homest Publisher's description
from Manolis Lourakis
A C/C++ Library for Robust, Non-linear Homography Estimation
homest is a C/C++ library for homography estimation that is distributed under the GNU General Public License (GPL). A homography (sometimes also called a collineation) is a general plane to plane projective transformation whose estimation from matched image features is often necessary in several vision tasks. A homography has eight degrees of freedom and is represented by a non-singular homogeneous 3x3 matrix.
homest implements a technique for non-linear, robust homography estimation from matched image point features. This technique computes a homography estimate that minimizes an appropriate cost function defined on matching points (currently either non-symmetric transfer error, symmetric transfer error, Sampson error or reprojection error) and includes robust regression techniques for coping with outliers.
Apart from fully projective (i.e. 8 DOF) homographies, homest can also estimate affine homographies whose third row is fixed to [0, 0, 1] and thus depend upon 6 parameters. An affine homography is a good approximation of image motion when a large focal length lens is employed or when the point matches used for estimating it originate from a small image area. In such cases, the estimation of an affine homography can be more stable compared to estimating a fully projective homography. When estimating affine homographies, the third step of the algorithm outlined above is omitted since for them, the algebraic error equals the geometric one.
What's New in This Release:В· This release has the ability to estimate affine homographies in addition to fully projective ones.
В· A Matlab MEX interface has been added.
System Requirements:No special requirements.
Program Release Status:
Program Install Support: Install and Uninstall