最近因为一些需求,开始学习 ffmgeg 在android 上使用.

使用的环境:

1,VMware V8 虚似机 安装的 FedoraV18 系统.(下载地址,请baidu),虚似机,最好有20-30G的空间,ndk解压占用,1.5G android-ndk-r10b

2,android-ndk32-r10b-linux-x86.tar.tar 下载地址(目前 天C 的力量,所以 http://developer.android.com/sdk/index.html 无法打开 ):

http://wear.techbrood.com/tools/sdk/ndk/index.html(据说 sdk是同步的.)

3,ffmpeg-2.6.tar.bz2

下载地址:http://ffmpeg.org/download.html#releases

4,rockplayer_ffmpeg_git_20100418.zip

rockplayer 是什么?

　　

Rockplayer受益于开源项目，也回报开源社区。

    • 1.7.0开始使用的FFmpeg库

      包含了取自git master repository的FFmpeg源码、RockPlayer使用的脚本。脚本内含详细的文档。

    • 1.7.0之前使用的FFmpeg库

      包含了FFmpeg源码，NDK需要的android.mk。请根据需要注释或放出所需要的变量组，更多说明见zip包里的readme.rockplayer。

    • ...

下载地址:http://www.rockplayer.com/download/rockplayer_ffmpeg_git_20100418.zip

　　

　　5,SSH Secure Shell Client 连接linux .(baidu SSH Secure Shell Client 下载).

感谢:

褐色狸花猫 的文章 <FFmpeg在Android上的移植之第一步>:http://blog.sina.com.cn/s/blog_69a04cf40100x1fr.html

ROMAN10 的文章 <How to Build FFmpeg for Android> :http://www.roman10.net/how-to-build-ffmpeg-for-android/

http://stackoverflow.com/questions/24853599/compiling-ffmpeg-2-3-with-android-ndk-r10

　　http://www.roman10.net/how-to-build-android-applications-based-on-ffmpeg-by-an-example/

开始:

　　1,解压 ndk.使用 tar 命令解压 android-ndk32-r10b-linux-x86.tar.tar 包 (tar --help 查看帮助) 解压到指定位置,\

　　本例中是:/home/android-ndk-r10b   .

　　2,解压 ffmpge,或 rockplayer . (unzip --help)

　　本例中是:/home/test

　　

　　3,build ffmpeg 或rockplayer .

　　3.1 ffmpeg 的 build_andriod_ffmpeg_right.sh 是:

正确sh

#!/bin/bash

######################################################

# FFmpeg builds script for Android+ARM platform

#

# This script is released under term of

#   CDDL (http://www.opensource.org/licenses/cddl1)

# Wrote by pinxue (~@gmail.com) from RockPlayer.com

#                                   2010-8 ~ 2011-4

######################################################

######################################################

# Usage:

#   put this script in top of FFmpeg source tree

#   ./build_android

#

# It generates binary for following architectures:

#     ARMv6

#     ARMv6+VFP

#     ARMv7+VFPv3-d16 (Tegra2)

#     ARMv7+Neon (Cortex-A8)

#

# Customizing:

# 1. Feel free to change ./configure parameters for more features

# 2. To adapt other ARM variants

#       set $CPU and $OPTIMIZE_CFLAGS

#       call build_one

######################################################

NDK=/home/android-ndk-r10b

PLATFORM=$NDK/platforms/android-18/arch-arm/

PREBUILT=$NDK/toolchains/arm-linux-androideabi-4.8/prebuilt/linux-x86

function build_one

{

./configure --target-os=linux \

    --prefix=$PREFIX \

    --enable-cross-compile \

    --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 " \

    --disable-shared \

    --enable-static \

    --extra-ldflags="-Wl,-rpath-link=$PLATFORM/usr/lib -L$PLATFORM/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 \

    $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-common  --dynamic-linker=/system/bin/linker $PREBUILT/lib/gcc/arm-linux-androideabi/4.8/libgcc.a

}

# arm v6

CPU=armv6

OPTIMIZE_CFLAGS="-marm -march=$CPU"

PREFIX=./android/$CPU

ADDITIONAL_CONFIGURE_FLAG=

build_one

#arm v7vfpv3

CPU=armv7-a

OPTIMIZE_CFLAGS="-mfloat-abi=softfp -mfpu=vfpv3-d16 -marm -march=$CPU "

PREFIX=./android/$CPU

ADDITIONAL_CONFIGURE_FLAG=

build_one

#arm v7vfp

CPU=armv7-a

OPTIMIZE_CFLAGS="-mfloat-abi=softfp -mfpu=vfp -marm -march=$CPU "

PREFIX=./android/$CPU-vfp

ADDITIONAL_CONFIGURE_FLAG=

build_one

#arm v7n

CPU=armv7-a

OPTIMIZE_CFLAGS="-mfloat-abi=softfp -mfpu=neon -marm -march=$CPU -mtune=cortex-a8"

