1.FFmpeg编译

1.1.安装yasm

这里我是直接通过ubuntu包安装的,当然也可以通过编译源码来安装。

sudo apt-get install yasm

1.2.下载FFmpeg

git clone https://git.ffmpeg.org/ffmpeg.git

1.3.配置、编译FFMPEG

./configure --prefix=host --enable-shared --disable-static --disable-doc

关于FFMPEG的配置参数,我们可以通过下面命令来查看

./configure --help

然后执行

make
make install

就可以在host目录下找到我们需要的动态库和头文件了

.
├── bin
│ ├── ffmpeg
│ ├── ffprobe
│ └── ffserver
├── include
│ ├── libavcodec
│ ├── libavdevice
│ ├── libavfilter
│ ├── libavformat
│ ├── libavutil
│ ├── libswresample
│ └── libswscale
├── lib
│ ├── libavcodec.so -> libavcodec.so.57.64.101
│ ├── libavcodec.so.57 -> libavcodec.so.57.64.101
│ ├── libavcodec.so.57.64.101
│ ├── libavdevice.so -> libavdevice.so.57.1.100
│ ├── libavdevice.so.57 -> libavdevice.so.57.1.100
│ ├── libavdevice.so.57.1.100
│ ├── libavfilter.so -> libavfilter.so.6.65.100
│ ├── libavfilter.so.6 -> libavfilter.so.6.65.100
│ ├── libavfilter.so.6.65.100
│ ├── libavformat.so -> libavformat.so.57.56.101
│ ├── libavformat.so.57 -> libavformat.so.57.56.101
│ ├── libavformat.so.57.56.101
│ ├── libavutil.so -> libavutil.so.55.34.101
│ ├── libavutil.so.55 -> libavutil.so.55.34.101
│ ├── libavutil.so.55.34.101
│ ├── libswresample.so -> libswresample.so.2.3.100
│ ├── libswresample.so.2 -> libswresample.so.2.3.100
│ ├── libswresample.so.2.3.100
│ ├── libswscale.so -> libswscale.so.4.2.100
│ ├── libswscale.so.4 -> libswscale.so.4.2.100
│ ├── libswscale.so.4.2.100
│ └── pkgconfig
└── share
└── ffmpeg

2.使用FFMPEG

上面我们编译完了FFMPEG之后可以去运行以下bin目录下生成的可执行文件

~/tmp/ffmpeg/ffmpeg/host/bin$ ./ffmpeg 
./ffmpeg: error while loading shared libraries: libavdevice.so.57: cannot open shared object file: No such file or directory

发现系统提示找不到动态库,可以用

ldd ffmpeg

来查看运行当前可执行文件需要哪些动态库

~/tmp/ffmpeg/ffmpeg/host/bin$ ldd ffmpeg 
linux-vdso.so.1 => (0x00007fffcfeaf000)
libavdevice.so.57 => not found
libavfilter.so.6 => not found
libavformat.so.57 => not found
libavcodec.so.57 => not found
libswresample.so.2 => not found
libswscale.so.4 => not found
libavutil.so.55 => not found
libm.so.6 => /lib/x86_64-linux-gnu/libm.so.6 (0x00007f41d6d9e000)
libpthread.so.0 => /lib/x86_64-linux-gnu/libpthread.so.0 (0x00007f41d6b7f000)
libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007f41d67b9000)
/lib64/ld-linux-x86-64.so.2 (0x00007f41d70c7000)

