Add libvpx wrapper to media to support VP9 video decoding.

media/ffmpeg/ffmpeg_common.cc

Index: media/ffmpeg/ffmpeg_common.cc
diff --git a/media/ffmpeg/ffmpeg_common.cc b/media/ffmpeg/ffmpeg_common.cc
index 1fd5cd9991f82edbb8447f69c4e432c8102f2aca..c42104bf0beec7621524f82b4e3f5df40faf2b0b 100644
--- a/media/ffmpeg/ffmpeg_common.cc
+++ b/media/ffmpeg/ffmpeg_common.cc
@@ -10,6 +10,10 @@
 #include "media/base/video_frame.h"
 #include "media/base/video_util.h"
 
+// TODO(tomfinegan): Remove this once FFmpeg rolls for M25. The VP9 patch is in
+// tree, but this is required until the roll happens.
+#define AV_CODEC_ID_VP9 170
+
 namespace media {
 
 // Why FF_INPUT_BUFFER_PADDING_SIZE? FFmpeg assumes all input buffers are
@@ -148,6 +152,8 @@ VideoCodec CodecIDToVideoCodec(CodecID codec_id) {
       return kCodecMPEG4;
     case CODEC_ID_VP8:
       return kCodecVP8;
+    case AV_CODEC_ID_VP9:
+      return kCodecVP9;
     default:
       DVLOG(1) << "Unknown video CodecID: " << codec_id;
   }
@@ -168,6 +174,10 @@ static CodecID VideoCodecToCodecID(VideoCodec video_codec) {
       return CODEC_ID_MPEG4;
     case kCodecVP8:
       return CODEC_ID_VP8;
+    case kCodecVP9:
+      // TODO(tomfinegan): Remove this cast once FFmpeg rolls for M25, and the
+      // local define for AV_CODEC_ID_VP9 is removed.
+      return static_cast<CodecID>(AV_CODEC_ID_VP9);
     default:
       DVLOG(1) << "Unknown VideoCodec: " << video_codec;
   }
@@ -312,12 +322,21 @@ void AVStreamToVideoDecoderConfig(
 
   VideoCodec codec = CodecIDToVideoCodec(stream->codec->codec_id);
   VideoCodecProfile profile = (codec == kCodecVP8) ? VP8PROFILE_MAIN :

[scherkus (not reviewing), 2012/12/18 01:01:56]

for clarity's sake let's unfold the nested ?: operators

VideoCodecProfile profile = VIDEO_CODEC_PROFILE_UNKNOWN;
if (codec == kCodecVP8)
  profile = foo;
else if (codec == kCodecVP9)
  profile = bar;
else
  profile = ProfileIDToVideoCodecProfile(...);

[Tom Finegan, 2012/12/18 01:47:42]

Done.

-      ProfileIDToVideoCodecProfile(stream->codec->profile);
+      (codec == kCodecVP9) ? VP9PROFILE_MAIN :
+          ProfileIDToVideoCodecProfile(stream->codec->profile);
   gfx::Size natural_size = GetNaturalSize(
       visible_rect.size(), aspect_ratio.num, aspect_ratio.den);
+
+  VideoFrame::Format format = PixelFormatToVideoFormat(stream->codec->pix_fmt);
+  if (codec == kCodecVP9) {
+    // TODO(tomfinegan): libavcodec doesn't know about VP9.
+    format = VideoFrame::YV12;

[scherkus (not reviewing), 2012/12/18 01:01:56]

is this always true?

[Tom Finegan, 2012/12/18 01:47:42]

Yes: libvpx outputs either YV12 or I420. The wrapper always uses YV12, so this
is safe.

+    coded_size = natural_size;
+  }
+
   config->Initialize(codec,
                      profile,
-                     PixelFormatToVideoFormat(stream->codec->pix_fmt),
+                     format,
                      coded_size, visible_rect, natural_size,
                      stream->codec->extradata, stream->codec->extradata_size,
                      false,  // Not encrypted.