See the gallery of stimuli.
This data set was measured to demonstrate the effect of CSF flattening in complex images. Gabor patches from 4 to 16 cpd were superimposed on an actual image (portrait) in three different regions: the region with almost no masking (hair), with moderate masking (face) and with strong masking (band). The hair region has almost no masking because the pixel values are clamped at 0. Note that also the luminance varies greatly between these three regions.
The thresholds were measured in the 4-alternative-forced-choice experiment, in which all four images were shown side-by-side. The measurement procedure was the same as for the "Contrast sensitivity for wide luminance range" data set.
This is the Visual Difference Predictor for High Dynamic Range Images, C++ implementation from http://www.mpi-inf.mpg.de/resources/hdr/vdp/index.html, version 1.7
The metric is an extension of the VDP'93 metric that can better handle high dynamic range images. HDR-VDP includes, in addition to the VDP'93 feature set, a model of glare (intra-occular light scatter), photoreceptor response (single luminance channel) and the CSF that adapts locally to the pixel luminance.
The algorithm is described in: R. Mantiuk, S. Daly, K. Myszkowski, and H.P. Seidel. "Predicting visible differences in high dynamic range images: model and its calibration." In Human Vision and Electronic Imaging, 204-214, 2005.