Rectangle trapezoid

I collect frames from the camera and try to do some image processing and OCR. When the camera is perpendicular to the target, I have no problem with cropping and image processing. But when I try to capture a frame with an angle, the target will most likely turn into a trapezoid, not a rectangle.

I use OpenCV for all image processing products. I was wondering what can I do to get the area I want when its trapezoid?

For example, can I somehow convert a trapezoidal image into a rectangle using OpenCV?

thank