我试过阅读很多教程。我在谷歌上花了几个小时，stackoverflow 试图回答。到目前为止，我已经阅读：尝试 在 iphone/ipad 项目和https://github.com/lajos/iFrameExtractor中使用 armv6 和 arv7 架构 FFMPEG 集成为 iPhoneOS 平台编译 FFMPEG 库。
我正在尝试为 iOS 7/Xcode 5 兼容性构建这个库，但它不起作用。我得到的一个常见错误是：
Configured with: --prefix=/Applications/Xcode.app/Contents/Developer/usr --with-gxx-include-dir=/usr/include/c++/4.2.1
yasm/nasm not found or too old. Use --disable-yasm for a crippled build.
If you think configure made a mistake, make sure you are using the latest
version from Git. If the latest version fails, report the problem to the
ffmpeg-user@ffmpeg.org mailing list or IRC #ffmpeg on irc.freenode.net.
Include the log file "config.log" produced by configure as this will help
solving the problem.
一旦完成，我也会得到更多。如：
rm: illegal option -- .
usage: rm [-f | -i] [-dPRrvW] file ...
unlink file
make: *** [clean] Error 64
我主要尝试使用此命令启动，但它总是在“make clean”时崩溃：
./configure \
--cc=/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/gcc \
--as='/usr/local/bin/gas-preprocessor.pl /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/gcc' \
--sysroot=/Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS7.0.sdk \
--target-os=darwin \
--arch=arm \
--cpu=cortex-a8 \
--extra-cflags='-arch armv7' \
--extra-ldflags='-arch armv7 -isysroot /Applications/Xcode.app/Contents/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS7.0.sdk' \
--prefix=compiled/armv7 \
--enable-cross-compile \
--enable-nonfree \
--enable-gpl \
--disable-armv5te \
--disable-swscale-alpha \
--disable-doc \
--disable-ffmpeg \
--disable-ffplay \
--disable-ffprobe \
--disable-ffserver \
--disable-asm \
--disable-debug
