ffmpeg 入門教程

1.在terminal，安裝ffmpeg開源庫

#brew install ffmpeg 

2.新建一個目錄first_ffmpeg，並在first_ffmpeg目錄下新建ffmpeg目錄

3.拷貝/usr/local/Cellar/ffmpeg/4.1.1/下的lib和include文件夾到上一步中的ffmpeg目錄

4.在first_ffmpeg，創建如下內容的CMakeLists.txt

cmake_minimum_required(VERSION 2.8)

project(first_ffmpeg)

include_directories("/The/path/to/first_ffmpeg/ffmpeg/include")
link_directories("/The/path/to/first_ffmpeg/ffmpeg/lib")
link_libraries(libavcodec.a)
link_libraries(libavdevice.a)
link_libraries(libavfilter.a)
link_libraries(libavformat.a)
link_libraries(libavutil.a)
link_libraries(libpostproc.a)
link_libraries(libswresample.a)
link_libraries(libswscale.a)

add_executable(${PROJECT_NAME} "main.cpp")

5.書寫main函數如下

#include <iostream>

using namespace std;

extern "C"
{
    #include "libavcodec/avcodec.h"
    #include "libavformat/avformat.h"
    #include "libswscale/swscale.h"
    #include "libavdevice/avdevice.h"
}

int main()
{
    cout << "Hello FFmpeg!" << endl;
    av_register_all();
    unsigned int version = avcodec_version();
    cout << "FFmpeg version is:" << version << endl;
    cout << "Hello World!" << endl;
    return 0;
}

6.編譯運行

#mkdir build 
#cd build
#cmake ..
#make
#./first_ffmpeg

輸出：

Hello FFmpeg!
FFmpeg version is:3810148
Hello World!

7.工程first_ffmpeg目錄結構如下

#first_ffmpeg tree -L 2

.
├── CMakeLists.txt
├── build
│   ├── CMakeCache.txt
│   ├── CMakeFiles
│   ├── Makefile
│   ├── cmake_install.cmake
│   └── first_ffmpeg
├── ffmpeg
│   ├── include
│   └── lib
└── main.cpp