OpenCV在ubuntu下的编译安装

1 源码下载

OpenCV官网：https://opencv.org/

github地址: https://github.com/opencv/opencv/releases/tag/3.4.0

2 安装依赖

首先看官方的安装说明，这个非常有必要，官方写的比较好，基本按照官方说明进行操作就可以了。

官方编译安装说明：https://docs.opencv.org/3.4.1/d7/d9f/tutorial_linux_install.html

OpenCV必要的工具包，如下图

安装依赖

sudo apt-get install build-essential

sudo apt-get install cmake git libgtk2.0-dev pkg-config libavcodec-dev libavformat-dev libswscale-dev

sudo apt-get install python-dev python-numpy libtbb2 libtbb-dev libjpeg-dev libpng-dev libtiff-dev libjasper-dev libdc1394-22-dev

检查自己安装的gcc、cmake的版本是否太低。

3 编译安装

解压源码

tar xvzf opencv-3.4.0.tar.gz

在源码外创建一个编译文件夹，不要直接在源码文件夹里面操作，以防乱了源码，对后续开发不利

mkdir build

进入创建的文件夹

cd build/

执行cmake，生成makefile

cmake ../opencv-3.4.0 -DWITH_GTK_2_X=ON -DCMAKE_INSTALL_PREFIX=/usr/local

编译

make

安装

sudo make install

查看安装结果

pkg-config --cflags --libs opencv

4 配置

安装完后配置

sudo gedit /etc/ld.so.conf.d/opencv.conf

打开文件可能是空白的，没有关系，继续下一步，在文件末尾添加

/usr/local/lib

使配置生效

sudo ldconfig

添加环境变量

sudo gedit /etc/bash.bashrc

在文件最后添加

export PKG_CONFIG_PATH=$PKG_CONFIG_PATH:/usr/local/lib/pkgconfig

使环境变量生效

source /etc/bash.bashrc

5 例程

写一个简单的测试程序 displayImage.cpp

#include   
  
using namespace cv; 
 
int main( int argc, char** argv )  
{  
    Mat image;  
    image = imread( argv[1], 1 );  
  
    if( argc != 2 || !image.data )  
    {  
        printf( "No image data \n" );  
        return -1;  
    }  
  
    namedWindow( "Display Image", CV_WINDOW_AUTOSIZE );  
    imshow( "Display Image", image );  
    waitKey(0);  
  
    return 0;  
}

编写 CMakeLists.txt

# cmake needs this line
cmake_minimum_required(VERSION 2.8)

# Define project name
project(display_image)

# Find OpenCV, you may need to set OpenCV_DIR variable
# to the absolute path to the directory containing OpenCVConfig.cmake file
# via the command line or GUI
find_package(OpenCV REQUIRED)

# If the package has been found, several variables will
# be set, you can find the full list with descriptions
# in the OpenCVConfig.cmake file.
# Print some message showing some of them
message(STATUS "OpenCV library status:")
message(STATUS "    version: ${OpenCV_VERSION}")
message(STATUS "    libraries: ${OpenCV_LIBS}")
message(STATUS "    include path: ${OpenCV_INCLUDE_DIRS}")

if(CMAKE_VERSION VERSION_LESS "2.8.11")
  # Add OpenCV headers location to your include paths
  include_directories(${OpenCV_INCLUDE_DIRS})
endif()

# Declare the executable target built from your sources
add_executable(display_image displayImage.cpp)

# Link your application with OpenCV libraries
target_link_libraries(display_image ${OpenCV_LIBS})

执行cmake，生成makefile

cmake .

编译

make

执行

./display_image yichan.jpeg

如下图