使用x264 for Android构建FFMPEG

Question

I am trying to build FFMPEG with libx264 for Android.

I can successfully build and use FFMPEG for Android but I realized that I need the ability to encode, therefore I am trying to build FFMPEG with x264.

I am using this tutorial to build FFmpeg for Android http://www.roman10.net/how-to-build-ffmpeg-for-android/

When trying to build FFMPEG I get an error:

"ERROR: libx264 not found"

And in my log it says:

"/usr/local/lib/libx264.a: could not read symbols: Archive has no index; run ranlib to add one..."

I have the latest versions of both FFMPEG and x264. I understand that FFMPEG looks for the header and libraries in usr/lib and usr/include, so in order to make it find x264 I use the cflags and ldflags:

• --extra-cflags = " -I/usr/local/include "
• --extra-ldflags = " -L/usr/local/lib "

I have tried building x264 with many different options that other people on the internet have said that i need. eg. --enable-shared, --enable-static, --disable-pthreads etc. Some forums say enable this, others say no disable that.

Any help would be much appreciated, Thanks

EDIT:

If I build FFmpeg with the simplest commands to include libx264 then it works. ie.

./configure --enable-gpl --enable-libx264 --extra-cflags="-I/usr/local/include" --extra-ldflags="-L/usr/local/lib" --enable-static --enable-shared

However I need it to work for Android. The script I am using is:

NDK=~/Desktop/android-ndk-r7
PLATFORM=$NDK/platforms/android-8/arch-arm/
PREBUILT=$NDK/toolchains/arm-linux-androideabi-4.4.3/prebuilt/darwin-x86
function build_one
{
./configure --target-os=linux \
    --prefix=$PREFIX \
    --enable-cross-compile \
    --enable-shared \
    --enable-static \
    --extra-libs="-lgcc" \
    --arch=arm \
    --cc=$PREBUILT/bin/arm-linux-androideabi-gcc \
    --cross-prefix=$PREBUILT/bin/arm-linux-androideabi- \
    --nm=$PREBUILT/bin/arm-linux-androideabi-nm \
    --sysroot=$PLATFORM \
    --extra-cflags=" -O3 -fpic -DANDROID -DHAVE_SYS_UIO_H=1 -Dipv6mr_interface=ipv6mr_ifindex -fasm -Wno-psabi -fno-short-enums -fno-strict-aliasing -finline-limit=300 $OPTIMIZE_CFLAGS -I/usr/local/include" \
    --extra-ldflags="-Wl,-rpath-link=$PLATFORM/usr/lib -L $PLATFORM/usr/lib -nostdlib -lc -lm -ldl -llog -L/usr/local/lib " \
    --enable-gpl \
    --enable-libx264 \
    --disable-everything \
    --enable-demuxer=mov \
    --enable-demuxer=h264 \
    --disable-ffplay \
    --enable-protocol=file \
    --enable-avformat \
    --enable-avcodec \
    --enable-decoder=rawvideo \
    --enable-decoder=mjpeg \
    --enable-decoder=h263 \
    --enable-decoder=mpeg4 \
    --enable-decoder=h264 \
    --enable-encoder=mjpeg \
    --enable-encoder=h263 \
    --enable-encoder=mpeg4 \
    --enable-encoder=h264 \
    --enable-parser=h264 \
    --disable-network \
    --enable-zlib \
    --disable-avfilter \
    --disable-avdevice \
    $ADDITIONAL_CONFIGURE_FLAG

make clean
make  -j4 install
$PREBUILT/bin/arm-linux-androideabi-ar d libavcodec/libavcodec.a inverse.o
$PREBUILT/bin/arm-linux-androideabi-ld -rpath-link=$PLATFORM/usr/lib -L$PLATFORM/usr/lib  -soname libffmpeg.so -shared -nostdlib  -z,noexecstack -Bsymbolic --whole-archive --no-undefined -o $PREFIX/libffmpeg.so libavcodec/libavcodec.a libavformat/libavformat.a libavutil/libavutil.a libswscale/libswscale.a -lc -lm -lz -ldl -llog  --warn-once  --dynamic-linker=/system/bin/linker $PREBUILT/lib/gcc/arm-linux-androideabi/4.4.3/libgcc.a
}

CPU=armv7-a
OPTIMIZE_CFLAGS="-mfloat-abi=softfp -mfpu=vfpv3-d16 -marm -march=$CPU "
PREFIX=./android/$CPU
ADDITIONAL_CONFIGURE_FLAG=
build_one

I am guessing that some option in my configure command is conflicting with enabling libx264

NOTE: If I remove --enable-libx264 then it works

Answer 1

I had the same problem. But after downgrading NDK to version 5c it works as described by halfninja. (ubuntu 64bit). there seem to be some changes in the toolchain from 5 to 7.

timo@serverplusplus:/tmp/android-ffmpeg-x264/Project/jni$ ndk-build 
Compile thumb  : ffmpeg <= ffmpeg.c
Compile thumb  : ffmpeg <= cmdutils.c
Executable     : ffmpeg
Install        : ffmpeg => libs/armeabi/ffmpeg
Compile thumb  : videokit <= uk_co_halfninja_videokit_Videokit.c
Compile thumb  : videokit <= ffmpeg.c
Compile thumb  : videokit <= cmdutils.c
SharedLibrary  : libvideokit.so
Install        : libvideokit.so => libs/armeabi/libvideokit.so

Answer 2

The ffmpeg source code seems to be updated, and I could compile ffmpeg with x264 for Android NDK as the following.

