H.264 video codec support using OpenH264/FFmpeg

webrtc/common_video/video_frame.cc

 /*
  *  Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
 #include "webrtc/video_frame.h"
 
 #include <string.h>
 
 #include <algorithm>  // swap
 
 #include "webrtc/base/bind.h"
 #include "webrtc/base/checks.h"
 
 namespace webrtc {
 
-// TODO(hbos): The FFmpeg video decoder will require up to 8 bytes, update this
-// when the FFmpeg decoder is added.
-const size_t EncodedImage::kBufferPaddingBytesH264 = 0;
+// FFmpeg's decoder, used by H264DecoderImpl, requires up to 8 bytes padding due
+// to optimized bitstream readers. See avcodec_decode_video2.
+const size_t EncodedImage::kBufferPaddingBytesH264 = 8;
 
 bool EqualPlane(const uint8_t* data1,
                 const uint8_t* data2,
                 int stride,
                 int width,
                 int height) {
   for (int y = 0; y < height; ++y) {
     if (memcmp(data1, data2, width) != 0)
       return false;
     data1 += stride;
@@ skipping 223 matching lines @@
     case kVideoCodecULPFEC:
     case kVideoCodecGeneric:
     case kVideoCodecUnknown:
       return 0;
   }
   RTC_NOTREACHED();
   return 0;
 }
 
 }  // namespace webrtc