Title: How to Crop Predefined Regions from an Image using C# and OpenCV?

Body:
I am working on a project in C# and OpenCV where I need to crop a specific region from an image and save it as a PNG file. The images I am working with always have an elephant in the same size and position, and I need to crop this elephant out of the image.

Here is an example image for reference (imagine there’s an image attached showing an elephant).

I am relatively new to image processing with OpenCV and C#, so I am not sure where to start. Could someone provide guidance or code examples on how to achieve this?

Key points:

1. The region to be cropped is predefined and consistent across all images.
2. I need to crop this region and save the cropped image as a PNG file.
3. I am using C# with WPF and OpenCV.

If anyone has experience with similar tasks or can provide a sample code snippet, it would be greatly appreciated!

Thank you!