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Chock M Cardenas AF Klinger A 《IEEE transactions on pattern analysis and machine intelligence》1984,(4):484-492
The database structure and data manipulation capabilities of a generalized PICture Database Management System (PICDMS) are presented. They are based on a dynamic, stacked-image, logical database structure that uses gridded, rather than topological, data representation. A prototype PICDMS has been designed and implemented. A commercial version is being used as a generator of image processing programs. The system has novel capabilities for nonprogrammer users: it is able to 1) build multiple-variable databases from photographs and other two-dimensional data sources such as maps, drawings, etc., and 2) manipulate such data using simple logical commands. Physical organization and accessing strategies are outlined. A summary of the PICDMS data manipulation capabilities is presented and a subset of operations is illustrated with brief examples. A comprehensive example displays PICDMS capabilities and the programming advantages it possesses over other approaches. 相似文献
996.
Research on machine recognition of handprinted characters 总被引:5,自引:0,他引:5
Mori S Yamamoto K Yasuda M 《IEEE transactions on pattern analysis and machine intelligence》1984,(4):386-405
Machine recognition of handprinted Chinese characters has recently become very active in Japan. Both from the practical and the academic point of view, very encouraging results are reported. The work is described systematically and analyzed in terms of so-called feature matching, which is likely to be the mainstream of the research and development of machine recognition of handprinted Chinese characters. A database, ETL8 (881 Kanji, 71 hirakana, and 160 variations for each category), is explained, on which many experiments were performed. Recognition rates reported using this database can be compared, and so somewhat qualitative evaluation of these methods is described. Based on the comparative study, the merits and demerits of both feature and structural matching are discussed and some future directions are mentioned. 相似文献
997.
An extremum principle is developed that determines three-dimensional surface orientation from a two-dimensional contour. The principle maximizes the ratio of the area to the square of the perimeter, a measure of the compactness or symmetry of the three-dimensional surface. The principle interprets regular figures correctly and it interprets skew symmetries as oriented real symmetries. The maximum likelihood method approximates the principle on irregular figures, but we show that it consistently overestimates the slant of an ellipse. 相似文献
998.
Contextual template matching: a distance measure for patterns with hierarchically dependent features
Ben-Bassat M Zaidenberg L 《IEEE transactions on pattern analysis and machine intelligence》1984,(2):201-211
Contextual template matching refers to situations where the feature sets of the two templates under consideration may not be identical, but are rather contingent on the context within which these templates are observed. This paper addresses context-dependent template matching where the relevancy of certain features to a given object is contingent on the value of higher level features. In such situations portions of the patterns for two objects X and Y may not be comparable, and therefore classical distance measures are not applicable. A framework for describing pattern spaces with hierarchically dependent features-named conditional pattern spaces (CPS)-is presented, and a distance measure for comparing objects in a CPS is developed and illustrated on archaeological objects. This measure satisfies several desired properties of distance measures, such as the metric requirements. 相似文献
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