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/*
* starter_video.cpp
*
* Created on: Nov 23, 2010
* Author: Ethan Rublee
*
* A starter sample for using opencv, get a video stream and display the images
* easy as CV_PI right?
*/
#include "opencv2/highgui/highgui.hpp"
#include <iostream>
#include <vector>
#include <stdio.h>
using namespace cv;
using namespace std;
//hide the local functions in an anon namespace
namespace {
void help(char** av) {
cout << "\nThis program justs gets you started reading images from video\n"
"Usage:\n./" << av[0] << " <video device number>\n"
<< "q,Q,esc -- quit\n"
<< "space -- save frame\n\n"
<< "\tThis is a starter sample, to get you up and going in a copy pasta fashion\n"
<< "\tThe program captures frames from a camera connected to your computer.\n"
<< "\tTo find the video device number, try ls /dev/video* \n"
<< "\tYou may also pass a video file, like my_vide.avi instead of a device number"
<< endl;
}
int process(VideoCapture& capture) {
int n = 0;
char filename[200];
string window_name = "video | q or esc to quit";
cout << "press space to save a picture. q or esc to quit" << endl;
namedWindow(window_name, CV_WINDOW_KEEPRATIO); //resizable window;
Mat frame;
for (;;) {
capture >> frame;
if (frame.empty())
break;
imshow(window_name, frame);
char key = (char)waitKey(5); //delay N millis, usually long enough to display and capture input
switch (key) {
case 'q':
case 'Q':
case 27: //escape key
return 0;
case ' ': //Save an image
sprintf(filename,"filename%.3d.jpg",n++);
imwrite(filename,frame);
cout << "Saved " << filename << endl;
break;
default:
break;
}
}
return 0;
}
}
int main(int ac, char** av) {
if (ac != 2) {
help(av);
return 1;
}
std::string arg = av[1];
VideoCapture capture(arg); //try to open string, this will attempt to open it as a video file
if (!capture.isOpened()) //if this fails, try to open as a video camera, through the use of an integer param
capture.open(atoi(arg.c_str()));
if (!capture.isOpened()) {
cerr << "Failed to open a video device or video file!\n" << endl;
help(av);
return 1;
}
return process(capture);
}
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