应该有很多人和我一样,不想编译FFMPEG之后还要动自己系统的环境,这时有一个简单的方法可以解决这个问题。就是在当前终端export一个环境变量。

~/tmp/ffmpeg/ffmpeg/host$ export LD_LIBRARY_PATH=lib/
~/tmp/ffmpeg/ffmpeg/host/bin$ export LD_LIBRARY_PATH=../lib/
~/tmp/ffmpeg/ffmpeg/host/bin$ ldd ffmpeg
linux-vdso.so.1 => (0x00007fff25150000)
libavdevice.so.57 => ../lib/libavdevice.so.57 (0x00007f7348cc8000)
libavfilter.so.6 => ../lib/libavfilter.so.6 (0x00007f73488e8000)
libavformat.so.57 => ../lib/libavformat.so.57 (0x00007f73484cc000)
libavcodec.so.57 => ../lib/libavcodec.so.57 (0x00007f7347034000)
libswresample.so.2 => ../lib/libswresample.so.2 (0x00007f7346e17000)
libswscale.so.4 => ../lib/libswscale.so.4 (0x00007f7346b8f000)
libavutil.so.55 => ../lib/libavutil.so.55 (0x00007f7346917000)
libm.so.6 => /lib/x86_64-linux-gnu/libm.so.6 (0x00007f73465f1000)
libpthread.so.0 => /lib/x86_64-linux-gnu/libpthread.so.0 (0x00007f73463d3000)
libc.so.6 => /lib/x86_64-linux-gnu/libc.so.6 (0x00007f734600d000)
libxcb.so.1 => /usr/lib/x86_64-linux-gnu/libxcb.so.1 (0x00007f7345dee000)
libdl.so.2 => /lib/x86_64-linux-gnu/libdl.so.2 (0x00007f7345be9000)
/lib64/ld-linux-x86-64.so.2 (0x00007f7348edb000)
libXau.so.6 => /usr/lib/x86_64-linux-gnu/libXau.so.6 (0x00007f73459e5000)
libXdmcp.so.6 => /usr/lib/x86_64-linux-gnu/libXdmcp.so.6 (0x00007f73457de000)

然后再去运行上面的可执行文件就可以了

~/tmp/ffmpeg/ffmpeg/host/bin$ ./ffmpeg 
ffmpeg version n3.2.2-8-g64bb329 Copyright (c) 2000-2016 the FFmpeg developers
built with gcc 4.8 (Ubuntu 4.8.2-19ubuntu1)
configuration: --prefix=host --enable-shared --disable-static --disable-doc
libavutil 55. 34.101 / 55. 34.101
libavcodec 57. 64.101 / 57. 64.101
libavformat 57. 56.101 / 57. 56.101
libavdevice 57. 1.100 / 57. 1.100
libavfilter 6. 65.100 / 6. 65.100
libswscale 4. 2.100 / 4. 2.100
libswresample 2. 3.100 / 2. 3.100
Hyper fast Audio and Video encoder
usage: ffmpeg [options] [[infile options] -i infile]... {[outfile options] outfile}...
Use -h to get full help or, even better, run 'man ffmpeg'

3.测试程序

程序可以打印出FFmpeg类库的基本信息,使用该程序通常可以验证FFmpeg是否正确的安装配置

#include <stdio.h>  

#define __STDC_CONSTANT_MACROS

#ifdef __cplusplus
extern "C"
{
#endif
#include "libavcodec/avcodec.h"
#include "libavformat/avformat.h"
#include "libavfilter/avfilter.h"
#ifdef __cplusplus
};
#endif


/**
* AVFormat Support Information
*/
char * avformatinfo(){

char *info=(char *)malloc(40000);
memset(info,0,40000);

av_register_all();

AVInputFormat *if_temp = av_iformat_next(NULL);
AVOutputFormat *of_temp = av_oformat_next(NULL);
//Input
while(if_temp!=NULL){
sprintf(info, "%s[In ] %10s\n", info, if_temp->name);
if_temp=if_temp->next;
}
//Output
while (of_temp != NULL){
sprintf(info, "%s[Out] %10s\n", info, of_temp->name);
of_temp = of_temp->next;
}
return info;
}

/**
* AVCodec Support Information
*/
char * avcodecinfo()
{
char *info=(char *)malloc(40000);
memset(info,0,40000);

av_register_all();

