See the gallery of stimuli.
The data set decribes changes in contrast sensitivity due to the size of the grating. The data is reproduced from Figure 2, open squares (vertical gratings for OL) in the paper: Rovamo J, Luntinen O, Näsänen R. Modelling the dependence of contrast sensitivity on grating area and spatial frequency. Vision research. 1993;33(18):2773-88.
The stimuli are sine-waves bounded by a squared area on a 50 cd/m2 background.
Note that most metrics cannot reproduce the differences between sensitivities to patterns of different spatial frequency. It is not clear what is the reason for that.
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.