我自己編譯的版本，為core2以上cpu優化
ffmpeg version N-57940-g1b3d3a9 Copyright (c) 2000-2013 the FFmpeg developers
built on Nov 6 2013 18:49:29 with gcc 4.7.3 (GCC)
configuration: --prefix=/mingw/i686-w64-mingw32 --enable-version3 --enable-gpl
--enable-nonfree --enable-avisynth --enable-libfaac --enable-libaacplus --enabl
e-libvo-aacenc --enable-libfdk-aac --enable-libmp3lame --enable-libx264 --enable
-librtmp --enable-libvpx --enable-libvorbis --enable-libopus --disable-runtime-c
pudetect --disable-doc --disable-manpages --disable-podpages --disable-txtpages
--enable-cross-compile --target-os=mingw32 --arch=x86 --enable-w32threads --extr
a-cflags='-Ofast -mtune=core2 -fomit-frame-pointer' --extra-libs='-lrtmp -lpolar
ssl -lwinmm -lws2_32 -lgdi32'
libavutil 52. 52.100 / 52. 52.100
libavcodec 55. 41.100 / 55. 41.100
libavformat 55. 21.100 / 55. 21.100
libavdevice 55. 5.100 / 55. 5.100
libavfilter 3. 90.102 / 3. 90.102
libswscale 2. 5.101 / 2. 5.101
libswresample 0. 17.104 / 0. 17.104
libpostproc 52. 3.100 / 52. 3.100