ffmpeg for android build - is it complete

Question

//EDIT save time and refer to the SF project . IMO, it may save a ton of work getting up to speed.....

after more work on this issue:

added a git project

build is easier with custom toolchain installed so that you can invoke compiler the easy way

sample stdout from ndk-build

-- originally used ubuntu 12.04 inside vmplayer on windows vista. IMO linux is better for builds than cygwin.

I follow these instructions getting a indeterminant outcome in which the following conditions exist.

build_android.sh seems to exit normally
config.log has error where confirming gcc from crosstoolchain
all the static libs are built ok (./libavfilter, ./libavcodec etc )
ffmpeg.o is there and executes ok
no ./android directory as per the prefix setting to config

it looks like i can just push the binaries to my phone and test in a shell. If that's ok then i can look to a jni wrapper for the static libs.

But why didn't the build write anything to --prefix=./android/armv7-a ?? that path does not exist at the conclusion of the build

Details:

config log what was processed:

FFMPEG_CONFIGURATION='--target-os=linux --prefix=./android/armv7-a 
--enable-libvpx --enable-libvorbis --enable-pthreads --logfile=config.log
--enable-cross-compile --extra-libs=-lgcc --arch=arm 
--cc=/home/rob/src/android-ndk-r8/toolchains/arm-linux-androideabi-4.4.3/prebuilt/linux-x86/bin/arm-linux-androideabi-gcc 
--cross-prefix=/home/rob/src/android-ndk-r8/toolchains/arm-linux-androideabi-4.4.3/prebuilt/linux-x86/bin/arm-linux-androideabi- 
--nm=/home/rob/src/android-ndk-r8/toolchains/arm-linux-androideabi-4.4.3/prebuilt/linux-x86/bin/arm-linux-androideabi-nm 
--sysroot=/home/rob/src/android-ndk-r8/platforms/android-14/arch-arm/ --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 -mfloat-abi=softfp  -marm -march=armv7-a -mtune=cortex-a9 '"'"' 
--disable-shared --enable-static --extra-ldflags='"'"'
-Wl,-rpath-link=/home/rob/src/android-ndk-r8/platforms/android-14/arch-arm//usr/lib -L/home/rob/src/android-ndk-r8/platforms/android-14/arch-arm//usr/lib 
-nostdlib -lc -lm -ldl -llog'"'"' 
--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-parser=h264 --disable-network --enable-zlib --disable-avfilter --disable-avdevice'

tail of config log contains error on compiler check

zmbv_test='yes'
zmbv_test_deps='zlib'
WARNING: /home/rob/src/android-ndk-r8/toolchains/arm-linux-androideabi-4.4.3/prebuilt/linux-x86/bin/arm-linux-androideabi-pkg-config not found, library detection may fail.
mktemp -u XXXXXX
Yd2A0h
WARNING: Unknown C compiler /home/rob/src/android-ndk-r8/toolchains/arm-linux-androideabi-4.4.3/prebuilt/linux-x86/bin/arm-linux-androideabi-gcc, unable to select optimal CFLAGS
check_ld cc
check_cc
BEGIN /tmp/ffconf.m9Kg3cqt.c
    1   int main(void){ return 0; }
END /tmp/ffconf.m9Kg3cqt.c
/home/rob/src/android-ndk-r8/toolchains/arm-linux-androideabi-4.4.3/prebuilt/linux-x86/bin/arm-linux-androideabi-gcc -O3 -fpic -DANDROID -DHAVE_SYS_UIO_H=1 -Dipv6mr_interface=ipv6mr_ifindex -fasm -Wno-psabi -fno-short-enums -fno-strict-aliasing -finline-limit=300 -mfloat-abi=softfp -marm -march=armv7-a -mtune=cortex-a9 -c -o /tmp/ffconf.tO2EIBz5.o /tmp/ffconf.m9Kg3cqt.c
./configure: 640: ./configure: /home/rob/src/android-ndk-r8/toolchains/arm-linux-androideabi-4.4.3/prebuilt/linux-x86/bin/arm-linux-androideabi-gcc: not found
C compiler test failed.

