Problem with deprecated conversion from cv::mat to IplImage

Question

I know there were already questions like this in the past but all the answers seem not to work anymore since some functions are deprecated so I hope you can help me.

That's what I try to do :

IplImage* image = 0;
Mat frame; 
image = cvCloneImage(&(IplImage)frame); 

Basically I get an error because of the last line :

E0312 no suitable user-defined conversion from "cv::Mat" to "IplImage" exists

By the way if instead there is a manual way to convert Mat to IplImage it's also great for me.

PS : I'm trying to use an old code so it doesn't bother me if Mat is the new standard in OpenCV and not advised using IplImage.

PS2 : If there is an old version of OpenCV that can do this without errors it's also OK.

Thank you!

Answer 1

I try to make hand-crafted conversion. In my enviroment it works well (OpenCV 2.4.9). Be carefull with pix_type variable value.

Mat frame_gray = imread("img.bmp");
int pix_type = IPL_DEPTH_8U;
IplImage* img = cvCreateImage(frame_gray.size(), pix_type , frame_gray.channels());
img->imageData = reinterpret_cast<char*>(frame_gray.data);
img->widthStep = frame_gray.step;

Answer 2

On modern versions of OpenCV (3.9 and later) you can use function cvIplImage:

Mat matImage;
IplImage iplImage = cvIplImage(matImage);