PREFIX=./android/$CPU-v7n

ADDITIONAL_CONFIGURE_FLAG=--enable-neon

build_one

#arm v6+vfp

CPU=armv6

OPTIMIZE_CFLAGS="-DCMP_HAVE_VFP -mfloat-abi=softfp -mfpu=vfp -marm -march=$CPU"

PREFIX=./android/${CPU}_vfp

ADDITIONAL_CONFIGURE_FLAG=

build_one

rockplayer 的 build_andriod_rockplayer_right.sh 是:

正确sh

#!/bin/bash

######################################################

# FFmpeg builds script for Android+ARM platform

#

# This script is released under term of

#   CDDL (http://www.opensource.org/licenses/cddl1)

# Wrote by pinxue (~@gmail.com) from RockPlayer.com

#                                   2010-8 ~ 2011-4

######################################################

######################################################

# Usage:

#   put this script in top of FFmpeg source tree

#   ./build_android

#

# It generates binary for following architectures:

#     ARMv6

#     ARMv6+VFP

#     ARMv7+VFPv3-d16 (Tegra2)

#     ARMv7+Neon (Cortex-A8)

#

# Customizing:

# 1. Feel free to change ./configure parameters for more features

# 2. To adapt other ARM variants

#       set $CPU and $OPTIMIZE_CFLAGS

#       call build_one

######################################################

NDK=/home/android-ndk-r10b

PLATFORM=$NDK/platforms/android-18/arch-arm/

PREBUILT=$NDK/toolchains/arm-linux-androideabi-4.8/prebuilt/linux-x86

function build_one_r6

{

./configure \

    --disable-shared \

    --enable-static \

    --enable-gpl \

    --enable-version3 \

    --enable-nonfree \

    --disable-doc \

    --disable-ffmpeg \

    --disable-ffplay \

    --disable-ffprobe \

    --disable-ffserver \

    --disable-avdevice \

    --disable-avfilter \

    --disable-postproc \

    --enable-small \

    --cross-prefix=$PREBUILT/bin/arm-linux-androideabi- \

    --enable-cross-compile \

    --target-os=linux \

    --extra-cflags="-I$PLATFORM/usr/include" \

    --extra-ldflags="-L$PLATFORM/usr/lib -nostdlib" \

    --arch=arm \

    --disable-symver \

    --disable-debug \

    --disable-stripping \

    $ADDITIONAL_CONFIGURE_FLAG

sed -i 's/HAVE_LRINT 0/HAVE_LRINT 1/g' config.h

sed -i 's/HAVE_LRINTF 0/HAVE_LRINTF 1/g' config.h

sed -i 's/HAVE_ROUND 0/HAVE_ROUND 1/g' config.h

sed -i 's/HAVE_ROUNDF 0/HAVE_ROUNDF 1/g' config.h

sed -i 's/HAVE_TRUNC 0/HAVE_TRUNC 1/g' config.h

sed -i 's/HAVE_TRUNCF 0/HAVE_TRUNCF 1/g' config.h

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-common  --dynamic-linker=/system/bin/linker $PREBUILT/lib/gcc/arm-linux-androideabi/4.8/libgcc.a

}

function build_one_r6_2

{

$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-common  --dynamic-linker=/system/bin/linker $PREBUILT/lib/gcc/arm-linux-androideabi/4.8/libgcc.a

}

#arm armv6

CPU=armv6-a

OPTIMIZE_CFLAGS="-marm -march=$CPU"

PREFIX=./android/$CPU

ADDITIONAL_CONFIGURE_FLAG=

build_one_r6

#arm v7vfpv3

CPU=armv7-a

OPTIMIZE_CFLAGS="-mfloat-abi=softfp -mfpu=vfpv3-d16 -marm -march=$CPU "

PREFIX=./android/$CPU-vfpv3

ADDITIONAL_CONFIGURE_FLAG=

build_one_r6

#arm v7vfp

CPU=armv7-a

OPTIMIZE_CFLAGS="-mfloat-abi=softfp -mfpu=vfp -marm -march=$CPU "

PREFIX=./android/$CPU-vfp

ADDITIONAL_CONFIGURE_FLAG=

build_one_r6

#arm v7n

CPU=armv7-a

OPTIMIZE_CFLAGS="-mfloat-abi=softfp -mfpu=neon -marm -march=$CPU -mtune=cortex-a8"

PREFIX=./android/$CPU

ADDITIONAL_CONFIGURE_FLAG=--enable-neon

build_one_r6

#arm v6+vfp

CPU=armv6

OPTIMIZE_CFLAGS="-DCMP_HAVE_VFP -mfloat-abi=softfp -mfpu=vfp -marm -march=$CPU"