tail of build_android.sh stdout looks OK

libavutil/opt.c: In function ‘av_find_opt’:
libavutil/opt.c:41:5: warning: ‘av_next_option’ is deprecated (declared at libavutil/opt.h:347) [-Wdeprecated-declarations]
CC  libavutil/pixdesc.o
libavutil/opt.c: In function ‘av_opt_set_defaults’:
libavutil/opt.c:601:5: warning: ‘av_opt_set_defaults2’ is deprecated (declared at libavutil/opt.h:370) [-Wdeprecated-declarations]
CC  libavutil/random_seed.o
CC  libavutil/rational.o
CC  libavutil/rc4.o
CC  libavutil/samplefmt.o
CC  libavutil/sha.o
CC  libavutil/timecode.o
CC  libavutil/tree.o
CC  libavutil/utils.o
CC  libavutil/x86/cpu.o
INSTALL libavdevice/avdevice.h
INSTALL presets/libvpx-1080p50_60.ffpreset
INSTALL presets/libvpx-1080p.ffpreset
INSTALL presets/libvpx-360p.ffpreset
INSTALL presets/libvpx-720p50_60.ffpreset
INSTALL presets/libvpx-720p.ffpreset
INSTALL presets/libx264-ipod320.ffpreset
INSTALL presets/libx264-ipod640.ffpreset
INSTALL doc/ffprobe.xsd
INSTALL libavdevice/libavdevice.pc
INSTALL libavfilter/asrc_abuffer.h
INSTALL libavfilter/avcodec.h
INSTALL libavfilter/avfilter.h
INSTALL libavfilter/avfiltergraph.h
INSTALL libavfilter/buffersink.h
INSTALL libavfilter/version.h
INSTALL libavfilter/vsrc_buffer.h
INSTALL libavfilter/libavfilter.pc
INSTALL libavformat/avformat.h
INSTALL libavformat/avio.h
INSTALL libavformat/version.h
INSTALL libavformat/libavformat.pc
INSTALL libavresample/avresample.h
INSTALL libavresample/version.h
INSTALL libavresample/libavresample.pc
INSTALL libavcodec/avcodec.h
INSTALL libavcodec/avfft.h
INSTALL libavcodec/dxva2.h
INSTALL libavcodec/vaapi.h
INSTALL libavcodec/vda.h
INSTALL libavcodec/vdpau.h
INSTALL libavcodec/version.h
INSTALL libavcodec/xvmc.h
INSTALL libavcodec/libavcodec.pc
INSTALL libswresample/libswresample.pc
INSTALL libswresample/swresample.h
INSTALL libswscale/swscale.h
INSTALL libswscale/libswscale.pc
INSTALL libavutil/adler32.h
INSTALL libavutil/aes.h
INSTALL libavutil/attributes.h
INSTALL libavutil/audio_fifo.h
INSTALL libavutil/audioconvert.h
INSTALL libavutil/avassert.h
INSTALL libavutil/avstring.h
INSTALL libavutil/avutil.h
INSTALL libavutil/base64.h
INSTALL libavutil/bprint.h
INSTALL libavutil/bswap.h
INSTALL libavutil/common.h
INSTALL libavutil/cpu.h
INSTALL libavutil/crc.h
INSTALL libavutil/error.h
INSTALL libavutil/eval.h
INSTALL libavutil/fifo.h
INSTALL libavutil/file.h
INSTALL libavutil/imgutils.h
INSTALL libavutil/intfloat.h
INSTALL libavutil/intfloat_readwrite.h
INSTALL libavutil/intreadwrite.h
INSTALL libavutil/lfg.h
INSTALL libavutil/log.h
INSTALL libavutil/lzo.h
INSTALL libavutil/mathematics.h
INSTALL libavutil/md5.h
INSTALL libavutil/mem.h
INSTALL libavutil/dict.h
INSTALL libavutil/opt.h
INSTALL libavutil/parseutils.h
INSTALL libavutil/pixdesc.h
INSTALL libavutil/pixfmt.h
INSTALL libavutil/random_seed.h
INSTALL libavutil/rational.h
INSTALL libavutil/samplefmt.h
INSTALL libavutil/sha.h
INSTALL libavutil/timecode.h
INSTALL libavutil/timestamp.h
INSTALL libavutil/avconfig.h
INSTALL libavutil/libavutil.pc
AR  libavdevice/libavdevice.a
AR  libavfilter/libavfilter.a
AR  libavformat/libavformat.a
AR  libavresample/libavresample.a
AR  libavcodec/libavcodec.a
AR  libswresample/libswresample.a
AR  libswscale/libswscale.a
AR  libavutil/libavutil.a
INSTALL libavdevice/libavdevice.a
INSTALL libavfilter/libavfilter.a
INSTALL libavresample/libavresample.a
INSTALL libswresample/libswresample.a
INSTALL libswscale/libswscale.a
INSTALL libavutil/libavutil.a
INSTALL libavformat/libavformat.a
LD  ffmpeg_g
INSTALL libavcodec/libavcodec.a
CP  ffmpeg
STRIP   ffmpeg
INSTALL install-progs-yes
INSTALL ffmpeg

Answer 1

The "not found" error isn't indicating that arm-linux-androideabi-gcc isn't found, that error is being returned from arm-linux-androideabi-gcc, most likely because of an erroneous flag. Since your --cross-prefix is set correctly you can remove the --cc and --nm lines. If you alter the cross-prefix slightly (take the - off the end for instance) you'll see that the not found error will change to a less ambiguous one.

Try getting rid of everything but "-DANDROID -mfloat-abi=softfp -marm -march=armv7-a" in your extra cflags, and remove the crazy extra quotation marks and see if it compiles.

Answer 2

This is what the guide you followed says:

Once the script finishes execution, there'll be a folder called android under ffmpeg-0.8 directory, which contains all the output of the build.

Answer 3

changed 2 items in the standard 'build_android.sh' to get at least output in the target directories as per $PREFIX...

abbreviated list of changes

NDK=/home/rob/src/android-ndk-r8
PLATFORM=$NDK/platforms/android-8/arch-arm/
PREBUILT=$NDK/toolchains/arm-linux-androideabi-4.4.3/prebuilt/linux-x86
export PATH=$NDK/toolchains/arm-linux-androideabi-4.4.3/prebuilt/linux-x86/bin/:$PATH

...

mkdir -p $PREFIX
..
make clean

1. export 2. create target dir

The compiler check that i complained about in the original faq is still there...

/home/rob/src/android-ndk-r8/toolchains/arm-linux-androideabi-4.4.3/prebuilt/linux-x86/bin/arm-linux-androideabi-gcc is unable to create an executable file. C compiler test failed.

But i got output binaries in the correct folder so, i'll move them to the phone and test from the CLI in a shell to see whether i can create WEBM files that will play on the phone.