Matcher
First Claim
1. In the method of matching a set of subject identification points against a set of reference identification points involving a matcher mechanism that employs a difference table, the improvement comprising the steps of:
- optically scanning the surface of an object that is deemed to be a subject input to provide said set of subject identification points substantially unique to the object being scanned,for each line entry on the difference table as a lead entry, providing a group of difference table line entries, limiting each group so provided to no more than one line entry for each of said reference identification points,for each of said groups, providing a quality value determined by a weighted relationship between the relative displacements of the various line entries in the group,selecting the most significant group quality value, andverifying a match between the set of subject points and the set of reference points as a function of the relative magnitude of the most significant quality value as compared to the number of identification points in a first one of said sets.
3 Assignments
0 Petitions
Accused Products
Abstract
In a matcher mechanism for verifying a match of a set of subject points having positional parameters against a set of reference points having positional parameters, the improvement of employing a set of Group tables derived from the difference table. Each line entry on the difference table constitutes a lead entry of a separate Group table. The Group table are overlapping subsets of the entries on the difference table. The members of the Group table are limited to only one line entry representing each reference point. That line entry is the one which is closest to the lead entry on the difference plane. In addition, all line entries within a Group are limited to those that are within a predetermined window on the difference plane around the lead line entry for the group. A quality score is determined for each of the Group tables based on a weighted proximity value between each pair of line entries in the Group involved. The closer a pair of line entries are to each other, the greater will be its weighted score and its contribution to the weighted proximity value for the Group table. That Group table with the greatest quality score is deemed to provide the quality score for the matcher. A match is determined if the value of that quality score exceeds a threshold which is a function of the number of reference identification points. There may also be a requirement that the quality score exceeds some minimum value.
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Citations
49 Claims
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1. In the method of matching a set of subject identification points against a set of reference identification points involving a matcher mechanism that employs a difference table, the improvement comprising the steps of:
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optically scanning the surface of an object that is deemed to be a subject input to provide said set of subject identification points substantially unique to the object being scanned, for each line entry on the difference table as a lead entry, providing a group of difference table line entries, limiting each group so provided to no more than one line entry for each of said reference identification points, for each of said groups, providing a quality value determined by a weighted relationship between the relative displacements of the various line entries in the group, selecting the most significant group quality value, and verifying a match between the set of subject points and the set of reference points as a function of the relative magnitude of the most significant quality value as compared to the number of identification points in a first one of said sets. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30)
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31. A matcher improvement for matching a set of subject identification points against a set of reference identification points employing a difference table, comprising:
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first memory means for storing a set of subject identification points, second memory means for storing the set of reference identification points, differencing means coupled to the outputs of said first and second storage means to provide a set of difference table entries, means for automatically grouping the line entries on said difference table into a series of group table, each line entry on said difference table providing a lead entry for a different one of said group tables, line entries on said difference table being available for inclusion in more than one group table, each of said group tables having no more than one line entry for each of said reference identification points, means to provide a quality value for each group so formed by virtue of a weighted proximity relationship between each pair of entries in a group, means to select the most significant group quality value, and means to verify a match between the set of subject points and the set of reference points as a function of the relative magnitude of the most significant group quality value as compared to the number of identification points in a first one of said sets. - View Dependent Claims (32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49)
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Specification