OpenCV C++常用功能介绍

显示图片

1IplImage* img = cvLoadImage("～/temp.jpeg", 1);
2//create a window to display the image
3cvNamedWindow("picture", 1);
4//show the image in the window
5cvShowImage("picture", img);
6//wait for the user to hit a key
7cvWaitKey(0);
8//delete the image and window
9cvReleaseImage(&img);
10cvDestroyWindow("picture");

打开摄像头

1cvNamedWindow("CameraFrame", CV_WINDOW_AUTOSIZE);
2cv::VideoCapture cap(0);
3
4if (!cap.open(0)) {
5    return -1;
6}
7
8bool stop = false;
9cv::Mat frame;
10
11while(!stop) {
12    cap >> frame;
13    if (!frame.data) {
14        stop = true;
15        continue;
16    }
17    
18    imshow("CameraFrame", frame);
19    cvWaitKey(30);
20}

时间/日期

1struct timeval tv;
2struct timezone tz;
3
4// current time since 1900
5gettimeofday(&tv, &tz);
6
7// second
8printf("tv_sec:%ld\n",tv.tv_sec);
9// usecond
10printf("tv_usec:%ld\n",tv.tv_usec);
11
12printf("tz_minuteswest:%d\n",tz.tz_minuteswest);
13printf("tz_dsttime:%d\n",tz.tz_dsttime);
14
15struct tm *p;
16p = localtime(&tv.tv_sec);
17
18// data && time
19printf("time_now:%d/%d/%d %dh-%dm-%ds %ld\n",
20       1900+p->tm_year,
21       1+p->tm_mon,
22       p->tm_mday,
23       p->tm_hour,
24       p->tm_min,
25       p->tm_sec,
26       tv.tv_usec);

时间差/微妙级别

1static int getCurrentMicroSecond() {
2    struct timeval current;
3    double timer;
4    
5    gettimeofday(&current, NULL);
6    timer = 1000000 * current.tv_sec + current.tv_usec;
7    
8    return timer;
9}