1 Download the halfninja's android-ffmpeg-x264 git file from https://github.com/halfninja/android-ffmpeg-x264

2 At "halfninja-android-ffmpeg-x264-fe12be0/Project/jni" directory, modify "configure_ffmpeg.sh" to link "libgcc.a" for solving a problem that can not resolve "__aeabi_f2uiz".

./configure $DEBUG_FLAG --enable-cross-compile \
--arch=arm5te \
--enable-armv5te \
--target-os=linux \
--disable-stripping \
--prefix=../output \
--disable-neon \
--enable-version3 \
--disable-shared \
--enable-static \
--enable-gpl \
--enable-memalign-hack \
--cc=arm-linux-androideabi-gcc \
--ld=arm-linux-androideabi-ld \
--extra-cflags="-fPIC -DANDROID -D__thumb__ -mthumb -Wfatal-errors -Wno-deprecated -I../x264 -Ivideokit" \
 $featureflags \
--disable-ffmpeg \
--disable-ffplay \
--disable-ffprobe \
--disable-ffserver \
--disable-network \
--enable-filter=buffer \
--enable-filter=buffersink \
--disable-demuxer=v4l \
--disable-demuxer=v4l2 \
--disable-indev=v4l \
--disable-indev=v4l2 \
--extra-ldflags="-L../x264 -L../toolchain/lib/gcc/arm-linux-androideabi/4.4.3" \
--extra-libs="-lgcc"

3 Modify "Android.mk" to link new library "libswresample.a".

FFMPEG_LIBS := $(addprefix ffmpeg/, \
 libavdevice/libavdevice.a \
 libavformat/libavformat.a \
 libavcodec/libavcodec.a \
 libavfilter/libavfilter.a \
 libswscale/libswscale.a \
 libavutil/libavutil.a \
 libswresample/libswresample.a \
 libpostproc/libpostproc.a )

4 Replace ffmpeg.c and cmdutils.c in videokit directory with ones in ffmpeg directory.

5 Follow a procedure described in README.textile.

Answer 3

I've put together a Android build system for ffmpeg+x264 here: https://github.com/guardianproject/android-ffmpeg

We're working on some wrapper Java too for running it, but that's not really usable yet.

Answer 4

These are my working flags:

x264 (a recent stable):

./configure --cross-prefix=arm-linux-androideabi- \
--enable-pic \
--enable-static \
--disable-cli \
--disable-asm \
--host=arm-linux

ffmpeg (release/0.10):

./configure --enable-cross-compile \
--arch=arm5te \
--enable-armv5te \
--target-os=linux \
--disable-stripping \
--prefix=../output \
--disable-neon \
--enable-version3 \
--disable-shared \
--enable-static \
--enable-gpl \
--enable-memalign-hack \
--cc=arm-linux-androideabi-gcc \
--ld=arm-linux-androideabi-gcc \
--extra-cflags="-fPIC -DANDROID -D__thumb__ -mthumb -Wfatal-errors -Wno-deprecated" \
--disable-everything \
--enable-decoder=h264 \
--enable-demuxer=mov \
--enable-muxer=mp4 \
--enable-encoder=libx264 \
--enable-libx264 \
--enable-protocol=file \
--enable-decoder=aac \
--enable-encoder=aac \
--disable-ffmpeg \
--disable-ffplay \
--disable-ffprobe \
--disable-ffserver \
--disable-network \
--enable-filter=buffer \
--enable-filter=buffersink \
--enable-filter=scale \
--disable-demuxer=v4l \
--disable-demuxer=v4l2 \
--disable-indev=v4l \
--disable-indev=v4l2 \
--extra-cflags="-I../x264" \
--extra-ldflags="-L../x264" \
--extra-libs="-lgcc"

Obviously you will have to adjust the paths.

Answer 5

I have met the same issue before, and I tried several times to find out the reason:

You must make sure the x264 and the ffmpeg are using same way to compile. like: using Android NDK. Using the same gcc compiler.

So you can not compile ffmpeg with this command:"--cross-prefix=$PREBUILT/darwin-x86_64/bin/arm-linux-androideabi-", but compile the x264 without that. Here is my x264 compile script:

./configure --prefix=$PREFIX \
--enable-static \
--enable-pic \
--disable-asm \
--disable-cli \
--host=arm-linux \
--cross-prefix=$PREBUILT/darwin-x86_64/bin/arm-linux-androideabi- \
--sysroot=$PLATFORM

make
sudo make install
sudo ldconfig

Answer 6

I've discovered the --enable-static option does not have any effect on ffmpeg linking behaviour for libx264. I managed to build a copy of ffmpeg with libx264 included statically by editing the config.mak after I'd run ./configure

• Build x264 from source in another directory
• Add libx264.a to EXTRALIBS line in config.mak
• Remove -lx264 from EXTRALIBS line in config.mak

Before

EXTRALIBS=-ldl -lX11 -lx264 etc.

After

EXTRALIBS=/home/adam/x264sourcebuild/libx264.a -ldl -lX11  etc.