constexpr size_t kOverheadBytesPerPacket = 64;
-  BitrateController controller(
-      BitrateController::Config(kInitialBitrateBps, kInitialFrameLengthMs));
+  BitrateController controller(BitrateController::Config(
+      kInitialBitrateBps, kInitialFrameLengthMs, 0, 0));

[ossu, 2017/09/14 12:16:14]

Will you be adding any tests for this functionality?

Could one (or both) of the offsets be negative? Could that push some bitrate
calculation below zero? What would happen then?

[ivoc, 2017/09/14 13:03:39]

I'm not sure if tests are the best way to check this, but some DCHECKs are
definitely a good idea to make sure the values are in the expected range. I
think typical values will be negative (real network overhead is less than our
current calculation), but they should not be negative enough to make our code
think we have negative per-packet overhead. I added DCHECKs in
bitrate_controller.cc and frame_length_controller.cc, is that okay?

   UpdateNetworkMetrics(&controller, rtc::Optional<int>(),
                        rtc::Optional<size_t>(kOverheadBytesPerPacket));
   CheckDecision(&controller, rtc::Optional<int>(kInitialFrameLengthMs * 2),
@@ -67,8 +67,8 @@ TEST(AnaBitrateControllerTest, OutputInitValueWhenOverheadUnknown) {
   constexpr int kInitialBitrateBps = 32000;
   constexpr int kInitialFrameLengthMs = 20;
   constexpr int kTargetBitrateBps = 48000;
-  BitrateController controller(
-      BitrateController::Config(kInitialBitrateBps, kInitialFrameLengthMs));
+  BitrateController controller(BitrateController::Config(
+      kInitialBitrateBps, kInitialFrameLengthMs, 0, 0));
   UpdateNetworkMetrics(&controller, rtc::Optional<int>(kTargetBitrateBps),
                        rtc::Optional<size_t>());
   CheckDecision(&controller, rtc::Optional<int>(kInitialFrameLengthMs * 2),
@@ -80,7 +80,7 @@ TEST(AnaBitrateControllerTest, ChangeBitrateOnTargetBitrateChanged) {
       "WebRTC-SendSideBwe-WithOverhead/Enabled/");
   constexpr int kInitialFrameLengthMs = 20;
   BitrateController controller(
-      BitrateController::Config(32000, kInitialFrameLengthMs));
+      BitrateController::Config(32000, kInitialFrameLengthMs, 0, 0));
   constexpr int kTargetBitrateBps = 48000;
   constexpr size_t kOverheadBytesPerPacket = 64;
   constexpr int kBitrateBps =
@@ -106,7 +106,7 @@ TEST(AnaBitrateControllerTest, UpdateMultipleNetworkMetricsAtOnce) {
       "WebRTC-SendSideBwe-WithOverhead/Enabled/");
   constexpr int kInitialFrameLengthMs = 20;
   BitrateController controller(
-      BitrateController::Config(32000, kInitialFrameLengthMs));
+      BitrateController::Config(32000, kInitialFrameLengthMs, 0, 0));
   constexpr int kTargetBitrateBps = 48000;
   constexpr size_t kOverheadBytesPerPacket = 64;
   constexpr int kBitrateBps =
@@ -127,7 +127,7 @@ TEST(AnaBitrateControllerTest, TreatUnknownFrameLengthAsFrameLengthUnchanged) {
       "WebRTC-SendSideBwe-WithOverhead/Enabled/");
   constexpr int kInitialFrameLengthMs = 20;
   BitrateController controller(
-      BitrateController::Config(32000, kInitialFrameLengthMs));
+      BitrateController::Config(32000, kInitialFrameLengthMs, 0, 0));
   constexpr int kTargetBitrateBps = 48000;
   constexpr size_t kOverheadBytesPerPacket = 64;
   constexpr int kBitrateBps =
@@ -143,7 +143,7 @@ TEST(AnaBitrateControllerTest, IncreaseBitrateOnFrameLengthIncreased) {
       "WebRTC-SendSideBwe-WithOverhead/Enabled/");
   constexpr int kInitialFrameLengthMs = 20;
   BitrateController controller(
-      BitrateController::Config(32000, kInitialFrameLengthMs));
+      BitrateController::Config(32000, kInitialFrameLengthMs, 0, 0));
 
   constexpr int kTargetBitrateBps = 48000;
   constexpr size_t kOverheadBytesPerPacket = 64;
@@ -169,7 +169,7 @@ TEST(AnaBitrateControllerTest, DecreaseBitrateOnFrameLengthDecreased) {
       "WebRTC-SendSideBwe-WithOverhead/Enabled/");
   constexpr int kInitialFrameLengthMs = 60;
   BitrateController controller(
-      BitrateController::Config(32000, kInitialFrameLengthMs));
+      BitrateController::Config(32000, kInitialFrameLengthMs, 0, 0));
 
   constexpr int kTargetBitrateBps = 48000;
   constexpr size_t kOverheadBytesPerPacket = 64;
@@ -193,7 +193,7 @@ TEST(AnaBitrateControllerTest, DecreaseBitrateOnFrameLengthDecreased) {
 TEST(AnaBitrateControllerTest, BitrateNeverBecomesNegative) {
   test::ScopedFieldTrials override_field_trials(
       "WebRTC-SendSideBwe-WithOverhead/Enabled/");
-  BitrateController controller(BitrateController::Config(32000, 20));
+  BitrateController controller(BitrateController::Config(32000, 20, 0, 0));
   constexpr size_t kOverheadBytesPerPacket = 64;
   constexpr int kFrameLengthMs = 60;
   // Set a target rate smaller than overhead rate, the bitrate is bounded by 0.
@@ -207,7 +207,7 @@ TEST(AnaBitrateControllerTest, BitrateNeverBecomesNegative) {
 TEST(AnaBitrateControllerTest, CheckBehaviorOnChangingCondition) {
   test::ScopedFieldTrials override_field_trials(
       "WebRTC-SendSideBwe-WithOverhead/Enabled/");
-  BitrateController controller(BitrateController::Config(32000, 20));
+  BitrateController controller(BitrateController::Config(32000, 20, 0, 0));
 
   // Start from an arbitrary overall bitrate.
   int overall_bitrate = 34567;