PREFIX=./android/${CPU}_vfp

ADDITIONAL_CONFIGURE_FLAG=

build_one_r6

#arm v7vfp

#CPU=armv7-a

#OPTIMIZE_CFLAGS="-mfloat-abi=softfp -mfpu=vfp -marm -march=$CPU "

#PREFIX=./android/$CPU-vfp

#ADDITIONAL_CONFIGURE_FLAG=

#build_one

#arm v7n

#CPU=armv7-a

#OPTIMIZE_CFLAGS="-mfloat-abi=softfp -mfpu=neon -marm -march=$CPU -mtune=cortex-a8"

#PREFIX=./android/$CPU

#ADDITIONAL_CONFIGURE_FLAG=--enable-neon

#build_one

#arm v6+vfp

#CPU=armv6

#OPTIMIZE_CFLAGS="-DCMP_HAVE_VFP -mfloat-abi=softfp -mfpu=vfp -marm -march=$CPU"

#PREFIX=./android/${CPU}_vfp

#ADDITIONAL_CONFIGURE_FLAG=

#build_one

　　将 build_andriod_rockplayer_right.sh 放入 /home/test/rockplayer 目录下.

　　将 build_andriod_ffmpeg_right.sh 放入 /home/test/ffmpeg-2.6 目录下.

　　

　　//给执行的权限

[root@localhost ffmpeg-2.6]# chmod 777 build_andriod_ffmpeg_right.sh

//执行

[root@localhost ffmpeg-2.6]# ./build_andriod_ffmpeg_right.sh

经过等待就可以见结果了.

INSTALL libavutil/libavutil.a

INSTALL doc/ffprobe.1

INSTALL doc/ffprobe-all.1

INSTALL doc/ffmpeg-utils.1

INSTALL doc/ffmpeg-scaler.1

INSTALL doc/ffmpeg-resampler.1

INSTALL doc/ffmpeg-codecs.1

INSTALL doc/ffmpeg-bitstream-filters.1

INSTALL doc/ffmpeg-formats.1

INSTALL doc/ffmpeg-protocols.1

INSTALL doc/libavutil.3

INSTALL doc/libswscale.3

INSTALL doc/libswresample.3

INSTALL doc/libavcodec.3

INSTALL doc/libavformat.3

INSTALL doc/ffprobe.1

INSTALL doc/ffprobe-all.1

INSTALL doc/ffmpeg-utils.1

INSTALL doc/ffmpeg-scaler.1

INSTALL doc/ffmpeg-resampler.1

INSTALL doc/ffmpeg-codecs.1

INSTALL doc/ffmpeg-bitstream-filters.1

INSTALL doc/ffmpeg-formats.1

INSTALL doc/ffmpeg-protocols.1

INSTALL doc/libavutil.3

INSTALL doc/libswscale.3

INSTALL doc/libswresample.3

INSTALL doc/libavcodec.3

INSTALL doc/libavformat.3

CP      ffprobe

STRIP   ffprobe

INSTALL install-progs-yes

INSTALL ffprobe

[root@localhost ffmpeg-2.6]#

编译结果:

　　在这个目录中"PREFIX=./android/$CPU ".

　　

　　

rockplayer 的so文件,比ffmpeg的so文件小了一半.

　　可以开始在android 中开整了.....-_-......

说明可能出现的错误:

Q1:PLATFORM=$NDK/platforms/android-18/arch-arm/

选择不同android对应的平台:

Q2:PREBUILT=$NDK/toolchains/arm-linux-androideabi-4.8/prebuilt/linux-x86

选择可执行的文件:

arm-linux-androideabi-4.8 这个版本要与

function build_one 中或 function build_one_r6 中

最后:

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-common --dynamic-linker=/system/bin/linker $PREBUILT/lib/gcc/arm-linux-androideabi/4.8/libgcc.a
}

这个版本相对应.

不然会报

/home/android-ndk-r10b/toolchains/arm-linux-androideabi-4.8/prebuilt/linux-x86/bin/arm-linux-androideabi-ld: error: cannot open /home/android-ndk-r10b/toolchains/arm-linux-androideabi-4.8/prebuilt/linux-x86/lib/gcc/arm-linux-androideabi/4.1/libgcc.a: No such file or directory
/home/android-ndk-r10b/toolchains/arm-linux-androideabi-4.8/prebuilt/linux-x86/bin/arm-linux-androideabi-ld: error: cannot open /home/android-ndk-r10b/toolchains/arm-linux-androideabi-4.8/prebuilt/linux-x86/lib/gcc/arm-linux-androideabi/4.1/libgcc.a: No such file or directory

libavcodec/error_resilience.c:725: error: undefined reference to '__aeabi_idivmod'

libavcodec/error_resilience.c:1177: error: undefined reference to '__aeabi_idiv'

libavcodec/error_resilience.c:1178: error: undefined reference to '__aeabi_idiv'

libavcodec/error_resilience.c:1179: error: undefined reference to '__aeabi_idiv'

libavcodec/error_resilience.c:1180: error: undefined reference to '__aeabi_idiv'

libavcodec/error_resilience.c:403: error: undefined reference to '__aeabi_idivmod'

