自学建百度首页网站,python做网站多么,wordpress微交易,外贸营销是做什么的OpenCV C案例实战三十一《动态时钟》 前言一、绘制表盘二、绘制刻线三、获取系统时间四、结果展示五、源码总结 前言
本案例将使用OpenCV C实现动态时钟效果。原理也很简单#xff0c;主要分为绘制表盘、以及获取系统时间两步。
一、绘制表盘
首先为了效果显示美观一点案例实战三十一《动态时钟》 前言一、绘制表盘二、绘制刻线三、获取系统时间四、结果展示五、源码总结 前言
本案例将使用OpenCV C实现动态时钟效果。原理也很简单主要分为绘制表盘、以及获取系统时间两步。
一、绘制表盘
首先为了效果显示美观一点选取一张背景图。 接着需要绘制一个圆形表盘直接上代码、效果演示。注释都在源码上有标注。 Point center(background.cols / 2, background.rows / 2);//圆心int radius min(background.cols / 2, background.rows / 2) - 20; //时钟半径Mat mask Mat::zeros(background.size(), CV_8UC3);circle(mask, center, radius, Scalar::all(255), -1);//掩模Mat canvas Mat(background.size(), CV_8UC3, Scalar(175, 165, 0));//创建画布background.copyTo(canvas, mask);//将背景拷贝到画布中形成表盘背景circle(canvas, center, radius, Scalar::all(0), 3);//表盘二、绘制刻线
接下来需要在表盘上绘制时针、分针刻线。其中原理就是计算点的旋转坐标。可以参考一下我的这篇博文OpenCV C案例实战二十七《角度测量》 int margin 5;//若margin为0则点在表盘上//画分针刻线int minute_len 10; //刻线长度for (int i 0; i 60; i){//圆上坐标点计算公式对于分针刻线360/606即每隔6°一刻线int x1 center.x (radius - margin) * cos(i*6.0*CV_PI / 180.0);int y1 center.y (radius - margin) * sin(i*6.0*CV_PI / 180.0);int x2 center.x (radius - minute_len) * cos(i*6.0*CV_PI / 180.0);int y2 center.y (radius - minute_len) * sin(i*6.0*CV_PI / 180.0);line(canvas, Point(x1, y1), Point(x2, y2), Scalar::all(0), 2, LINE_AA);}//画时针刻线int hour_len 20;for (int i 0; i 12; i){//对于时针刻线每隔360/1230即每隔30°一刻线int x1 center.x (radius - margin) * cos(i*30.0*CV_PI / 180.0);int y1 center.y (radius - margin) * sin(i*30.0*CV_PI / 180.0);int x2 center.x (radius - hour_len)*cos(i*30.0*CV_PI / 180.0);int y2 center.y (radius - hour_len)*sin(i*30.0*CV_PI / 180.0);line(canvas, Point(x1, y1), Point(x2, y2), Scalar::all(0), 3, LINE_AA);//在表盘上显示3、6、9、12时坐标位置自行根据图像大小设定if (i 0){putText(canvas, to_string(i 3), Point(x2 - 30, y2 10), FONT_HERSHEY_SIMPLEX, 1, Scalar::all(0), 3);}else if (i 3){putText(canvas, to_string(i 3), Point(x2 - 10, y2 - 10), FONT_HERSHEY_SIMPLEX, 1, Scalar::all(0), 3);}else if (i 6){putText(canvas, to_string(i 3), Point(x2 10, y2 10), FONT_HERSHEY_SIMPLEX, 1, Scalar::all(0), 3);}else if (i 9){putText(canvas, to_string(i 3), Point(x2 - 20, y2 30), FONT_HERSHEY_SIMPLEX, 1, Scalar::all(0), 3);}}效果如上图所示至此前期的预处理工作已经完成了。接下来需要获取系统时间然后绘制到表盘上。
三、获取系统时间
当我们获取到相应的系统时间后有一点需要注意的是opencv是以3点钟方向为起点即0°方向且为顺时针旋转故秒针、分针、时针在0~3点钟区间需要换算。具体换算请看源码注释。 //使用while循环不断更新时间while (true){ char key waitKey(1000);if (key 27)break;Mat clockImg canvas.clone();//将表盘复制一份用于不断更新时钟刻线//获取系统时间SYSTEMTIME Time;GetLocalTime(Time);int second Time.wSecond; //秒int minute Time.wMinute; //分int hour Time.wHour; //时int day Time.wDay; //日int month Time.wMonth; //月int year Time.wYear; //年printf(%4d/%02d/%02d %02d:%02d:%02d\n, year, month, day, hour, minute, second);//由于opencv是以3点钟方向为起点且为顺时针旋转故秒针、分针、时针在0~3点钟区间需要换算//秒针int sec_angle 0;if (second 