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Inverse Perspective Mapping

asked 2012-09-14 12:14:19 -0500

njaa gravatar image

updated 2012-11-25 05:23:01 -0500

sammy gravatar image


I would like to generate the birds eye view of an input image (given as Mat) with OpenCV. The intrinsic and extrinsic parameters of the camera are known.

Among other things I need to know the Viewpoint of the camera (l,h,d) and the viewing direction:


So my question is how can I determine these parameters with the help of the known intrinsic and extrinsic parameters? Or have I to measure them otherwise?

Thank you.

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answered 2012-09-17 07:51:09 -0500

Nghia gravatar image

I've done something similar a while ago. The gist of the solution is to project 4 imaginary lines from the corners of the camera. They will hit the ground and form a trapezoid shape when looked from above. You then take your 2D image and apply a homography that transforms the rectangle image to the trapezoid shape (with some appropriate scaling).

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Asked: 2012-09-14 12:14:19 -0500

Seen: 3,209 times

Last updated: Nov 25 '12