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### how can I reproject points once I have the homography matrix?

Hi all! I have calculated a homography matrix using cvFindHomography() and now I would like to use this matrix to do some point reprojection.

originally, i thought I could simply do

p' = H * p, where H my is my obtained (3x3) homography matrix, p is my original point a Vec3f point (with z=0) p' is my reprojected point (again Vec3f).

apparently the compiler whines though that the "*" operator has not been defined for such multiplication.

What could be wrong? I am using the operator "*" in some wrong way?