What is the essential difference in the use of these 2 functions, estimateGe​ometricTra​nsform2D and fitgeotrans?

For example, if there are a number of points (n>4) on two images that are projected to get the projection transformation matrix, and the specified parameter is transformationType = 'projective', which function should I choose to use first?

Answer 1

[Kishan Dhakan]

The functions both do pretty much the same job.

'estimateGeometricTransform2D' takes in the input arguments matchedPoints1 and matchedPoints2 which can be specified as either a KAZEPoints object, cornerPoints object, SURFPoints object, MSERRegions object, ORBPoints object, BRISKPoints object, or an M-by-2 matrix in which each row is a pair of [x,y] coordinates and M is the number of matched points.

'fitgeotrans' takes input arguments movingPoints and fixedPoints, which can be only be specified as as an M-by-2 matrix of type 'double' or 'single'.

'fitgeotrans' supports 'nonreflectivesimilarity', 'similarity', 'affine', 'projective', 'polynomial', 'pwl', and 'lwm' as output tforms.

'estimateGeometricTransform2D' supports 'rigid', 'affine', 'similarity' and 'projective' as output tforms. It also provides additional outputs like statusCode and inlierIndex.

To answer your question, since 'projective' is supported in both, if you have KAZEPoints or other such objects, use estimateGeometricTransform2D. If you have [x,y] co-ordinates, you can use either.

[cui,xingxing]

thanks very much!