Hi, I would be grateful if someone could point me to methods of calculations applicable here.

The camera is always oriented in a way that lower border of HFOV (horizontal field of view) is aligned with the bottom side of the object. The dimension of the object for a reference camera tilt angle is given as well as the contour area of this object on the image plane. The reference tilt angle is defined by camera height and distance to the object which are known. Parameters of the camera (fields of view, focal length) are the so known.

Is it possible to calculate new changed contour area on image plane when camera tilt angle is changed (due to changing object distance or/and camera height)?

I have found such method as camera transform using pinhole camera model to represent object in 3d space on 2d plane, but seems that it is not what I am looking for.

There is a library called OpenCV. It has functionality for finding contours, and giving the contours' area and centre.

4 minutes ago, taby said:

There is a library called OpenCV. It has functionality for finding contours, and giving the contours' area and centre.

Yes, I am aware of this functionality, but here the challenge is to calculate (predict) contour area of the object a priori. But yes, one of variants is to emulate possible scenarios and get a curve experimentally using for example OpenCV. Anyway thanks!

I am sorry that I didn't understand your goal.