iat_eccIC implements the inverse-compositional version of ECC image alignment algorithm [1]. It computes the geometric transformation that should be applied to IMAGE in order to get an image similar to TEMPLATE. The optimum transformation is the one that maximizes the Enhanced Correlation Coefficient ([1]) between TEMPLATE and warped IMAGE. It is more efficient than the forwards-additive version (function: iat_ecc) at the cost of lower accuracy (see [1] for comparison)

Input arguments:

IMAGE The image that must be warped in order to be similar to TEMPLATE
TEMPLATE The target image
PAR A struct of parameters with fields:

PAR.iterations: the number of algorithm’s iteration (default:50)

PAR.levels: the number of levels for multi-resolution execution (default: 1)

PAR.transform: the type of geometric transformation. Valid strings:
‘translation’, ‘euclidean’, ‘affine’, ‘homography’ (default: ‘affine’)

PAR.initwarp: the initial transformation. Default warps:
translation: zeros(2,1)
euclidean: [eye(2) zeros(2,1)]
affine: [eye(2) zeros(2,1)]
homography: eye(3)

Output arguments:

WARP The final estimated transformation
RHO The final correlation coefficient between template and final warped image


[1] “G.D.Evangelidis, E.Z.Psarakis, Parametric Image Alignment using Enhanced Correlation Coefficient, IEEE Trans. on PAMI, vol.30, no.10, 2008″


Back to Index