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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
* Use http://datamatrix.kaywa.com/ to generate datamatrix images using strings of length 3 or less.
* easy as CV_PI right?
*/
#include "opencv2/highgui/highgui.hpp"
#include <opencv2/objdetect/objdetect.hpp>
#include <opencv2/imgproc/imgproc.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"
<< "\n"
<< "DATA:\n"
<< "Generate a datamatrix from from http://datamatrix.kaywa.com/ \n"
<< " NOTE: This only handles strings of len 3 or less\n"
<< " Resize the screen to be large enough for your camera to see, and it should find an read it.\n\n"
<< 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, WINDOW_KEEPRATIO); //resizable window;
Mat frame;
for (;;)
{
capture >> frame;
if (frame.empty())
break;
cv::Mat gray;
cv::cvtColor(frame,gray,COLOR_RGB2GRAY);
vector<String> codes;
Mat corners;
findDataMatrix(gray, codes, corners);
drawDataMatrixCodes(frame, codes, corners);
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);
}