本文实例为大家分享了基于OpenCV实现图像分割的具体代码,供大家参考,具体内容如下
1、图像阈值化
源代码:
- #include "opencv2/highgui/highgui.hpp"
- #include "opencv2/imgproc/imgproc.hpp"
- #include <iostream>
- using namespace std;
- using namespace cv;
- int thresholds=50;
- int model=2;
- Mat image,srcimage;
- void track(int ,void *)
- {
- Mat result;
- threshold(srcimage,result,thresholds,255,CV_THRESH_BINARY);
- //imshow("原图",result);
- if(model==0)
- {
- threshold(srcimage,result,thresholds,255,CV_THRESH_BINARY);
- imshow("分割",result);
- }
- if(model==1)
- {
- threshold(srcimage,result,thresholds,255,THRESH_BINARY_INV);
- imshow("分割",result);
- }
- if(model==2)
- {
- threshold(srcimage,result,thresholds,255,THRESH_TRUNC);
- imshow("分割",result);
- }
- if(model==3)
- {
- threshold(srcimage,result,thresholds,255,THRESH_TOZERO);
- imshow("分割",result);
- }
- if(model==4)
- {
- threshold(srcimage,result,thresholds,255,THRESH_TOZERO_INV);
- imshow("分割",result);
- }
- }
- int main()
- {
- image=imread("2.2.tif");
- if(!image.data)
- {
- return 0;
- }
- cvtColor(image,srcimage,CV_BGR2GRAY);
- namedWindow("分割",WINDOW_AUTOSIZE);
- cv::createTrackbar("阈a值:","分割",&thresholds,255,track);
- cv::createTrackbar("模式:","分割",&model,4,track);
- track(thresholds,0);
- track(model,0);
- waitKey(0);
- return 0;
- }
实现结果:

2、阈值处理
- //阈值处理
- #include "opencv2/core/core.hpp"
- #include "opencv2/highgui/highgui.hpp"
- #include "opencv2/imgproc/imgproc.hpp"
-
- using namespace cv;
- using namespace std;
-
- int main()
- {
- printf("键盘按键ESC--退出程序");
- Mat g_srcImage = imread("1.tif",0);
- if(!g_srcImage.data)
- {
- printf("读取图片失败");
- }
- imshow("原始图",g_srcImage);
-
- //大津法阈值分割显示
- /*大津法,简称OTSU.它是按图像的灰度特性,将图像分成背景
- 和目标2部分。背景和目标之间的类间方差越大,说明构成图像
- 的2部分的差别越大,当部分目标错分为背景或部分背景错分为
- 目标都会导致2部分差别变小。*/
- Mat OtsuImage;
- threshold(g_srcImage,OtsuImage,0,255,THRESH_OTSU);//0不起作用,可为任意阈值
- imshow("OtsuImage",OtsuImage);
-
- //自适应分割并显示
- Mat AdaptImage;
- //THRESH_BINARY_INV:参数二值化取反
- adaptiveThreshold(g_srcImage,AdaptImage,255,0,THRESH_BINARY_INV,7,8);
- imshow("AdaptImage",AdaptImage);
-
- while(1)
- {
- int key;
- key = waitKey(20);
- if((char)key == 27)
- { break; }
- }
- }
效果图:

3、拉普拉斯检测
- //Laplacian检测
- #include "opencv2/core/core.hpp"
- #include "opencv2/highgui/highgui.hpp"
- #include "opencv2/imgproc/imgproc.hpp"
- using namespace cv;
- using namespace std;
-
- /*,在只关心边缘的位置而不考虑其周围的象素灰度差值时比较合适。
- Laplace 算子对孤立象素的响应要比对边缘或线的响应要更强烈,因此
- 只适用于无噪声图象。存在噪声情况下,使用 Laplacian 算子检测边
- 缘之前需要先进行低通滤波。*/
- int main()
- {
- Mat src,src_gray,dst,abs_dst;
- src = imread("1.jpg");
- imshow("原始图像",src);
-
- //高斯滤波
- GaussianBlur(src,src,Size(3,3),0,0,BORDER_DEFAULT);
- //转化为灰度图,输入只能为单通道
- cvtColor(src,src_gray,CV_BGR2GRAY);
-
- Laplacian(src_gray,dst,CV_16S,3,1,0,BORDER_DEFAULT);
- convertScaleAbs(dst,abs_dst);
- imshow("效果图Laplace变换",abs_dst);
- waitKey();
- return 0;
-
- }
效果图:

4、canny算法的边缘检测
源代码
- #include "opencv2/core/core.hpp"
- #include "opencv2/highgui/highgui.hpp"
- #include "opencv2/imgproc/imgproc.hpp"
- using namespace cv;
- using namespace std;
- /*如果某一像素位置的幅值超过高阈值,该像素被保留为边缘像素。如果某
- 一像素位置的幅值小于低阈值,该像素被排除。如果某一像素位置的幅值在
- 两个阈值之间,该像素仅仅在连接到一个高于高阈值的像素时被保留。 */
- int main()
- {
- Mat picture2=imread("1.jpg");
- Mat new_picture2;
- Mat picture2_1=picture2.clone();
- Mat gray_picture2 , edge , new_edge;
- imshow("【原始图】Canny边缘检测" , picture2);
- Canny(picture2_1 , new_picture2 ,150 , 100 ,3 );
- imshow("【效果图】Canny边缘检测", new_picture2 );
- Mat dstImage,grayImage;
- //dstImage与srcImage同大小类型
- dstImage.create(picture2_1.size() , picture2_1.type());
- cvtColor(picture2_1,gray_picture2,CV_BGR2GRAY);//转化为灰度图
- blur(gray_picture2 , edge , Size(3,3));//用3x3的内核降噪
- Canny(edge,edge,3,9,3);
- dstImage = Scalar::all(0);//将dst内所有元素设置为0
- //使用canny算子的边缘图edge作为掩码,将原图拷贝到dst中
- picture2_1.copyTo(dstImage,edge);
- imshow("效果图Canny边缘检测2",dstImage);
- waitKey();
- }
效果图:

