See the gallery of stimuli.
The data set recreates the stimuli used for the contrast masking measurements described in: John M. Foley, "Human luminance pattern-vision mechanisms: masking experiments require a new model," J. Opt. Soc. Am. A 11, 1710-1719 (1994). link. The detection thresholds were read from Figure 3b, data for KMF. Stimuli dimensions have been changed so that all images are square and cyclic.
The stimuli contain the detection thresholds for a Gabor patch in the presence of a masking signal. The masking signal has the same frequency as the Gabor patch. The orientation of the masking signals is 0 deg (the same orientations as the Gabor), 45 deg or 90 deg.
This is the revision of the metric described in detail in the paper "HDR-VDP-2: A calibrated visual metric for visibility and quality predictions in all luminance conditions" (doi). It shares many similarities with VDP'93 and HDR-VDP, as it was inspired by these metrics, but the functionality is much extended and individual components are thoroughly revised. Note that the model parameters for this revision are different than the parameters included in the supplementary materials of the paper. Refer to the project web-page for the latest code and parameter values.
Revision 2.1 fixes an important bug that caused the nCSF to remain fixed below 1 cd/m^2. To extend the operational dynamic range, the CSF was measured at additional luminance level of 0.002 cd/m^2. The CSF was also measured for all observers, resulting in a more accurate CSF function fit. The predictions are improved for majority of data sets.