在OpenCV中鼠標移動區域局部放大

這個程序類似於淘寶購物時，在商品圖像上移動鼠標，會出現一個放大鼠標周圍矩形區域內的局部圖像的窗口。話不多說，直接貼代碼。

1. #include <cv.h>  
2. #include <highgui.h>  
3. #include <stdio.h>  
4. #pragma comment( lib, "cv.lib" )  
5. #pragma comment( lib, "cxcore.lib" )  
6. #pragma comment( lib, "highgui.lib" )   
7. IplImage* org = 0;  
8. IplImage* img = 0;   
9. IplImage* dst = 0;   
10. int foo=60;  
11. void on_mouse( int event, int x, int y, int flags, void* ustc)  
12. {  
13.     if( event == CV_EVENT_MOUSEMOVE && !(flags & CV_EVENT_FLAG_LBUTTON))  
14.     {  
15.         cvCopy(org,img);  
16.         CvPoint p0;  
17.         CvPoint p1;  
18.         if(x<foo)  
19.         {  
20.             if(y<foo)  
21.             {  
22.                 p0=cvPoint(0,0);  
23.                 p1=cvPoint(2*foo,2*foo);  
24.             }  
25.             else if(y>img->height-foo)  
26.             {   
27.                 p0=cvPoint(0,img->height-2*foo);  
28.                 p1=cvPoint(2*foo,img->height);  
29.             }  
30.             else  
31.             {  
32.                 p0=cvPoint(0,y-foo);  
33.                 p1=cvPoint(2*foo,y+foo);  
34.             }  
35.         }  
36.         else if(x>img->width-foo)  
37.         {  
38.             if(y<foo)  
39.             {  
40.                 p0=cvPoint(img->width-2*foo,0);  
41.                 p1=cvPoint(img->width,2*foo);  
42.             }  
43.             else if(y>img->height-foo)  
44.             {   
45.                 p0=cvPoint(img->width-2*foo,img->height-2*foo);  
46.                 p1=cvPoint(img->width,img->height);  
47.             }  
48.             else  
49.             {  
50.                 p0=cvPoint(img->width-2*foo,y-foo);  
51.                 p1=cvPoint(img->width,y+foo);  
52.             }  
53.         }  
54.         else  
55.         {  
56.             if(y<foo)  
57.             {  
58.                 p0=cvPoint(x-foo,0);  
59.                 p1=cvPoint(x+foo,2*foo);  
60.             }  
61.             else if(y>img->height-foo)  
62.             {   
63.                 p0=cvPoint(x-foo,img->height-2*foo);  
64.                 p1=cvPoint(x+foo,img->height);  
65.             }  
66.             else  
67.             {  
68.                 p0=cvPoint(x-foo,y-foo);  
69.                 p1=cvPoint(x+foo,y+foo);  
70.             }  
71.         }  
72.         cvRectangle(img,p0,p1,CV_RGB(0,255,0));  
73.         cvSetImageROI(org,cvRect(p0.x,p0.y,p1.x-p0.x,p1.y-p0.y));  
74.         cvResize(org,dst);  
75.         cvResetImageROI(org);  
76.         cvShowImage( "img", img );  
77.         cvShowImage("dst",dst);  
78.     }  
79. }  
80. int main()  
81. {  
82.     org=cvLoadImage("lena.jpg",1);  
83.     img=cvCloneImage(org);  
84.     dst=cvCreateImage(cvSize(foo*4,foo*4),org->depth,org->nChannels);  
85.     cvNamedWindow("img",1);  
86.     cvSetMouseCallback( "img", on_mouse, 0 );  
87.     cvShowImage("img",img);  
88.     cvNamedWindow("dst",1);  
89.     cvWaitKey(0);   
90.     cvDestroyAllWindows();  
91.     cvReleaseImage(&org);  
92.     cvReleaseImage(&img);  
93.     cvReleaseImage(&dst);  
94.     return 0;  
95. }  

效果圖如下