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Image-adapted visually weighted quantization matrices for digital image compressionA method for performing image compression that eliminates redundant and invisible image components is presented. The image compression uses a Discrete Cosine Transform (DCT) and each DCT coefficient yielded by the transform is quantized by an entry in a quantization matrix which determines the perceived image quality and the bit rate of the image being compressed. The present invention adapts or customizes the quantization matrix to the image being compressed. The quantization matrix comprises visual masking by luminance and contrast techniques and by an error pooling technique all resulting in a minimum perceptual error for any given bit rate, or minimum bit rate for a given perceptual error.
Document ID
19940024872
Acquisition Source
Headquarters
Document Type
Other - Patent Application
Authors
Watson, Andrew B.
(NASA Ames Research Center Moffett Field, CA, United States)
Date Acquired
September 6, 2013
Publication Date
January 25, 1994
Subject Category
Computer Operations And Hardware
Report/Patent Number
NAS 1.71:ARC-12015-1
Patent Application Number: US-PATENT-APPL-SN-186366
Patent Number: NASA-CASE-ARC-12015-1
Report Number: NAS 1.71:ARC-12015-1
Accession Number
94N29375
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
Patent
NASA-CASE-ARC-12015-1
Patent Application
US-PATENT-APPL-SN-186366
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