真机编译ffmpeg

1.下载 iFrameExtractor

    git clone https://github.com/lajos/iFrameExtractor.git

2. 进入iFrameExtractor/ffmpeg, 用下面的命令编译

   ./configure --disable-doc --disable-ffmpeg --disable-ffplay --disable-ffserver --enable-cross-compile --arch=arm --target-os=darwin --cc=/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/gcc --as='gas-preprocessor/gas-preprocessor.pl /Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/gcc' --sysroot=/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS5.0.sdk --cpu=cortex-a8 --extra-cflags='-arch armv7' --extra-ldflags='-arch armv7 -isysroot/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS5.0.sdk' --enable-pic --disable-asm

3. make clean & make & make install

4. cp /usr/local/lib/*.a ./armv7/

5. 运行iFrameExtractor工程