./libavutil/mem.h:95: error: undefined reference to '__aeabi_uidiv'

./libavutil/mem.h:95: error: undefined reference to '__aeabi_uidiv'

libavcodec/error_resilience.c:220: error: undefined reference to '__aeabi_uidiv'

libavcodec/error_resilience.c:224: error: undefined reference to '__aeabi_ldivmod'

libavcodec/h263dec.c:634: error: undefined reference to '__aeabi_idivmod'

libavcodec/h264.c:466: error: undefined reference to '__aeabi_idivmod'

libavcodec/h264_ps.c:495: error: undefined reference to '__aeabi_uidiv'

libavcodec/h264_slice.c:1754: error: undefined reference to '__aeabi_uidivmod'

libavcodec/mpeg4videodec.c:2320: error: undefined reference to '__aeabi_ldivmod'

libavcodec/mpeg4videodec.c:2307: error: undefined reference to '__aeabi_ldivmod'

libavcodec/mpeg4videodec.c:2308: error: undefined reference to '__aeabi_ldivmod'

libavformat/dump.c:121: error: undefined reference to '__aeabi_uldivmod'

libavformat/dump.c:123: error: undefined reference to '__aeabi_uldivmod'

libavformat/dump.c:121: error: undefined reference to '__aeabi_uldivmod'

libavformat/dump.c:123: error: undefined reference to '__aeabi_uldivmod'

libavformat/dump.c:93: error: undefined reference to '__aeabi_l2d'

libavformat/dump.c:99: error: undefined reference to '__aeabi_l2d'

libavformat/dump.c:93: error: undefined reference to '__aeabi_l2d'

libavformat/dump.c:99: error: undefined reference to '__aeabi_l2d'

libavformat/mov.c:2517: error: undefined reference to '__aeabi_uidivmod'

libavformat/mov.c:2517: error: undefined reference to '__aeabi_uidivmod'

libavformat/utils.c:2282: error: undefined reference to '__aeabi_l2f'

libavutil/camellia.c:139: error: undefined reference to '__aeabi_llsl'

libavutil/camellia.c:139: error: undefined reference to '__aeabi_llsr'

libavutil/camellia.c:140: error: undefined reference to '__aeabi_llsl'

libavutil/camellia.c:140: error: undefined reference to '__aeabi_llsr'

libavutil/eval.c:211: error: undefined reference to '__aeabi_d2ulz'

libavutil/eval.c:211: error: undefined reference to '__aeabi_ul2d'

libavutil/eval.c:287: error: undefined reference to '__aeabi_d2lz'

libavutil/eval.c:287: error: undefined reference to '__aeabi_d2lz'

libavutil/eval.c:211: error: undefined reference to '__aeabi_d2ulz'

libavutil/eval.c:211: error: undefined reference to '__aeabi_ul2d'

libavutil/eval.c:287: error: undefined reference to '__aeabi_d2lz'

libavutil/eval.c:287: error: undefined reference to '__aeabi_d2lz'

libavutil/timecode.c:64: error: undefined reference to '__aeabi_uidivmod'

libswscale/utils.c:299: error: undefined reference to '__aeabi_llsl'

Q3:gcc is unable to create an executable file.
If gcc is a cross-compiler, use the --enable-cross-compile option.
Only do this if you know what cross compiling means.
C compiler test failed.

sh 中 gcc的路径配置出错.

"--cc=$PREBUILT/bin/arm-linux-androideabi-gcc \"

arm-linux-androideabi-gcc 是 gcc for android apk 里的一个linux可执行文件

winhex  arm-linux-androideabi-gcc 这个文件可见:

可参考: hhhbbb 的文章<elf格式分析> :http://blog.csdn.net/hhhbbb/article/details/6855004

Q4:错误error: undefined reference to 'atexit'    ,noexecstack: unknown -z option,

　　unknown  --warn-once

$PREBUILT/bin/arm-eabi-ld -rpath-link=$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 -lc -lm -lz -ldl -llog --warn-once --dynamic-linker=/system/bin/linker $PREBUILT/lib/gcc/arm-eabi/4.4.0/libgcc.a

"-z,noexecstack" 语法错误

通过 arm-eabi-ld  --help可知(可能不同的版本,命令参数不同.)

应是  -z noexecstack

--warn-once  改为 --warn-common

有问题的sh文件:

http://roman10.net/src/build_android_r6.txt

Q5:其它错误信息,怎么查看:

　　详细的错误信息: ffmpeg/config.log 可以查看

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