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NASA NTRS · 20040088111

Discriminability measures for predicting readability of text on textured backgrounds

Scharff, L. F.·Hill, A. L.·Ahumada, A. J. Jr·Watson, A. B.
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Abstract

Several discriminability measures were examined for their ability to predict reading search times for three levels of text contrast and a range of backgrounds (plain, a periodic texture, and four spatial-frequency-filtered textures created from the periodic texture). Search times indicate that these background variations only affect readability when the text contrast is low, and that spatial frequency content of the background affects readability. These results were not well predicted by the single variables of text contrast (Spearman rank correlation = -0.64) and background RMS contrast (0.08), but a global masking index and a spatial-frequency-selective masking index led to better predictions (-0.84 and -0.81, respectively). c2000 Optical Society of America.

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NASA Discipline Space Human FactorsNASA Center ARCContrast SensitivityPattern Recognition, VisualDiscrimination (Psychology)Data DisplayComprehensionPsychophysicsAdolescentComparative StudyComputer GraphicsHumanModels, PsychologicalColor PerceptionInternetPredictive Value of TestsAdultHuman EngineeringSupport, U.S. Gov't, Non-P.H.S

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Scharff, L. F., Hill, A. L., Ahumada, A. J. Jr, Watson, A. B.. 2000-02-14. Discriminability measures for predicting readability of text on textured backgrounds. https://ntrs.nasa.gov/citations/20040088111

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