Is there a quicker way to get a snapshot? At the moment it is taking about 3 seconds. This will be running in the background so I don't need to see it. imwrite seems to do all the steps(even when I have closed it). Is there a different function that will do just the write?????

Thanks.

Hi There.

This may seem like an odd question but I cannot determine where the header files are located on my pc. There are gazillions of files in different folders but am not sure which one.

In my visual studio project (which works fine) the include directory is: C:\opencv 310\build\include. If lets say we view the highgui.hpp file from that folder the only code in it is:

ifdef __OPENCV_BUILD

error this is a compatibility header which should not be used inside the OpenCV library

endif

include "opencv2/highgui.hpp"

There is no reference to any source code here. According to this page (http://opencv-srf.blogspot.co.uk/2013...)

imread() is a function declared in "opencv2/highgui/highgui.hpp" header file.

Where can I view the actual source code for these functions and why is the header file from above not contain anything?

Mark.

Hi Folks.

I am trying to take a snapshot from a usb camera from the command line. I have it kind of working. I want to have 3 different commands: open, snapshot and close. I want to open the camera initially and then take snapshots as I please. However the frame grab seems to close the camera down and so it has to be opened again. Is it possible to use one command to open the camera and then another to grab the frame and another to close the camera and is it possible to grab a frame and leave the camera open? My code is below,

Thanks,

Mark.

include <opencv2 opencv.hpp="">

include <iostream>

using namespace cv; using namespace std;

std::string open_cmd("open"); std::string close_cmd("close"); std::string snapshot_cmd("snap");

int main(int argc, char argv[], char*) { //Open the first webcam plugged in the computer

cv::VideoCapture camera(2);
if (!camera.isOpened())
{
    std::cerr << "ERROR: Could not open camera" << std::endl;
    //return 1;
}


int count;

printf("This program was called with \"%s\".\n", argv[0]);

if (argc > 1)
{
    for (count = 1; count < argc; count++)
    {
        printf("argv[%d] = %s\n", count, argv[count]);
    }
}
else
{
    printf("The command had no other arguments.\n");
}

// return 0;

//Create a window to display the images from the webcam
cv::namedWindow("Webcam", CV_WINDOW_AUTOSIZE);

vector<int> compression_params;
compression_params.push_back(CV_IMWRITE_PNG_COMPRESSION);
compression_params.push_back(9);


//Pick up a new frame and display it until you press a key
while (1)
{
    //This will contain the image from the webcam
    cv::Mat frame;

    //Capture the next frame from the webcam
    camera >> frame;

    //Show the image on the window
    cv::imshow("Webcam", frame);

    std::string input_cmd(argv[1]);

    if (open_cmd.compare(input_cmd) == 0) {
        cv::VideoCapture camera(2);
        cv::imshow("Webcam", frame);
        //return 0;
    }
    else if (snapshot_cmd.compare(input_cmd) == 0) {
        camera >> frame;
        imwrite("MyImage.png", frame, compression_params);
        return 0;
    }
    else if (close_cmd.compare(input_cmd) == 0) {
        camera.release();
        //return 0;
    }


}

//Success. The program accomplished its mission and now it can go
// to the heaven of programs.
return 0;

}