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Record Details

Record 10 of 8361
Recursive, in-place algorithm for the hexagonal orthogonal oriented quadrature image pyramid
Author and Affiliation:
Watson, Andrew B.(NASA Ames Research Center, Moffett Field, CA, United States)
Abstract: Pyramid image transforms have proven useful in image coding and pattern recognition. The hexagonal orthogonal oriented quadrature image pyramid (HOP), transforms an image into a set of orthogonal, oriented, odd and even bandpass subimages. It operates on a hexagonal input lattice and employs seven kernels, each of which occupies a neighborhood consisting of a point and a hexagon of six nearest neighbors. The kernels consist of one lowpass and six bandpass kernels that are orthogonal, self-similar, and localized in space, spatial frequency, orientation, and phase. The kernels are first applied to the image samples to create the first level of the pyramid, then to the lowpass coefficients to create the next level. The resulting pyramid is a compact, efficient image code. Here, a recursive, in-place algorithm for computation of the HOP transform is described. The transform may be regarded as a depth-first traversal of a tree structure. It is shown that the algorithm requires a number of operations that is on the order of the number of pixels.
Publication Date: Jan 01, 1989
Document ID:
(Acquired Nov 28, 1995)
Accession Number: 90A39970
Subject Category: CYBERNETICS
Document Type: Conference Paper
Publication Information: (SEE A90-39951)
Publisher Information: United States
Meeting Information: Advances in Image Compression and Automatic Target Recognition; Mar. 30-31, 1989; Orlando, FL; United States
Financial Sponsor: NASA; United States
Organization Source: NASA Ames Research Center; Moffett Field, CA, United States
Description: 7p; In English
Distribution Limits: Unclassified; Publicly available; Unlimited
Rights: Copyright
Imprint And Other Notes: IN: Advances in image compression and automatic target recognition; Proceedings of the Meeting, Orlando, FL, Mar. 30, 31, 1989 (A90-39951 17-63). Bellingham, WA, Society of Photo-Optical Instrumentation Engineers, 1989, p. 194-200.
Availability Source: Other Sources
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