linux下搭建opencv并在qt中使用
作者：vmezr
由于最近要着手做pcduino上的视频聊天的项目，从未接触过pcduino，经过讨论决定使用qt来实现。
其实qt和opencv 我都没有接触过，也打算趁机学习一下。
言归正传，首先得搭建好需要的环境，第一步是安装配置opencv，然后在qt中使用opencv的库。
（opencv的安装方法部分参考雷雨同鞋哒~）
首先，在官网/中下载opencv原码，选择linux版本进行下载。
以opencv2.4.8为例：（我用的是opencv2.4.13）
1.将压缩包解压到/usr/local/
2.直接使用sudo apt-get install cmake下载并安装cmake
3.为了方便后续摄像头捕捉等功能还需要下载opencv依赖的一些包：
apt-cache search opencv
使用此命令可以直接查到需要下载的依赖包
leo@leo-virtual-machine:/usr/local/opencv/release$ apt-cache search opencv
libcv-dev - Translation package for libcv-dev
libcv2.3 - computer vision library - libcv* translation package
libcvaux-dev - Translation package for libcvaux-dev
libcvaux2.3 - computer vision library - libcvaux translation package
libhighgui-dev - Translation package for libhighgui-dev
libhighgui2.3 - computer vision library - libhighgui translation package
libopencv-calib3d-dev - development files for libopencv-calib3d
libopencv-calib3d2.3 - computer vision Camera Calibration library
libopencv-contrib-dev - development files for libopencv-contrib
libopencv-contrib2.3 - computer vision contrib library
libopencv-core-dev - development files for libopencv-core
libopencv-core2.3 - computer vision core library
libopencv-dev - development files for opencv
libopencv-features2d-dev - development files for libopencv-features2d
libopencv-features2d2.3 - computer vision Feature Detection and Descriptor Extraction library libopencv-flann-dev - development files for libopencv-flann
libopencv-flann2.3 - computer vision Clustering and Search in Multi-Dimensional spaces library libopencv-gpu-dev - development files for libopencv-gpu
libopencv-gpu2.3 - computer vision GPU Processing library
libopencv-highgui-dev - development files for libopencv-highgui
libopencv-highgui2.3 - computer vision High-level GUI and Media I/O library
libopencv-imgproc-dev - development files for libopencv-imgproc
libopencv-imgproc2.3 - computer vision Image Processing library
libopencv-legacy-dev - development files for libopencv-legacy
libopencv-legacy2.3 - computer vision legacy library
libopencv-ml-dev - development files for libopencv-ml
libopencv-ml2.3 - computer vision Machine Learning library
libopencv-objdetect-dev - development files for libopencv-objdetect
libopencv-objdetect2.3 - computer vision Object Detection library
libopencv-video-dev - development files for libopencv-video
libopencv-video2.3 - computer vision Video analysis library
opencv-doc - OpenCV documentation and examples
python-opencv - Python bindings for the computer vision library
4.安装上述所依赖的包(sudo apt-get install xxx就ok)
5.接着就要编译opencv的原码并安装：
执行以下命令：
sudo mv opencv-2.4.8 opencv
cd opencv
mkdir release
cd release
sudo cmake -D CMAKE_BUILD_TYPE=RELEASE -D WITH_TBB=ON -D BUILD_opencv_python2=ON -D
BUILD_NEW_PYTHON_SUPPORT=ON -D
WITH_V4L=ON-DINSTALL_C_EXAMPLES=ON -D INSTALL_PYTHON_EXAMPLES=ON-DBUILD_EXAMPLES= ON -D WITH_QT=ON -D WITH_OPENGL=ON -D
WITH_VTK=ON..
注意上面命令最面的“空格..”（make编译的过程会很久~耐心等待吧）
sudo make
sudo make install（昨晚已做完这一步）
6.接着安装完成后进行配置：
添加库的路径：
sudo gedit /etc/ld.so.conf.d/opencv.conf
添加内容：
/usr/local/lib
然后输入，使设置生效：
sudo ldconfig
配置环境变量：
sudo gedit /etc/bash.bashrc
在文件最后加入以下两行并保存：
PKG_CONFIG_PATH=$PKG_CONFIG_PATH:/usr/local/lib/p kgconfig
export PKG_CONFIG_PATH
（此时opencv的安装基本完成了~~~）
7.可以测试下opencv自带测试程序：
执行以下命令：
cd /usr/local/opencv/samples/c
sudo chmod +x build_all.sh
./build_all.sh
运行：
python /usr/local/opencv/samples/python2/turing.py 会显示出如下效果图：
经过以上步骤opencv安装配置完成。
需要在qt中使用opencv只用经过非常简单的步骤：（我自己走了弯路，所以遇到很多问题不过最后解决了）只需每次在qt工程文件.pro中加入一下内容：
（在#input之前加入，第一个opencv库的位置根据自己的路径来添加，比如我是在/usr/local/include/opencv下的，有人却在/usr/include/opencv下）
INCLUDEPATH += /usr/local/include/opencv
LIBS += -lopencv_core \
-lopencv_imgproc \
-lopencv_highgui \
-lopencv_ml \
-lopencv_video \
-lopencv_features2d \
-lopencv_calib3d \
-lopencv_objdetect \
-lopencv_contrib \
-lopencv_legacy \
-lopencv_flann
然后尽管qmake，make，运行。
可以使用这样的测试程序：（1.jpg图片可自行添加）
然后：
qmake --project
修改.pro文件加入上述库的路径qmake xx.pro
make
./xx
以下是我的测试结果：
（如果编译成功就说明在qt中使用opencv成功了，如果编译出错，有可能是之前的库路径添加有误。
）
简单的安装配置就到这里了，其它的还没有学习~。