iOS HW H264 support.

talk/media/base/constants.cc

 /*
  * libjingle
  * Copyright 2012 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 110 matching lines @@
 
 const int kRtpVideoRotationHeaderExtensionDefaultId = 4;
 const char kRtpVideoRotationHeaderExtension[] = "urn:3gpp:video-orientation";
 const char kRtpVideoRotation6BitsHeaderExtensionForTesting[] =
     "urn:3gpp:video-orientation:6";
 
 const int kNumDefaultUnsignalledVideoRecvStreams = 0;
 
 const char kVp8CodecName[] = "VP8";
 const char kVp9CodecName[] = "VP9";
+const char kH264CodecName[] = "H264";
 
 const int kDefaultVp8PlType = 100;
 const int kDefaultVp9PlType = 101;
+// Matches VCM_H264_PAYLOAD_TYPE in video_coding_defines.h.

[pbos-webrtc, 2015/06/25 20:20:14]

Does this line matter? Also have you made sure that this doesn't overlap with
any other payload types?

[tkchin_webrtc, 2015/06/25 21:37:49]

Apparently not - why is pltype defined in two places then?
No, I'd assumed that they should match. You should tell me what I should be
using here - I don't know the ranges for payload types  - a comment in
videoengine2.cc says 120-127 is reserved for external factories, so this should
probably be something else. 104 seems to work fine.

[pbos-webrtc, 2015/06/26 05:28:31]

Legacy reasons I think, not sure.
I believe you should pick something not used here nor for
talk/media/webrtc/webrtcvoiceengine.cc ( yes, more than one place defines these
:( ). 104 is default for 32k ISAC, 107 looks free. I hope there's no third
place.

I don't like it. https://www.youtube.com/watch?v=OP7H2fMdfqk

+const int kDefaultH264PlType = 127;
 const int kDefaultRedPlType = 116;
 const int kDefaultUlpfecType = 117;
 const int kDefaultRtxVp8PlType = 96;
 
 const int kDefaultVideoMaxWidth = 640;
 const int kDefaultVideoMaxHeight = 400;
 const int kDefaultVideoMaxFramerate = 30;
 }  // namespace cricket