15){//当秒针处于0~15秒时对应角度应处于270~360°每隔6°走一刻线sec_angle second * 6 270;}else{sec_angle (second - 15) * 6;}int sec_x center.x (radius - margin * 12) *cos(sec_angle*CV_PI / 180);int sec_y center.y (radius - margin * 12) *sin(sec_angle*CV_PI / 180);line(clockImg, center, Point(sec_x, sec_y), Scalar(0, 255, 0), 2, LINE_AA);//分针int min_angle 0;if (minute 15){//当分针处于0~15分时对应角度应处于270~360°每隔6°走一刻线min_angle minute * 6 270;}else{min_angle (minute - 15) * 6;}int min_x center.x (radius - margin*18)*cos(min_angle*CV_PI / 180);int min_y center.y (radius - margin*18)*sin(min_angle*CV_PI / 180);line(clockImg, center, Point(min_x, min_y), Scalar(0, 255, 255), 4, LINE_AA);//时针int hour_angle 0;if (hour 3){//当时针处于0~3时对应角度应处于270~360°每隔30°走一刻线hour_angle hour * 30 270;}else{hour_angle (hour - 3) * 30;}int hour_x center.x (radius - margin * 24)*cos(hour_angle*CV_PI / 180);int hour_y center.y (radius - margin * 24)*sin(hour_angle*CV_PI / 180);line(clockImg, center, Point(hour_x, hour_y), Scalar(255, 255, 0), 6, LINE_AA);circle(clockImg, center, 5, Scalar::all(0), -1);//将时间显示在表盘上char text1[100], text2[100];sprintf_s(text1, %04d%s%02d%s%02d, year, /, month, /, day);sprintf_s(text2, %02d%s%02d%s%02d, hour, :, minute, :, second);putText(clockImg, text1, Point(center.x-100, center.y200), FONT_HERSHEY_SIMPLEX, 1, Scalar(21, 23, 161), 3);putText(clockImg, text2, Point(center.x-70, center.y250), FONT_HERSHEY_SIMPLEX, 1, Scalar(21, 23, 161), 2);imshow(dynamic clock, clockImg);imwrite(dynamic clock.jpg, clockImg);}四、结果展示 五、源码
#includeiostream
#includeopencv2/opencv.hpp
#includeWindows.h
using namespace std;
using namespace cv;int main()
{Mat background imread(background.jpg);if (background.empty()){cout can not read the image... endl;system(pause);return -1;}Point center(background.cols / 2, background.rows / 2);//圆心int radius min(background.cols / 2, background.rows / 2) - 20; //时钟半径Mat mask Mat::zeros(background.size(), CV_8UC3);circle(mask, center, radius, Scalar::all(255), -1);//掩模Mat canvas Mat(background.size(), CV_8UC3, Scalar(175, 165, 0));//创建画布background.copyTo(canvas, mask);//将背景拷贝到画布中形成表盘背景circle(canvas, center, radius, Scalar::all(0), 3);//表盘int margin 5;//若margin为0则点在表盘上//画分针刻线int minute_len 10; //刻线长度for (int i 0; i 60; i){//圆上坐标点计算公式对于分针刻线360/606即每隔6°一刻线int x1 center.x (radius - margin) * cos(i*6.0*CV_PI / 180.0);int y1 center.y (radius - margin) * sin(i*6.0*CV_PI / 180.0);int x2 center.x (radius - minute_len) * cos(i*6.0*CV_PI / 180.0);int y2 center.y (radius - minute_len) * sin(i*6.0*CV_PI / 180.0);line(canvas, Point(x1, y1), Point(x2, y2), Scalar::all(0), 2, LINE_AA);}//画时针刻线int hour_len 20;for (int i 0; i 12; i){//对于时针刻线每隔360/1230即每隔30°一刻线int x1 center.x (radius - margin) * cos(i*30.0*CV_PI / 180.0);int y1 center.y (radius - margin) * sin(i*30.0*CV_PI / 180.0);int