[Experiment] Alpha Channel Support

modules/include/module_common_types.h

Index: modules/include/module_common_types.h
diff --git a/modules/include/module_common_types.h b/modules/include/module_common_types.h
index a75ed42fa0e7ebd42c2eb9112f9925a119362319..e8e39a88fb22dea6c6770e57ce863d6c0b40b8a3 100644
--- a/modules/include/module_common_types.h
+++ b/modules/include/module_common_types.h
@@ -37,19 +37,27 @@ struct RTPAudioHeader {
   size_t channel;                     // number of channels 2 = stereo
 };
 
-union RTPVideoTypeHeader {
-  RTPVideoHeaderVP8 VP8;
-  RTPVideoHeaderVP9 VP9;
-  RTPVideoHeaderH264 H264;
-};
-
 enum RtpVideoCodecTypes {
   kRtpVideoNone,
   kRtpVideoGeneric,
+  kRtpVideoStereo,
   kRtpVideoVp8,
   kRtpVideoVp9,
   kRtpVideoH264
 };
+
+struct RTPVideoStereoInfo {
+  RtpVideoCodecTypes stereoCodecType;
+  uint8_t frameIndex;
+  uint8_t frameCount;
+  uint64_t pictureIndex;
+};
+
+union RTPVideoTypeHeader {
+  RTPVideoHeaderVP8 VP8;
+  RTPVideoHeaderVP9 VP9;
+  RTPVideoHeaderH264 H264;
+};
 // Since RTPVideoHeader is used as a member of a union, it can't have a
 // non-trivial default constructor.
 struct RTPVideoHeader {
@@ -68,7 +76,9 @@ struct RTPVideoHeader {
                          // this frame, 0 if not using simulcast.
   RtpVideoCodecTypes codec;
   RTPVideoTypeHeader codecHeader;
+  RTPVideoStereoInfo stereoInfo;
 };
+
 union RTPTypeHeader {
   RTPAudioHeader Audio;
   RTPVideoHeader Video;