H-Transform
A 2-D generalization of the Haar Transform which is used for the compression of astronomical images. The algorithmconsists of dividing the 
image into blocks of 
pixels, calling the pixels in the block 
,
, 
, and 
. For each block, compute the four coefficients
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Construct a
image from the 
values, and repeat until only one value remains. The H-transformcan be performed in place and requires about 
additions for an 
image.See also Haar Transform
References
Capaccioli, M.; Held, E. V.; Lorenz, H.; Richter, G. M.; and Ziener, R. ``Application of an Adaptive Filtering Technique to Surface Photometry of Galaxies. I. The Method Tested on NGC 3379.'' Astron. Nachr. 309, 69-80, 1988. Fritze, K.; Lange, M.; Möstle, G.; Oleak, H.; and Richter, G. M. ``A Scanning Microphotometer with an On-Line Data Reduction for Large Field Schmidt Plates.'' Astron. Nachr. 298, 189-196, 1977. Richter, G. M. ``The Evaluation of Astronomical Photographs with the Automatic Area Photometer.'' Astron. Nachr. 299, 283-303, 1978. White, R. L.; Postman, M.; and Lattanzi, M. G. ``Compression of the Guide Star Digitised Schmidt Plates.'' In Digitised Optical Sky Surveys: Proceedings of the Conference on ``Digitised Optical Sky Surveys'' held in Edinburgh, Scotland, 18-21 June 1991 (Ed. H. T. MacGillivray and E. B. Thompson). Dordrecht, Netherlands: Kluwer, pp. 167-175, 1992.
- Prime Algebraic Number
- Prime Arithmetic Progression
- Prime Array
- Prime Circle
- Prime Cluster
- Prime Constellation
- Prime Counting Function
- Prime Cut
- Prime Decomposition
- Prime Difference Function
- Prime Diophantine Equations
- Prime Factorization
- Prime Factorization Algorithms
- Prime Factors
- Prime Field
- Prime Gaps
- Prime-Generating Polynomial
- Prime Group
- Prime Ideal
- Prime Knot
- Prime k-Tuple
- Prime k-Tuples Conjecture
- Prime k-Tuplet
- Prime Manifold
- Prime Number