API changes, most recent first:
+2020-xx-xx - xxxxxxxxxx - lavc 58.114.100 - avcodec.h
+ Deprecate AVCodecContext.thread_safe_callbacks. Starting with
+ LIBAVCODEC_VERSION_MAJOR=60, user callbacks must always be
+ thread-safe when frame threading is used.
+
2020-11-25 - xxxxxxxxxx - lavc 58.113.100 - avcodec.h
Adds a new flag AV_CODEC_EXPORT_DATA_FILM_GRAIN for export_side_data.