编译FFmpeg 
cd ffmpeg

PKG_CONFIG_PATH=/usr/local/lib/pkgconfig
export PKG_CONFIG_PATH
或把上面2行加到vim~/.bash_profile
   
   
    
    source~/.bash_profile
   
   
   
   
    
    
      echo$PKG_CONFIG_PATH 
    
   
   
./configure --extra-cflags=-I/usr/local/include \
  --extra-ldflags=-L/usr/local/lib   --bindir=/usr/local/bin \
  --extra-libs="-ldl"  --enable-gpl  --enable-nonfree   --enable-libfdk_aac    --enable-libx264  --enable-shared
 
hash -r
. ~/.bash_profile