5、图像的分水岭算法
源代码:
- #include "opencv2/core/core.hpp"
- #include "opencv2/highgui/highgui.hpp"
- #include "opencv2/imgproc/imgproc.hpp"
- #include <iostream>
-
- using namespace cv;
- using namespace std;
-
- #define WINDOW_NAME1 "显示/操作窗口"
- #define WINDOW_NAME2 "分水岭算法效果图"
-
- Mat g_maskImage,g_srcImage;
- Point prevPt(-1,-1);
-
- static void ShowHelpText();
- static void on_Mouse(int event,int x,int y,int flags,void*);
-
- //输出一些帮助信息
- static void ShowHelpText()
- {
- printf("当前使用的版本为:"CV_VERSION);
- printf("\n");
- printf("分水岭算法---点中图片进行鼠标或按键操作\n");
- printf("请先用鼠标在图片窗口中标记出大致的区域,\n然后再按键【1】或者【space】启动算法");
- printf("\n按键操作说明:\n"
- "键盘按键【1】或者【space】--运行的分水岭分割算法\n"
- "键盘按键【2】--回复原始图片\n"
- "键盘按键【ESC】--退出程序\n");
- }
-
- static void on_Mouse(int event,int x,int y,int flags,void*)
- {
- if(x<0||x>=g_srcImage.cols||y<0||y>=g_srcImage.rows)
- return;
-
-
- if(event == CV_EVENT_LBUTTONUP||!(flags & CV_EVENT_FLAG_LBUTTON))
- prevPt = Point(-1,-1);
-
- else if(event == CV_EVENT_LBUTTONDOWN)
- prevPt= Point(x,y);
-
- else if(event == CV_EVENT_MOUSEMOVE && (flags & CV_EVENT_FLAG_LBUTTON))
- {
- Point pt(x,y);
- if(prevPt.x<0)
- prevPt = pt;
- line(g_maskImage,prevPt,pt,Scalar::all(255),5,8,0);
- line(g_srcImage,prevPt,pt,Scalar::all(255),5,8,0);
- prevPt = pt;
- imshow(WINDOW_NAME1,g_srcImage);
- }
- }
-
- int main(int argc,char** argv)
- {
- system("color A5");
-
- ShowHelpText();
-
- g_srcImage = imread("1.jpg",1);
- imshow(WINDOW_NAME1,g_srcImage);
- Mat srcImage,grayImage;
- g_srcImage.copyTo(srcImage);
- cvtColor(g_srcImage,g_maskImage,CV_BGR2GRAY);
- cvtColor(g_maskImage,grayImage,CV_GRAY2BGR);//灰度图转BGR3通道,但每通道的值都是原先单通道的值,所以也是显示灰色的
- g_maskImage = Scalar::all(0);//黑
-
- setMouseCallback(WINDOW_NAME1,on_Mouse,0);
-
- while(1)
- {
- int c = waitKey(0);
- if((char)c == 27)
- break;
- if((char)c == '2')
- {
- g_maskImage = Scalar::all(0);//黑
- srcImage.copyTo(g_srcImage);
- imshow("image",g_srcImage);
- }
- if((char)c == '1'||(char)c == ' ')
- {
- int i,j,compCount = 0;
- vector<vector<Point>> contours;//定义轮廓
- vector<Vec4i> hierarchy;//定义轮廓的层次
-
- findContours(g_maskImage,contours,hierarchy,RETR_CCOMP,CHAIN_APPROX_SIMPLE);
- if(contours.empty())
- continue;
- Mat maskImage(g_maskImage.size(),CV_32S);
- maskImage = Scalar::all(0);
-
- for(int index = 0;index >= 0;index = hierarchy[index][0],compCount++)
- drawContours(maskImage,contours,index,Scalar::all(compCount+1),-1,8,hierarchy,INT_MAX);
- if(compCount == 0)
- continue;
- vector<Vec3b> colorTab;
- for(i=0;i<compCount;i++)
- {
- int b = theRNG().uniform(0,255);
- int g = theRNG().uniform(0,255);
- int r = theRNG().uniform(0,255);
- colorTab.push_back(Vec3b((uchar)b,(uchar)g,(uchar)r));
- }
- //计算处理时间并输出到窗口中
- double dTime = (double)getTickCount();
- watershed(srcImage,maskImage);
- dTime = (double)getTickCount()-dTime;
- printf("\t处理时间=%gms\n",dTime*1000./getTickFrequency());
- //双层循环,将分水岭图像遍历存入watershedImage中
- Mat watershedImage(maskImage.size(),CV_8UC3);
- for(i=0;i<maskImage.rows;i++)
- for(j=0;j<maskImage.cols;j++)
- {
- int index = maskImage.at<int>(i,j);
- if(index == -1)
- watershedImage.at<Vec3b>(i,j) = Vec3b(255,255,255);
- else if(index<=0||index>compCount)
- watershedImage.at<Vec3b>(i,j) = Vec3b(0,0,0);
- else
- watershedImage.at<Vec3b>(i,j) = colorTab[index-1];
- }
- //混合灰度图和分水岭效果图并显示最终的窗口
- watershedImage = watershedImage*0.5+grayImage*0.5;
- imshow(WINDOW_NAME2,watershedImage);
- }
- }
- waitKey();
- return 0;
- }
效果图:

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