iOS将CAF文件转换为MP3----lame编译篇

开篇语：

现在很多项目都加入了语音功能，可是iOS录音格式是caf，这导致音频文件很难在PC和Android端无缝播放，为了解决此问题，我们需要选择一种所有平台都能播放的格式：mp3 。iOS端要想完成转换，还得靠lame啊。好了，在使用它之前，先看看如何编译吧！

编译：

先找个地方下载源码：官网下载地址 如果下载慢的话，可以下载优快云资源：lame 3.100 ，压缩包不大 6M多点。然后就是我们的编译文件了：

build-lame-framework.sh  和lame源码放在同一个路径即可。直接生成lame.framework，是不是很方便~

#!/bin/sh

CONFIGURE_FLAGS="--disable-shared --disable-frontend"

ARCHS="arm64 armv7s armv7 x86_64"  #i386

# directories
SOURCE="lame-3.100"
FAT=".fat-lame"

SCRATCH=".scratch-lame"
# must be an absolute path
THIN=`pwd`/".thin-lame"

COMPILE="y"
LIPO="y"
FRAMEWORK="y"

if [ "$*" ]
then
	if [ "$*" = "lipo" ]
	then
		# skip compile
		COMPILE=
	else
		ARCHS="$*"
		if [ $# -eq 1 ]
		then
			# skip lipo
			LIPO=
		fi
	fi
fi

if [ "$COMPILE" ]
then
	CWD=`pwd`
	for ARCH in $ARCHS
	do
		echo "building $ARCH..."
		mkdir -p "$SCRATCH/$ARCH"
		cd "$SCRATCH/$ARCH"

		if [ "$ARCH" = "i386" -o "$ARCH" = "x86_64" ]
		then
		    PLATFORM="iPhoneSimulator"
		    if [ "$ARCH" = "x86_64" ]
		    then
		    	SIMULATOR="-mios-simulator-version-min=7.0"
                        HOST=x86_64-apple-darwin
		    else
		    	SIMULATOR="-mios-simulator-version-min=5.0"
                        HOST=i386-apple-darwin
		    fi
		else
		    PLATFORM="iPhoneOS"
		    SIMULATOR=
                    HOST=arm-apple-darwin
		fi

		XCRUN_SDK=`echo $PLATFORM | tr '[:upper:]' '[:lower:]'`
		CC="xcrun -sdk $XCRUN_SDK clang -arch $ARCH"
		#AS="$CWD/$SOURCE/extras/gas-preprocessor.pl $CC"
		CFLAGS="-arch $ARCH $SIMULATOR -fembed-bitcode"
		CXXFLAGS="$CFLAGS"
		LDFLAGS="$CFLAGS"

		CC=$CC $CWD/$SOURCE/configure \
		    $CONFIGURE_FLAGS \
                    --host=$HOST \
		    --prefix="$THIN/$ARCH" \
                    CC="$CC" CFLAGS="$CFLAGS" LDFLAGS="$LDFLAGS"

		make -j3 install
		cd $CWD
	done
fi

if [ "$LIPO" ]
then
	echo "building fat binaries..."
	mkdir -p $FAT/lib
	set - $ARCHS
	CWD=`pwd`
	cd $THIN/$1/lib
	for LIB in *.a
	do
		cd $CWD
		lipo -create `find $THIN -name $LIB` -output $FAT/lib/$LIB
	done

	cd $CWD
	cp -rf $THIN/$1/include $FAT
fi

if [ "$FRAMEWORK" ]
then
	rm -rf lame.framework
	echo "building lame.framework..."
	mkdir -p lame.framework/Headers/
	cp -rf $FAT/include/lame/* lame.framework/Headers/
	cp -f $FAT/lib/libmp3lame.a lame.framework/lame
fi

#   clean tmp directories
rm -rf $SOURCE $FAT $SCRATCH $THIN

执行方法：

./build-lame-framework.sh

附上已经编译好的文件：lame.framework  支持 arm64、armv7s、armv7、x86_64

到此为止，前期工作已经准备完毕，下一篇文章，让我将结束lame的简单使用方法。