FFmpeg for iOS5

Question

Has anyone been able to compile ffmpeg libraries using the iOS5 sdk? I have found scripts that use the 4.3 sdk but nothing for iOS5. I would assume that libraries built with the old sdk and armv7 will still be compatible for iOS 5.

Here is the command I am trying to use:

./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

I have also tried using a script like this one:

#!/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/

I have also tried to switch to the gcc-4.2 as well as the llvm-gcc-4.2. However I get an "Unknown option" error shown below in the comments.

Any info will be great and thanks.

Answer 1

UPDATED: Completely changed the answer to use the script that I use.

You will also need to download gas-preprocessor.pl from https://github.com/yuvi/gas-preprocessor, put it in your path and make it executable.

Then create a script (say make_for_iphone.sh) and put this in it:

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

This compiles both armv6 and armv7 versions and puts them into a fat library using lipo. It installs to a folder underneath where you run the script from called installed.

Note that at the moment I've had to turn off inline assembly using a perl inline replace to change HAVE_INLINE_ASM from 1 to 0. This is because of this problem with gas-preprocessor.pl - https://github.com/yuvi/gas-preprocessor/issues/16.

Also note that this has turned off all encoders, decoders, muxers, demuxers, etc except for the H264 decoder. Just change the configure lines to compile what you want for your use case.

Please remember also that this has enabled GPL code - so you should be aware about what that means for iPhone apps. If you're not aware then you should do some reading about that.