API changes, most recent first:
+2015-09-29 - xxxxxxx - lavc 57.3.100 / lavc 57.2.0 - avcodec.h
+ Change type of AVPacket.duration from int to int64_t.
+
+2015-09-17 - xxxxxxx - lavc 57.3.100 / lavc 57.2.0 - d3d11va.h
+ Add av_d3d11va_alloc_context(). This function must from now on be used for
+ allocating AVD3D11VAContext.
+
+2015-09-15 - lavf 57.2.100 - avformat.h
+ probesize and max_analyze_duration switched to 64bit, both
+ are only accessible through AVOptions
+
2015-09-15 - lavf 57.1.100 - avformat.h
bit_rate was changed to 64bit, make sure you update any
printf() or other type sensitive code