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km_prematchings

$ \bigcirc$Name


km_prematchings Get pre-matching codes of two dictionaries




$ \bigcirc$Command Synopsis


km_prematchings maxError dict1 dict2 matchings



maxError : maximum allowed Hausdorff distance between two codes to be considered as pre-matching

dict1 : dictionary codes of image 1 (Flists)

dict2 : dictionary codes of image 2 (Flists)

matchings : output Flists: for each code of dict1, the indices of the dict2 codes which are closer than maxError in Hausdorff distance




$ \bigcirc$Function Summary


Flists km_prematchings (maxError , dict1 , dict2 , matchings )

float maxError ;

Flists dict1 , dict2 , matchings ;




$ \bigcirc$Description


This module is mainly an auxiliary module for km_match_si and km_match_ai. It computes all pairs of curves that are good candidates to match (pre-matchings). However, it can be used independently from these modules.

dict1 and dict2 contain N1 and N2 normalized codes of pieces of curves of images 1 and 2. To be more precise, dict1 = {$ \mathcal {C}$1i, 0 $ \leq$ i $ \leq$ N1 -1} and dict2 = {$ \mathcal {C}$2j, 0 $ \leq$ j $ \leq$ N2 -1}. Both dictionaries must have been computed using the same MegaWave module (km_createdict_si or km_createdict_ai).

km_prematchings returns an Flists that containts N1 Flist. The i-th Flist contains the indices j of all the codes of dict2 that satisfy dH($ \mathcal {C}$1i,$ \mathcal {C}$2j) < maxError, where dH is the Hausdorff distance.

It should be noted that maxError is a distance between normalized codes and not a distance between curves in the image frame, and typically its value is to be chosen in the range [0.1, 0.3].


For more details, see J.-L. Lisani's PhD dissertation [Lis01] or [LMMM03].




$ \bigcirc$See Also


km_match_ai, km_match_si.


$ \bigcirc$Version 1.0


Last Modification date : Thu Apr 1 16:43:46 2004


$ \bigcirc$Author


Jose-Luis Lisani, Pablo Muse, Frederic Sur






next up previous contents index
Next: km_savematchings Up: Reference Previous: km_match_si   Contents   Index
mw 2004-05-05