Inverse perspective transformation is an image processing technology used to transform a perspective transformed image into a normal perspective image.
He will assume the ground is flat.
cv::warpPerspective is a function used to implement IPM in opencv. It is generally used to reverse perspective transformation of an image or a specific area in an image.
First we need to get the inverse perspective transformation matrix, which can be obtained from the internal and external parameters of the camera, or calculated from the four corresponding point sets before and after the view transformation.
Then define the mapping area, defining a rectangular area on the top view that corresponds to the area of interest. The location and size of this area can be adjusted according to actual needs.
Multiply the front view with the inverse perspective transformation matrix to get the top view result.