Finding translation and scale on two sets of points to get least square error in their distance?

Question

I have two sets of 3D points (original and reconstructed) and correspondence information about pairs - which point from one set represents the second one. I need to find 3D

Answer 1

For 3D points the problem is known as the Absolute Orientation problem. A c++ implementation is available from Eigen http://eigen.tuxfamily.org/dox/group__Geometry__Module.html#gab3f5a82a24490b936f8694cf8fef8e60 and paper http://web.stanford.edu/class/cs273/refs/umeyama.pdf

you can use it via opencv by converting the matrices to eigen with cv::cv2eigen() calls.