x2 center.x (radius - hour_len)*cos(i*30.0*CV_PI / 180.0);int y2 center.y (radius - hour_len)*sin(i*30.0*CV_PI / 180.0);line(canvas, Point(x1, y1), Point(x2, y2), Scalar::all(0), 3, LINE_AA);//在表盘上显示3、6、9、12时坐标位置自行根据图像大小设定if (i 0){putText(canvas, to_string(i 3), Point(x2 - 30, y2 10), FONT_HERSHEY_SIMPLEX, 1, Scalar::all(0), 3);}else if (i 3){putText(canvas, to_string(i 3), Point(x2 - 10, y2 - 10), FONT_HERSHEY_SIMPLEX, 1, Scalar::all(0), 3);}else if (i 6){putText(canvas, to_string(i 3), Point(x2 10, y2 10), FONT_HERSHEY_SIMPLEX, 1, Scalar::all(0), 3);}else if (i 9){putText(canvas, to_string(i 3), Point(x2 - 20, y2 30), FONT_HERSHEY_SIMPLEX, 1, Scalar::all(0), 3);}}//使用while循环不断更新时间while (true){ char key waitKey(1000);if (key 27)break;Mat clockImg canvas.clone();//将表盘复制一份用于不断更新时钟刻线//获取系统时间SYSTEMTIME Time;GetLocalTime(Time);int second Time.wSecond; //秒int minute Time.wMinute; //分int hour Time.wHour; //时int day Time.wDay; //日int month Time.wMonth; //月int year Time.wYear; //年printf(%4d/%02d/%02d %02d:%02d:%02d\n, year, month, day, hour, minute, second);//由于opencv是以3点钟方向为起点且为顺时针旋转故秒针、分针、时针在0~3点钟区间需要换算//秒针int sec_angle 0;if (second 15){//当秒针处于0~15秒时对应角度应处于270~360°每隔6°走一刻线sec_angle second * 6 270;}else{sec_angle (second - 15) * 6;}int sec_x center.x (radius - margin * 12) *cos(sec_angle*CV_PI / 180);int sec_y center.y (radius - margin * 12) *sin(sec_angle*CV_PI / 180);line(clockImg, center, Point(sec_x, sec_y), Scalar(0, 255, 0), 2, LINE_AA);//分针int min_angle 0;if (minute 15){//当分针处于0~15分时对应角度应处于270~360°每隔6°走一刻线min_angle minute * 6 270;}else{min_angle (minute - 15) * 6;}int min_x center.x (radius - margin*18)*cos(min_angle*CV_PI / 180);int min_y center.y (radius - margin*18)*sin(min_angle*CV_PI / 180);line(clockImg, center, Point(min_x, min_y), Scalar(0, 255, 255), 4, LINE_AA);//时针int hour_angle 0;if (hour 3){//当时针处于0~3时对应角度应处于270~360°每隔30°走一刻线hour_angle hour * 30 270;}else{hour_angle (hour - 3) * 30;}int hour_x center.x (radius - margin * 24)*cos(hour_angle*CV_PI / 180);int hour_y center.y (radius - margin * 24)*sin(hour_angle*CV_PI / 180);line(clockImg, center, Point(hour_x, hour_y), Scalar(255, 255, 0), 6, LINE_AA);circle(clockImg, center, 5, Scalar::all(0), -1);//将时间显示在表盘上char text1[100], text2[100];sprintf_s(text1, %04d%s%02d%s%02d, year, /, month, /, day);sprintf_s(text2, %02d%s%02d%s%02d, hour, :, minute, :, second);putText(clockImg, text1, Point(center.x-100, center.y200), FONT_HERSHEY_SIMPLEX, 1, Scalar(21, 23, 161), 3);putText(clockImg, text2, Point(center.x-70, center.y250), FONT_HERSHEY_SIMPLEX, 1, Scalar(21, 23, 161), 2);imshow(dynamic clock, clockImg);imwrite(dynamic clock.jpg, clockImg);}destroyAllWindows();system(pause);return 0;
}总结
本文使用OpenCV C 进行动态时钟绘制主要操作有以下几点。 1、图像预处理绘制表盘 2、绘制表盘刻线 3、获取系统时间注意角度与时间之间的转换
