Cast: Make vp8 3-buffer mode work

chrome/renderer/media/cast_rtp_stream.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/renderer/media/cast_rtp_stream.h"
 
 #include "base/bind.h"
 #include "base/debug/trace_event.h"
 #include "base/logging.h"
 #include "base/memory/weak_ptr.h"
@@ skipping 190 matching lines @@
       params.payload.min_bitrate * kBitrateMultiplier;
   config->max_bitrate = params.payload.max_bitrate * kBitrateMultiplier;
   if (config->min_bitrate > config->max_bitrate)
     return false;
   config->start_bitrate = config->min_bitrate;
   config->max_frame_rate = static_cast<int>(
       std::max(1.0, params.payload.max_frame_rate) + 0.5);
   if (config->max_frame_rate > 120)
     return false;
   if (params.payload.codec_name == kCodecNameVp8) {
+    config->max_number_of_video_buffers_used = 3;

[Alpha Left Google, 2014/08/25 23:23:44]

Two issues:

1. We do not want to turn on this mode by default. Maybe this should by drive by
extension. For example this can be a codec specific parameter, see here:
https://code.google.com/p/chromium/codesearch#chromium/src/chrome/common/exte...

2. This should be a boolean instead of int.

[hubbe, 2014/08/27 04:14:03]

1. Done
2. Agreed, but perhaps in a separate CL.

On 2014/08/25 23:23:44, Alpha wrote:

     config->use_external_encoder = IsHardwareVP8EncodingSupported();
     config->codec = media::cast::CODEC_VIDEO_VP8;
   } else if (params.payload.codec_name == kCodecNameH264) {
     config->use_external_encoder = IsHardwareH264EncodingSupported();
     config->codec = media::cast::CODEC_VIDEO_H264;
   } else {
     return false;
   }
   if (!config->use_external_encoder) {
     config->number_of_encode_threads = NumberOfEncodeThreads();
@@ skipping 360 matching lines @@
 void CastRtpStream::DidEncounterError(const std::string& message) {
   VLOG(1) << "CastRtpStream::DidEncounterError(" << message << ") = "
           << (IsAudio() ? "audio" : "video");
   // Save the WeakPtr first because the error callback might delete this object.
   base::WeakPtr<CastRtpStream> ptr = weak_factory_.GetWeakPtr();
   error_callback_.Run(message);
   content::RenderThread::Get()->GetMessageLoop()->PostTask(
       FROM_HERE,
       base::Bind(&CastRtpStream::Stop, ptr));
 }