Image discrimination models predict detection in fixed but not random noise.

A J Ahumada; B L Beard

doi:10.1364/josaa.14.002471

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Image discrimination models predict detection in fixed but not random noise.

A J Ahumada·B L Beard

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Abstract

By means of a two-interval forced-choice procedure, contrast detection thresholds for an aircraft positioned on a simulated airport runway scene were measured with fixed and random white-noise masks. The term fixed noise refers to a constant, or unchanging, noise pattern for each stimulus presentation. The random noise was either the same or different in the two intervals. Contrary to simple image discrimination model predictions, the same random noise condition produced greater masking than the fixed noise. This suggests that observers seem unable to hold a new noisy image for comparison. Also, performance appeared limited by internal process variability rather than by external noise variability, since similar masking was obtained for both random noise types.

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Discrimination, Psychological Forecasting Humans Perceptual Masking Photic Stimulation Random Allocation Visual Perception NASA Center ARC NASA Discipline Space Human Factors Journal Article Research Support, U.S. Gov't, Non-P.H.S.Research Support, U.S. Gov't, P.H.S.

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A J Ahumada, B L Beard. 1997. Image discrimination models predict detection in fixed but not random noise.. https://doi.org/10.1364/josaa.14.002471

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