A practical model is proposed for predicting the detectability of targets at arbitrary locations in the visual field, in arbitrary gray-scale backgrounds, and under photopic viewing conditions. The major factors incorporated into the model include: (i) the optical point spread function of the eye, (ii) local luminance gain control (Weber's law), (iii) the sampling array of retinal ganglion cells, (iv) orientation and spatial-frequency dependent contrast masking, (iv) broadband contrast masking, (vi) and efficient response pooling. The model is tested against previously reported threshold measurements on uniform backgrounds (the ModelFest data set and data from Foley et al. 2007), and against new measurements reported here for several ModelFest targets presented on uniform, 1/f noise, and natural backgrounds, at retinal eccentricities ranging from 0 to 10 deg. Although the model has few free parameters, it is able to account quite well for all the threshold measurements. / text
| Identifer | oai:union.ndltd.org:UTEXAS/oai:repositories.lib.utexas.edu:2152/26061 |
| Date | 22 September 2014 |
| Creators | Bradley, Chris Kent |
| Source Sets | University of Texas |
| Language | English |
| Detected Language | English |
| Type | Thesis |
| Format | application/pdf |
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