#include<opencv2/opencv.hpp> using namespace cv; #define WINDOW_NAME "[程序窗口]" Rect g_rectangle; bool g_bDrawingBox = false;//是否进行绘制 RNG g_rng(12345);//RNG( )函数的作用为初始化随机数状态的生成器; void DrawRectangle(cv::Mat &img, cv::Rect box) { /* 构造函数 Rect(x,y,width,height),x, y 为左上角坐标, width, height 则为长和宽。 利用对角线两点来画矩形: void rectangle(Mat& img, Point pt1,Point pt2,const Scalar& color, int thickness=1, int lineType=8, int shift=0) 传入矩形参数来画矩形: void rectangle(Mat& img, Rect rec, const Scalar& color, int thickness=1, int lineType=8, int shift=0 ) */ rectangle(img, box.tl(), box.br(),Scalar(g_rng.uniform(0, 255), g_rng.uniform(0, 255), g_rng.uniform(0, 255)));//随机颜色 } void on_MouseHandle(int event, int x, int y, int flags, void *param) { Mat &image = *(cv::Mat*)param; switch (event) { //鼠标移动消息 case EVENT_MOUSEMOVE: { //如果是否进行绘制的标识符为真,则记录下长宽到RECT变量中 if (g_bDrawingBox) { g_rectangle.width = x - g_rectangle.x; g_rectangle.height = y - g_rectangle.y; } } break; //左键按下 case EVENT_LBUTTONDOWN: { g_bDrawingBox = true; g_rectangle = Rect(x, y, 0, 0);//记录起始点 } break; //左键抬起 case EVENT_LBUTTONUP: { g_bDrawingBox = false;//抬起就不画了 //对于宽或高小于0 if (g_rectangle.width < 0) { g_rectangle.x += g_rectangle.width; g_rectangle.width *= -1; } if (g_rectangle.height < 0) { g_rectangle.y += g_rectangle.height; g_rectangle.height *= -1; } //开始绘制 DrawRectangle(image, g_rectangle); } break; default: break; } } int main() { g_rectangle = Rect(-1, -1, 0, 0);//起始位置 Mat srcImage(600, 800, CV_8UC3), tempImage; /* 使用Mat( )构造函数 Mat M(2,2,CV_8UC3,Scalar(0,0,255)); 参数: 1)行数和列数; 2)存储元素的数据类型以及每个矩阵点的通道数;CV_8UC3表示使用8位的unsigned char型,每个元素由三个元素组成三通道。 3)Scalar是个short型的向量,能够用指定的定制化的值来初始化矩阵,还可以用于表示颜色。 */ srcImage.copyTo(tempImage);//将srcImage拷贝到tempImage g_rectangle = Rect(-1, -1, 0, 0); srcImage = Scalar::all(0); //设置鼠标操作回调函数 namedWindow(WINDOW_NAME); setMouseCallback(WINDOW_NAME, on_MouseHandle, (void*)&srcImage); while (1) { srcImage.copyTo(tempImage);//复制原图到临时变量 if (g_bDrawingBox)//当标识符为真,则进行绘制 DrawRectangle(tempImage, g_rectangle); imshow(WINDOW_NAME,tempImage); if (waitKey(10) == 27)//按esc退出 break; } return 0; }
效果图: