Creating our own crop rect in camera overlay

Before placing my question, I want to state my basic requirement which is to change the frame for crop rect in UIImagePickerController for a camera.

I just realized that it is not possible to change frame for crop rect. That leaves me with only one option i.e to create my own camera overlay wherein I can set frame for crop rect. I searched a lot but found nothing. I asked previously but didn't get anything. I don't even know is it possible and if yes then how to create it and move the crop box, scale it in accordance to default UIImagePickerController crop rect.

Can someone help me here?

Thanks,

Nitish

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