API changes, most recent first:
+2016-xx-xx - xxxxxxx - lavc 57.24.0 - avcodec.h
+ Decoders now export the frame timestamp as AVFrame.pts. It was
+ previously exported as AVFrame.pkt_pts, which is now deprecated.
+
2016-xx-xx - xxxxxxx - lavu 55.16.0 - hwcontext.h hwcontext_qsv.h
Add AV_HWDEVICE_TYPE_QSV and a new installed header with QSV-specific
hwcontext definitions.