05724456 is referenced by 243 patents and cites 10 patents.

A system and method for processing a digital image signal which represents an image can be made to optimally map luminance values versus a tonal reproduction capability of a destination application. Specifically, the system includes a device for partitioning the image into blocks, then combining certain blocks into sectors. An average luminance block value is determined for each block and a difference is determined between the maximum and minimum average luminance block values for each sector. If the difference exceeds a predetermined threshold value, then the sector is labeled as an active sector and an average luminance sector value is obtained from maximum and minimum average luminance block values. All weighted counts of active sectors of the image are plotted versus the average luminance sector values in a histogram, then the histogram is shifted via some predetermined criterion so that the average luminance sector values of interest will fall within a destination window corresponding to the tonal reproduction capability of a destination application.

Title
Brightness adjustment of images using digital scene analysis
Application Number
8/414750
Publication Number
5724456
Application Date
March 31, 1995
Publication Date
March 3, 1998
Inventor
Andrew K Juenger
Hudson
MA, US
James R Boyack
Waltham
MA, US
Agent
Robert A Sabourin
Assignee
Polaroid Corporation
MA, US
IPC
H04N 7/133
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