Resize an image type “Mat” opencv C++

Question

I want to resize my image the code below works when the image is an IplImage but when i change it into Mat i get these errors: -Cannot convert \'cv::Mat::depth\' from type \

Answer 1

You can also use the code given below:

 Mat3b groupres;
 cvtColor(img, groupres, COLOR_GRAY2BGR);
 imshow("Grouped Result", groupres);
 Size size1(400, 450);
 resize(groupres, groupres, size1);
 waitKey();

the waitKey(); helps the image to stay and wait for a response.