编译FFmpeg成一个SO库<转>

时间:2023-12-29 12:13:32

转帖地址:http://www.ihubin.com/blog/android-ffmpeg-demo-3/

==================================================================================

编译环境

  • Mac OS X Capitan 10.11.3
  • NDK-r10e (64-bit)
  • FFmpeg 3.0

简介

在看完了第一篇Android最简单的基于FFmpeg的例子(一)—编译FFmpeg类库的基础上再看这一篇,在前一文中,
编译FFmpeg生成了六个SO文件,如图:

编译FFmpeg成一个SO库<转>

由于数目繁多,直接使用这些类库还是比较麻烦的. 因此可以将它们合并为一个类库 libffmpeg.so .

操作步骤

前文记录的脚本不同,这个脚本不再需要修改Configure的内容(生成的是.a而不是.so,并没有涉及到版本号问题)

前文记录的脚本里面Configure的时候是“–enable-shared –disable-static”,这个脚本里面Configure的时候设置的是“–enable-static –disable-shared”。

  • 编译完成后生成的是:
    • libavcodec.a
    • libavfilter.a
    • libswresample.a
    • libavformat.a
    • libavutil.a
    • libswscale.a

该脚本运行完后,会把上述的*.a文件打包为一个so文件:

  • libffmpeg.so

合并后的类库使用起来和合并前的类库使用方法没有区别。

修改后的脚本文件为:

build_android.sh

#!/bin/bash
export TMPDIR=/Users/hubin/Desktop/ffmpeg-3.0/ffmpegtemp #这句很重要,不然会报错 unable to create temporary file in
# NDK的路径,根据自己的安装位置进行设置
NDK=~/Applications/android-sdk/ndk-bundle
# 编译针对的平台,可以根据自己的需求进行设置
# 这里选择最低支持android-, arm架构,生成的so库是放在
# libs/armeabi文件夹下的,若针对x86架构,要选择arch-x86
PLATFORM=$NDK/platforms/android-/arch-arm
# 工具链的路径,根据编译的平台不同而不同
# arm-linux-androideabi-.9与上面设置的PLATFORM对应,.9为工具的版本号,
# 根据自己安装的NDK版本来确定,一般使用最新的版本
TOOLCHAIN=$NDK/toolchains/arm-linux-androideabi-4.9/prebuilt/darwin-x86_64
function build_one
{
./configure \
--prefix=$PREFIX \
--target-os=linux \
--cross-prefix=$TOOLCHAIN/bin/arm-linux-androideabi- \
--arch=arm \
--sysroot=$PLATFORM \
--extra-cflags="-I$PLATFORM/usr/include" \
--cc=$TOOLCHAIN/bin/arm-linux-androideabi-gcc \
--nm=$TOOLCHAIN/bin/arm-linux-androideabi-nm \
--disable-shared \
--enable-runtime-cpudetect \
--enable-gpl \
--enable-small \
--enable-cross-compile \
--disable-debug \
--enable-static \
--disable-doc \
--disable-asm \
--disable-ffmpeg \
--disable-ffplay \
--disable-ffprobe \
--disable-ffserver \
--disable-postproc \
--disable-avdevice \
--disable-symver \
--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
sed -i '' 's/HAVE_CBRT 0/HAVE_CBRT 1/g' config.h
sed -i '' 's/HAVE_RINT 0/HAVE_RINT 1/g' config.h
make clean
make -j4
make install
$TOOLCHAIN/bin/arm-linux-androideabi-ld \
-rpath-link=$PLATFORM/usr/lib \
-L$PLATFORM/usr/lib \
-L$PREFIX/lib \
-soname libffmpeg.so -shared -nostdlib -Bsymbolic --whole-archive --no-undefined -o \
$PREFIX/libffmpeg.so \
libavcodec/libavcodec.a \
libavfilter/libavfilter.a \
libswresample/libswresample.a \
libavformat/libavformat.a \
libavutil/libavutil.a \
libswscale/libswscale.a \
-lc -lm -lz -ldl -llog --dynamic-linker=/system/bin/linker \
$TOOLCHAIN/lib/gcc/arm-linux-androideabi/4.9.x/libgcc.a \
}
# arm v7vfp
CPU=armv7-a
OPTIMIZE_CFLAGS="-mfloat-abi=softfp -mfpu=vfp -marm -march=$CPU "
PREFIX=./android/$CPU-vfp
ADDITIONAL_CONFIGURE_FLAG=
build_one
# CPU=armv
# PREFIX=$(pwd)/android/$CPU
# ADDI_CFLAGS="-marm"
# build_one
#arm v6
#CPU=armv6
#OPTIMIZE_CFLAGS="-marm -march=$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/$CPU
# ADDITIONAL_CONFIGURE_FLAG=
# build_one
#arm v7n
#CPU=armv7-a
#OPTIMIZE_CFLAGS="-mfloat-abi=softfp -mfpu=neon -marm -march=$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