AVCodec *c_temp = av_codec_next(NULL);

while(c_temp!=NULL){
if (c_temp->decode!=NULL){
sprintf(info, "%s[Dec]", info);
}
else{
sprintf(info, "%s[Enc]", info);
}
switch (c_temp->type){
case AVMEDIA_TYPE_VIDEO:
sprintf(info, "%s[Video]", info);
break;
case AVMEDIA_TYPE_AUDIO:
sprintf(info, "%s[Audio]", info);
break;
default:
sprintf(info, "%s[Other]", info);
break;
}

sprintf(info, "%s %10s\n", info, c_temp->name);

c_temp=c_temp->next;
}
return info;
}

/**
* AVFilter Support Information
*/
char * avfilterinfo()
{
char *info=(char *)malloc(40000);
memset(info,0,40000);

avfilter_register_all();

AVFilter *f_temp = (AVFilter *)avfilter_next(NULL);

while (f_temp != NULL){
sprintf(info, "%s[%15s]\n", info, f_temp->name);
f_temp=f_temp->next;
}
return info;
}

/**
* Configuration Information
*/
char * configurationinfo()
{
char *info=(char *)malloc(40000);
memset(info,0,40000);

av_register_all();

sprintf(info, "%s\n", avcodec_configuration());

return info;
}

int main(int argc, char* argv[])
{
char *infostr=NULL;
infostr=configurationinfo();
printf("\n<<Configuration>>\n%s",infostr);
free(infostr);

infostr=avformatinfo();
printf("\n<<AVFormat>>\n%s",infostr);
free(infostr);

infostr=avcodecinfo();
printf("\n<<AVCodec>>\n%s",infostr);
free(infostr);

infostr=avfilterinfo();
printf("\n<<AVFilter>>\n%s",infostr);
free(infostr);

return 0;
}

编译方法

~/tmp/ffmpeg/ffmpeg/host/test$ g++ -I ../include/ hello_world.cpp -o hello_world -L../lib/ -lavcodec -lavdevice -lavfilter -lavformat -lavutil

-I 指定头文件的搜索路径, -L指定动态库的搜索路径 -l指定要链接的动态库

这样编译出来的bin文件里面没有ffplay如果要生成ffplay需要下面两个步骤

1.编译SDL2

安装 libasound2-dev

sudo apt-get install libasound2-dev

否则可能会报下面的错误,不能播放声音

SDL_OpenAudio (2 channels, 32000 Hz): No such audio device
SDL_OpenAudio (1 channels, 32000 Hz): No such audio device
No more combinations to try, audio open failed

下载SDL2

​http://www.libsdl.org/release/SDL2-2.0.5.zip​

编译SDL2

unzip SDL2-2.0.5.zip
cd SDL2-2.0.5/
./configure --prefix=/usr/local/
make
sudo make install
2.重新配置编译FFMPEG

在执行./configure是添加 --enable-ffplay

./configure --prefix=host --enable-shared --disable-static --disable-doc --enable-ffplay
make
make install

这样就会在host/bin目录下生成ffplay了

ffplay 播放yuv视频

ffplay -pixel_format yuva444p10le -video_size 1920x1080 test.yuv

编译debug版ffmpeg

./configure --enable-debug --enable-gpl --disable-optimizations --enable-shared --enable-static --enable-ffplay --disable-x86asm --prefix=host

调试ffmpeg时,因为make install拷贝到prefix目录的动态库是不带调试信息的,可以在/etc/ld.so.conf.d目录下添加ffmpeg.conf文件然后运行sudo ldconfig

/home/cent/source/ffmpeg/libavcodec
/home/cent/source/ffmpeg/libavdevice
/home/cent/source/ffmpeg/libavfilter
/home/cent/source/ffmpeg/libavformat
/home/cent/source/ffmpeg/libavresample
/home/cent/source/ffmpeg/libavutil
/home/cent/source/ffmpeg/libpostproc
/home/cent/source/ffmpeg/libswresample
/home/cent/source/ffmpeg/libswscale