例4-1......例4-2 鼠标在窗口中画矩形

//例4-1 用鼠标在窗口中画矩形#include "stdafx.h"#include <cv.h>#include <highgui.h>#include <stdlib.h>void my_mouse_callback(int event,int x,int y,int flag,void* param);CvRect box;bool drawing_box=false;void draw_box(IplImage* img,CvRect rect){cvRectangle(img,cvPoint(box.x,box.y),cvPoint(box.x+box.width,box.y+box.height),cvScalar(0xff,0x00,0x00));}int main(int argc, CHAR** argv){box=cvRect(-1,-1,0,0);IplImage* imge=cvCreateImage(cvSize(1200,700),IPL_DEPTH_8U,3);cvZero(imge);IplImage* temp=cvCloneImage(imge);cvNamedWindow("box example");cvSetMouseCallback("box example",my_mouse_callback,(void*)imge);while (1){cvCopyImage(imge,temp);if (drawing_box){draw_box(temp,box);}cvShowImage("box example",temp);if (cvWaitKey(15)==27){break;}}cvReleaseImage(&imge);cvReleaseImage(&temp);cvDestroyWindow("box example");//char jieshu;//scanf(&jieshu);return 0;}void my_mouse_callback(int event,int x,int y,int flag,void* param){IplImage* image=(IplImage*)param;switch (event){case CV_EVENT_MOUSEMOVE:{if (drawing_box){box.width=x-box.x;box.height=y-box.y;}}break;case CV_EVENT_LBUTTONDOWN:{drawing_box=true;box=cvRect(x,y,0,0);}break;case CV_EVENT_LBUTTONUP:{drawing_box=false;if (box.width<0){box.x+=box.width;box.width*=-1;}if (box.height<0){box.y+=box.height;box.height*=-1;}draw_box(image,box);}break;}}//例4-2 使用滑动条实现开关#include "stdafx.h"#include <cv.h>#include <highgui.h>int g_switch_value=0;void switch_callback(int position){if (position==0){switch_off_function();} else{switch_on_function();}}int _tmain(int argc, _TCHAR* argv[]){cvNamedWindow("Demo Window",1);cvCreateTrackbar("switch","Demo Window",&g_switch_value,1,switch_callback());while(1){if (cvWaitKey(15)==27){break;}}return 0;}

 

笔记：

• 分析一下