执行build_android.sh:

1
$ chmod +x build_android.sh
1
$ ./build_android.sh

等待一会,编译成功以后就可以看到单个库版的FFmpeg了.

在 ffmpeg-3.0/android 目录下就能找到编译好的文件:

编译FFmpeg成一个SO库<转>

测试单个库版的FFmpeg

Android最简单的基于FFmpeg的例子(二)—测试编译好的SO库的基础上,稍加修改就可以.

替换src/main/jni目录中的SO文件

替换前:

编译FFmpeg成一个SO库<转>

替换后:

编译FFmpeg成一个SO库<转>

修改Android.mk文件

修改前:

LOCAL_PATH := $(call my-dir)
# FFmpeg library
include $(CLEAR_VARS)
LOCAL_MODULE := avcodec
LOCAL_SRC_FILES := libavcodec-.so
include $(PREBUILT_SHARED_LIBRARY)
include $(CLEAR_VARS)
LOCAL_MODULE := avfilter
LOCAL_SRC_FILES := libavfilter-.so
include $(PREBUILT_SHARED_LIBRARY)
include $(CLEAR_VARS)
LOCAL_MODULE := avformat
LOCAL_SRC_FILES := libavformat-.so
include $(PREBUILT_SHARED_LIBRARY)
include $(CLEAR_VARS)
LOCAL_MODULE := avutil
LOCAL_SRC_FILES := libavutil-.so
include $(PREBUILT_SHARED_LIBRARY)
include $(CLEAR_VARS)
LOCAL_MODULE := swresample
LOCAL_SRC_FILES := libswresample-.so
include $(PREBUILT_SHARED_LIBRARY)
include $(CLEAR_VARS)
LOCAL_MODULE := swscale
LOCAL_SRC_FILES := libswscale-.so
include $(PREBUILT_SHARED_LIBRARY)
# Program
include $(CLEAR_VARS)
LOCAL_MODULE := ffmpegdemo
LOCAL_SRC_FILES := ffmpegdemo.c
LOCAL_C_INCLUDES += $(LOCAL_PATH)/include
LOCAL_LDLIBS := -llog -lz
LOCAL_SHARED_LIBRARIES := avcodec avfilter avformat avutil swresample swscale
include $(BUILD_SHARED_LIBRARY)

修改后:

LOCAL_PATH := $(call my-dir)
# FFmpeg library
include $(CLEAR_VARS)
LOCAL_MODULE := ffmpeg
LOCAL_SRC_FILES := libffmpeg.so
include $(PREBUILT_SHARED_LIBRARY)
# Program
include $(CLEAR_VARS)
LOCAL_MODULE := ffmpegdemo
LOCAL_SRC_FILES := ffmpegdemo.c
LOCAL_C_INCLUDES += $(LOCAL_PATH)/include
LOCAL_LDLIBS := -llog -lz
LOCAL_SHARED_LIBRARIES := ffmpeg
include $(BUILD_SHARED_LIBRARY)

修改MainActivity.java 加载SO库的代码

修改前:

static {
System.loadLibrary("avcodec-57");
System.loadLibrary("avfilter-6");
System.loadLibrary("avformat-57");
System.loadLibrary("avutil-55");
System.loadLibrary("swresample-2");
System.loadLibrary("swscale-4");
System.loadLibrary("ffmpegdemo");
}

修改后:

static {
System.loadLibrary("ffmpeg");
System.loadLibrary("ffmpegdemo");
}

源码地址在这里

Module:FFmpeg-Single-SO

Demo APK下载地址:https://www.pgyer.com/FFmpegSingleSO

参考: