Increase maximum number of B-frames, necessary for H.264 encoding.

patch by Erik Slagter, erik at slagter .... name

Originally committed as revision 5039 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavcodec/avcodec.h

@@ -324,7 +324,7 @@ typedef struct RcOverride{
 /* only for ME compatiblity with old apps */
 extern int motion_estimation_method;
 
-#define FF_MAX_B_FRAMES 8
+#define FF_MAX_B_FRAMES 16
 
 /* encoding support
    these flags can be passed in AVCodecContext.flags before initing