适用于iOS5的FFmpeg

Question

有没有人能够使用iOS5 sdk编译ffmpeg库？我发现使用4.3 sdk的脚本但iOS5没有.我认为使用旧的sdk和armv7构建的库仍将兼容iOS 5.

这是我尝试使用的命令:

./configure \ --cc=/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/gcc \ --as='gas-preprocessor.pl /Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/gcc' \ --sysroot=/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS5.0.sdk \ --extra-ldflags=-L/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS5.0.sdk/usr/lib/system \ --target-os=darwin \ --arch=arm \ --cpu=cortex-a8 \ --extra-cflags='-arch armv7' \ --extra-ldflags='-arch armv7' \ --prefix=compiled/armv7 \ --enable-pic \ --enable-cross-compile \ --disable-armv5te \ --disable-ffmpeg \ --disable-ffplay \ --disable-ffserver \ --disable-ffprobe \ --disable-doc

我也试过使用像这样的脚本:

#!/bin/tcsh -f

if (! -d armv7) mkdir armv7
if (! -d lib) mkdir lib

rm armv7/*.a

make clean

./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' --enable-pic

make

mv libavcodec/libavcodec.a armv7/
mv libavdevice/libavdevice.a armv7/
mv libavformat/libavformat.a armv7/
mv libavutil/libavutil.a armv7/
mv libswscale/libswscale.a armv7/

rm lib/*.a

cp armv7/*.a lib/

我也尝试过切换到gcc-4.2以及llvm-gcc-4.2.但是我在评论中显示如下所示的"未知选项"错误.

任何信息都会很棒,谢谢.

Answer 1

更新:完全改变了答案,使用我使用的脚本.

你也将需要下载gas-preprocessor.pl的https://github.com/yuvi/gas-preprocessor,把它放在你的路径,并使其可执行.

然后创建一个脚本(比如说make_for_iphone.sh)并将其放入其中:

export PLATFORM="iPhoneOS"
export MIN_VERSION="4.0"
export MAX_VERSION="5.0"
export DEVROOT=/Developer/Platforms/${PLATFORM}.platform/Developer
export SDKROOT=$DEVROOT/SDKs/${PLATFORM}${MAX_VERSION}.sdk
export CC=$DEVROOT/usr/bin/llvm-gcc
export LD=$DEVROOT/usr/bin/ld
export CPP=$DEVROOT/usr/bin/cpp
export CXX=$DEVROOT/usr/bin/llvm-g++
export AR=$DEVROOT/usr/bin/ar
export LIBTOOL=$DEVROOT/usr/bin/libtool
export NM=$DEVROOT/usr/bin/nm
export CXXCPP=$DEVROOT/usr/bin/cpp
export RANLIB=$DEVROOT/usr/bin/ranlib

COMMONFLAGS="-pipe -gdwarf-2 -no-cpp-precomp -isysroot ${SDKROOT} -marm -fPIC"
export LDFLAGS="${COMMONFLAGS} -fPIC"
export CFLAGS="${COMMONFLAGS} -fvisibility=hidden"
export CXXFLAGS="${COMMONFLAGS} -fvisibility=hidden -fvisibility-inlines-hidden"

FFMPEG_LIBS="libavcodec libavdevice libavformat libavutil libswscale"

echo "Building armv6..."

make clean
./configure \
    --cpu=arm1176jzf-s \
    --extra-cflags='-arch armv6 -miphoneos-version-min=${MIN_VERSION} -mthumb' \
    --extra-ldflags='-arch armv6 -miphoneos-version-min=${MIN_VERSION}' \
    --enable-cross-compile \
    --arch=arm \
    --target-os=darwin \
    --cc=${CC} \
    --sysroot=${SDKROOT} \
    --prefix=installed \
    --disable-network \
    --disable-decoders \
    --disable-muxers \
    --disable-demuxers \
    --disable-devices \
    --disable-parsers \
    --disable-encoders \
    --disable-protocols \
    --disable-filters \
    --disable-bsfs \
    --enable-decoder=h264 \
    --enable-decoder=svq3 \
    --enable-gpl \
    --enable-pic \
    --disable-doc
perl -pi -e 's/HAVE_INLINE_ASM 1/HAVE_INLINE_ASM 0/' config.h
make -j3

mkdir -p build.armv6
for i in ${FFMPEG_LIBS}; do cp ./$i/$i.a ./build.armv6/; done

echo "Building armv7..."

make clean
./configure \
    --cpu=cortex-a8 \
    --extra-cflags='-arch armv7 -miphoneos-version-min=${MIN_VERSION} -mthumb' \
    --extra-ldflags='-arch armv7 -miphoneos-version-min=${MIN_VERSION}' \
    --enable-cross-compile \
    --arch=arm \
    --target-os=darwin \
    --cc=${CC} \
    --sysroot=${SDKROOT} \
    --prefix=installed \
    --disable-network \
    --disable-decoders \
    --disable-muxers \
    --disable-demuxers \
    --disable-devices \
    --disable-parsers \
    --disable-encoders \
    --disable-protocols \
    --disable-filters \
    --disable-bsfs \
    --enable-decoder=h264 \
    --enable-decoder=svq3 \
    --enable-gpl \
    --enable-pic \
    --disable-doc
perl -pi -e 's/HAVE_INLINE_ASM 1/HAVE_INLINE_ASM 0/' config.h
make -j3

mkdir -p build.armv7
for i in ${FFMPEG_LIBS}; do cp ./$i/$i.a ./build.armv7/; done

mkdir -p build.universal
for i in ${FFMPEG_LIBS}; do lipo -create ./build.armv7/$i.a ./build.armv6/$i.a -output ./build.universal/$i.a; done

for i in ${FFMPEG_LIBS}; do cp ./build.universal/$i.a ./$i/$i.a; done

make install

这将编译armv6和armv7版本,并使用它们将它们放入一个胖库中lipo.它将安装到您从其中运行脚本的文件夹中installed.

需要注意的是,此刻我已经过了关内联用汇编perl内联替换改变HAVE_INLINE_ASM从1到0.这是因为这个问题gas-preprocessor.pl- https://github.com/yuvi/gas-preprocessor/issues/16.

另请注意,除H264解码器外,这已关闭所有编码器,解码器,复用器,解复用器等.只需更改配置行以编译您的用例所需的内容.

请记住,这已启用GPL代码 - 因此您应该了解这对iPhone应用程序意味着什么.如果您不知道,那么您应该阅读一下.