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Accession Number N20130011120
Title Visible Contrast Energy Metrics for Detection and Discrimination.
Publication Date Feb 2013
Media Count 15p
Personal Author A. Ahumada A. Watson
Abstract Contrast energy was proposed by Watson, Robson, & Barlow as a useful metric for representing luminance contrast target stimuli because it represents the detectability of the stimulus in photon noise for an ideal observer. Like the eye, the ear is a complex transducer system, but relatively simple sound level meters are used to characterize sounds. These meters provide a range of frequency sensitivity functions and integration times depending on the intended use. We propose here the use of a range of contrast energy measures with different spatial frequency contrast sensitivity weightings, eccentricity sensitivity weightings, and temporal integration times. When detection threshold are plotting using such measures, the results show what the eye sees best when these variables are taken into account in a standard way. The suggested weighting functions revise the Standard Spatial Observer for luminance contrast detection and extend it into the near periphery. Under the assumption that the detection is limited only by internal noise, discrimination performance can be predicted by metrics based on the visible energy of the difference images.
Keywords Contrast
Frequency measurement
Frequency ranges
Visual perception
Weighting functions

Source Agency National Aeronautics and Space Administration
NTIS Subject Category 95E - Life Support Systems
57A - Anatomy
Corporate Author National Aeronautics and Space Administration, Moffett Field, CA. Ames Research Center.
Document Type Technical report
Title Note N/A
NTIS Issue Number 1320
Contract Number N/A

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