High Dynamic Range Visual Difference Predictor (HDR VDP) is a perceptual metric that can predict whether differences between two images are visible to the human observer or not.
High Dynamic Range Visible Difference Predictor (HDR-VDP) can work within the complete range of luminance the human eye can see. An input to our metric is a high dynamic range (HDR) image, or an ordinary 8-bits-per-color image, converted to the actual luminance values.
The proposed metric takes into account the aspects of high contrast vision, like scattering of the light in the optics (OTF), nonlinear response to light for the full range of luminance, and local adaptation.
Visual Difference Predictor for HDR images (HDR-VDP) has two unique advantages: firstly, the metric works with a full range of luminance values that can be meet in a real word (HDR images), and secondly, the complete source code offered for free.
The human visual system is too complex to model it reliably, so it can not be expected that an objective metric will match in 100% our perception. However, HDR VDP should make correct predictions in majority of the cases. If it does not, this may indicate that the wrong parameters are used.
The default parameters work for natural images and the 19" display of the resolution 1280x1024 observed from 0.5m distance.
