OpenCV 是英特尔开源的跨平台计算机视觉库。也就是说，它是一套包含从图像预处理到预训练模型调用等大量视觉 API 的库，并可以处理图像识别、目标检测、图像分割和行人再识别等主流视觉任务。
opencv4 的主要更新如下
After almost 3.5 years since groundbreaking 3.0 release, we are glad to present the first stable release in the 4.x line.
Release highlights:
OpenCV is now C++11 library and requires C++11-compliant compiler. Minimum required CMake version has been raised to 3.5.1.
A lot of C API from OpenCV 1.x has been removed.
Persistence (storing and loading structured data to/from XML, YAML or JSON) in the core module has been completely reimplemented in C++ and lost the C API as well.
New module G-API has been added, it acts as an engine for very efficient graph-based image procesing pipelines.
dnn module was updated with Deep Learning Deployment Toolkit from the OpenVINO™ toolkit R4. See the guide how to build and use OpenCV with DLDT support.
dnn module now includes experimental Vulkan backend and supports networks in ONNX format.
The popular Kinect Fusion algorithm has been implemented and optimized for CPU and GPU (OpenCL)
QR code detector and decoder have been added to the objdetect module
Very efficient and yet high-quality DIS dense optical flow algorithm has been moved from opencv_contrib to the videomodule.
More details can be found in previous announces: 4.0-alpha, 4.0-beta, 4.0-rc and in the changelog
Branch 3.4 will be switched to maintanence mode: only bugfixes and light features will be accepted. BTW, release 3.4.4 is ready too!
下载安装
访问官网https://opencv.org/releases/，下载相应的安装包，我这里是windows。
下载下来是自解压安装包，解压到指定文件夹
如果没有安装多个版本的opencv，可以设置一下系统环境变量，这样就不用在新建工程时再去引用
配置引用
- vs项目属性-C/C++-附加包含目录，添加
opencv目录/build/include - 属性-链接器-常规-附加库目录，添加
opencv目录/build/x64/vc14/lib - 属性-链接器-输入-附加依赖项，添加
opencv_world430.lib - 将
opencv目录\build\x64\vc14\bin下的opencv_world430.dll放入exe目录
debug版本就是将原来lib和dll换成带d后缀的lib和dll
测试
#include <opencv2\opencv.hpp>
using namespace cv;
int main(){
Mat img; //声明一个保存图像的类
img = imread("E:\\ok.png"); //读取图像，根据图片所在位置填写路径即可
if (img.empty()) //判断图像文件是否存在
{
std::cout << "请确认图像文件名称是否正确" << std::endl;
return -1;
}
imshow("test", img); //显示图像
}
图片显示出来即配置完成