在32位的Ubuntu 11.04中为Android NDK r6编译FFmpeg0.10.1版Android中使用FFmpeg媒体库

1：编译过程中所遇到问题以及解决方式

编译方法原则：

1. FFmpeg  的源代码不能做任何改动；
2. FFmpeg  的配置可以根据需要改变； 
3. 用脚本配置

Update for ndk-r6:      

Note that you may need to create ./android/armv7-a/ folder in the ffmpeg directory yourself .

如果你是再ndk-r6情况下这步是必须的。

相关文件：

config.sh

#!/bin/bash
######################################################
# 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 $OPTIMIZE_CFLAGS 
# call build_one
######################################################
#change these three lines if you want to build using different vesion of Android ndk
#build_one is for ndk 5, and build_one_r6 is for ndk 6
NDK=~/ffmpeg/android-ndk-r6
PLATFORM=$NDK/platforms/android-8/arch-arm/
PREBUILT=$NDK/toolchains/arm-linux-androideabi-4.4.3/prebuilt/linux-x86
function build_one_r6
{
./configure \
    --disable-shared \
    --enable-static \
    --enable-gpl \
    --enable-version3 \
    --enable-nonfree \
    --disable-doc \
    --disable-ffmpeg \
    --disable-ffplay \
    --disable-ffprobe \
    --disable-ffserver \
    --disable-avdevice \
    --disable-avfilter \
    --disable-postproc \
    --enable-small \
    --cross-prefix=$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-once  --dynamic-linker=/system/bin/linker $PREBUILT/lib/gcc/arm-linux-androideabi/4.4.3/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-once  --dynamic-linker=/system/bin/linker $PREBUILT/lib/gcc/arm-linux-androideabi/4.4.3/libgcc.a
}
#arm v6
#CPU=armv6
#OPTIMIZE_CFLAGS="-marm -march=$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/$CPU
ADDITIONAL_CONFIGURE_FLAG=
#build_one
build_one_r6
#arm v7vfp
#CPU=armv7-a
#OPTIMIZE_CFLAGS="-mfloat-abi=softfp -mfpu=vfp -marm -march=$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

创建一个Android.mk文件，放在 /root/develop/workspace/jni目录
内容参考Android.mk 

开始编译.  这个过程需要几分钟，耐心等待吧。

尽量别去修改ffmpeg本身源代码去处理错误，以免后期用到某些功能点是出现不可避免的错误　　

编译完成!
Compile arm    : ffmpeg <= vc1test.c
Compile arm    : ffmpeg <= vc1testenc.c
Compile arm    : ffmpeg <= voc.c
Compile arm    : ffmpeg <= vocdec.c
Compile arm    : ffmpeg <= vocenc.c
Compile arm    : ffmpeg <= vorbiscomment.c
Compile arm    : ffmpeg <= vqf.c
Compile arm    : ffmpeg <= wav.c
Compile arm    : ffmpeg <= wc3movie.c
Compile arm    : ffmpeg <= westwood.c
Compile arm    : ffmpeg <= wtv.c
Compile arm    : ffmpeg <= wtvdec.c
Compile arm    : ffmpeg <= wv.c
Compile arm    : ffmpeg <= xa.c
Compile arm    : ffmpeg <= xwma.c
Compile arm    : ffmpeg <= yop.c
Compile arm    : ffmpeg <= yuv4mpeg.c
SharedLibrary  : libffmpeg.so
Install        : libffmpeg.so => libs/armeabi/libffmpeg.so