dnl The given libavcodec wasn't built with --enable-pp
AC_MSG_RESULT(no)
AC_MSG_ERROR([${real_ffmpeg_tree}/libavcodec/libavcodec.a was not compiled with postprocessing support, make sure you configured ffmpeg with --enable-pp])
AC_MSG_ERROR([cannot find libpostproc.a in ${real_ffmpeg_tree}/[libavcodec/]libpostproc/. Make sure you configured ffmpeg with --enable-pp])