How to crop an image using C/C++ ?
I tried this example: http://stackoverflow.com/a/15748297,
#include <opencv2/opencv.hpp>
#include <highgui.h>
int main(int argc, char* argv[])
{
cv::Mat img = cv::imread(argv[1]);
if (img.empty())
{
std::cout << "!!! imread() failed to open target image" << std::endl;
return -1;
}
/* Set Region of Interest */
int offset_x = 129;
int offset_y = 129;
cv::Rect roi;
roi.x = offset_x;
roi.y = offset_y;
roi.width = img.size().width - (offset_x*2);
roi.height = img.size().height - (offset_y*2);
/* Crop the original image to the defined ROI */
cv::Mat crop = img(roi);
cv::imshow("crop", crop);
cv::waitKey(0);
cv::imwrite("noises_cropped.png", crop);
return 0;
}
but when I launch it some windows appears and it can't rewrite existing image, it can write to another one, but I don't need it, I want it to do silently - without windows, and better to rewrite existing image. C++ is preferable.