Disable denoising for VP9 by default.

talk/media/webrtc/webrtcvideoengine2.cc

 /*
  * libjingle
  * Copyright 2014 Google Inc.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
  *
  *  1. Redistributions of source code must retain the above copyright notice,
  *     this list of conditions and the following disclaimer.
  *  2. Redistributions in binary form must reproduce the above copyright notice,
@@ skipping 465 matching lines @@
 
 void* WebRtcVideoChannel2::WebRtcVideoSendStream::ConfigureVideoEncoderSettings(
     const VideoCodec& codec,
     const VideoOptions& options,
     bool is_screencast) {
   // No automatic resizing when using simulcast or screencast.
   bool automatic_resize =
       !is_screencast && parameters_.config.rtp.ssrcs.size() == 1;
   bool frame_dropping = !is_screencast;
   bool denoising;
+  bool codec_default_denoising = false;
   if (is_screencast) {
     denoising = false;
   } else {
-    options.video_noise_reduction.Get(&denoising);
+    // Use codec default if video_noise_reduction is unset.
+    codec_default_denoising = !options.video_noise_reduction.Get(&denoising);
   }
 
   if (CodecNamesEq(codec.name, kVp8CodecName)) {
     encoder_settings_.vp8 = webrtc::VideoEncoder::GetDefaultVp8Settings();
     encoder_settings_.vp8.automaticResizeOn = automatic_resize;
-    encoder_settings_.vp8.denoisingOn = denoising;
+    // VP8 denoising is enabled by default.
+    encoder_settings_.vp8.denoisingOn =
+        codec_default_denoising ? true : denoising;
     encoder_settings_.vp8.frameDroppingOn = frame_dropping;
     return &encoder_settings_.vp8;
   }
   if (CodecNamesEq(codec.name, kVp9CodecName)) {
     encoder_settings_.vp9 = webrtc::VideoEncoder::GetDefaultVp9Settings();
-    encoder_settings_.vp9.denoisingOn = denoising;
+    // VP9 denoising is disabled by default.
+    encoder_settings_.vp9.denoisingOn =
+        codec_default_denoising ? false : denoising;
     encoder_settings_.vp9.frameDroppingOn = frame_dropping;
     return &encoder_settings_.vp9;
   }
   return NULL;
 }
 
 DefaultUnsignalledSsrcHandler::DefaultUnsignalledSsrcHandler()
     : default_recv_ssrc_(0), default_renderer_(NULL) {}
 
 UnsignalledSsrcHandler::Action DefaultUnsignalledSsrcHandler::OnUnsignalledSsrc(
@@ skipping 262 matching lines @@
   rtcp_receiver_report_ssrc_ = kDefaultRtcpReceiverReportSsrc;
   sending_ = false;
   default_send_ssrc_ = 0;
   SetRecvCodecs(recv_codecs);
 }
 
 void WebRtcVideoChannel2::SetDefaultOptions() {
   options_.cpu_overuse_detection.Set(true);
   options_.dscp.Set(false);
   options_.suspend_below_min_bitrate.Set(false);
-  options_.video_noise_reduction.Set(true);
   options_.screencast_min_bitrate.Set(0);
 }
 
 WebRtcVideoChannel2::~WebRtcVideoChannel2() {
   for (auto& kv : send_streams_)
     delete kv.second;
   for (auto& kv : receive_streams_)
     delete kv.second;
 }
 
@@ skipping 1949 matching lines @@
       video_codecs[i].rtx_payload_type = rtx_mapping[video_codecs[i].codec.id];
     }
   }
 
   return video_codecs;
 }
 
 }  // namespace cricket
 
 #endif  // HAVE_WEBRTC_VIDEO