OpenCV 求外接矩形以及旋转角度
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程序没有写完整，大概功能就是实现了，希望大家分享学习，把他改对
// FindRotation-angle.cpp : 定义控制台应用程序的入口点。
//
// findContours.cpp : 定义控制台应用程序的入口点。
//
#include "stdafx.h"
?
#include
#include
#include
#include
#include
#include
#pragma comment(lib,"opencv_core2410d.lib")? ? ?
#pragma comment(lib,"opencv_highgui2410d.lib")? ? ?
#pragma comment(lib,"opencv_imgproc2410d.lib")
#define PI 3.1415926
int main()
{
?// Read input binary image
?char *image_name = "test2.jpg";
?cv::Mat image = cv::imread(image_name,0);
?if (!image.data)
? return 0;
?cv::namedWindow("Binary Image");
?cv::imshow("Binary Image",image);
?
?// 从文件中加载原图?
? ? IplImage *pSrcImage = cvLoadImage(image_name, CV_LOAD_IMAGE_UNCHANGED);?
?
? ? // 转为2值图
?
? cvThreshold(pSrcImage,pSrcImage,200,255,cv::THRESH_BINARY_INV);
? ?
?
? ? image = cv::Mat(pSrcImage,true);
? ? cv::imwrite("binary.jpg",image);
?// Get the contours of the connected components
?std::vector> contours;
?cv::findContours(image,
? contours, // a vector of contours
? CV_RETR_EXTERNAL, // retrieve the external contours
? CV_CHAIN_APPROX_NONE); // retrieve all pixels of each contours
?// Print contours' length
?std::cout << "Contours: " << contours.size() << std::endl;
?std::vector>::const_iterator itContours= contours.begin();
?for ( ; itContours!=contours.end(); ++itContours)
?{
? std::cout << "Size: " << itContours->size() << std::endl;
?}
?// draw black contours on white image
?cv::Mat result(image.size(),CV_8U,cv::Scalar(255));
?cv::drawContours(result,contours,
? -1, // draw all contours
? cv::Scalar(0), // in black
? 2); // with a thickness of 2
?cv::namedWindow("Contours");
?cv::imshow("Contours",result);
?
?
?// Eliminate too short or too long contours
?int cmin= 100;? // minimum contour length
?int cmax= 1000; // maximum contour length
?std::vector>::const_iterator itc= contours.begin();
?while (itc!=contours.end()) {
? if (itc->size() < cmin || itc->size() > cmax)
? ?itc= contours.erase(itc);
? else
? ?++itc;
?}
?// draw contours on the original image
?cv::Mat original= cv::imread(image_name);
?cv::drawContours(original,contours,
? -1, // draw all contours
? cv::Scalar(255,255,0), // in white
? 2); // with a thickness of 2
?cv::namedWindow("Contours on original");
?cv::imshow("Contours on original",original);
?
?// Let's now draw black contours on white image
?result.setTo(cv::Scalar(255));
?cv::drawContours(result,contours,
? -1, // draw all contours
? cv::Scalar(0), // in black
? 1); // with a thickness of 1
?image= cv::imread("binary.jpg",0);
?// testing the bounding box
?
?
?std::vector>::const_iterator itc_rec= contours.begin();
?while (itc_rec!=contours.end())
?{
? cv::Rect r0= cv::boundingRect(cv::Mat(*(itc_rec)));
? cv::rectangle(result,r0,cv::Scalar(0),2);
? ?++itc_rec;
?}
?
?cv::namedWindow("Some Shape descriptors");
?cv::imshow("Some Shape descriptors",result);
?CvBox2D? ? End_Rage2D;
?CvMemStorage *storage = cvCreateMemStorage(0);? //开辟内存空间
?CvSeq*? ? ? contour = NULL;? ? //CvSeq类型 存放检测到的图像轮廓边缘所有的像素值，坐标值特征的结构体以链表形式
?cvFindContours( pSrcImage, storage, &contour, sizeof(CvContour),CV_RETR_CCOMP, CV_CHAIN_APPROX_NONE);//这函数可选参数还有不少
?
?for(; contour; contour = contour->h_next)? //如果contour不为空，表示找到一个以上轮廓，这样写法只显示一个轮廓
? //如改为for(; contour; contour = contour->h_next) 就可以同时显示多个轮廓
?{?
? End_Rage2D = cvMinAreaRect2(contour);? ? //代入cvMinAreaRect2这个函数得到最小包围矩形? 这里已得出被测物体的角度，宽度,高度，和中点坐标点存放在CvBox2D类型的结构体中，主要工作基本结束。
?
?std::cout <<" angle:\n"<<(float)End_Rage2D.angle << std::endl;? ? ? //被测物体旋转角度
?
?}
?cv::waitKey();
?return 0;
}
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