The present invention is a method of processing a digital image that is initially represented by digital data indexed to represent positions on a display. The digital data is indicative of an intensity value Ii(x,y) for each position (x,y) in each i-th spectral band. The intensity value for each position in each i-th spectral band is adjusted to generate an adjusted intensity value for each position in each i-th spectral band in accordance with 1 n = 1 N W n ( log   I i ( x , y ) - log   [ I i ( x , y ) * F n ( x , y ) ] ) , i = 1 , …   , S where Wn is a weighting factor, “*” is the convolution operator and S is the total number of unique spectral bands. For each n, the function Fn(x,y) is a unique surround function applied to each position (x,y) and N is the total number of unique surround functions. Each unique surround function is scaled to improve some aspect of the digital image, e.g., dynamic range compression, color constancy, and lightness rendition. The adjusted intensity value for each position in each i-th spectral band of the image is then filtered with a filter function to generate a filtered intensity value Ri(x,y). To prevent graying of white zones in the image, the maximum of the original intensity value Ii(x,y) and filtered intensity value Ri(x,y) is selected for display.

Title
Method of improving a digital image having white zones
Application Number
9/888816
Publication Number
20030026494
Application Date
June 25, 2001
Publication Date
February 6, 2003
Inventor
Zia Ur Rahman
Williamsburg
VA, US
Daniel J Jobson
Newport News
VA, US
Glenn A Woodell
Newport News
VA, US
Agent
Peter J Van Bergen Esq
VA, US
Assignee
Science and Technology Corporation
IPC
H04N 09/64
G06T 05/00
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