Image Reproduction with Compensation of Luminance Adaptation

Ufuk Çelikcan, Sami Arpa, Tolga Çapın

Overview of our approach. (a) The input image is converted to its spectral representation within the desired wavelength ranges. (b) The photopic and scotopic luminance responses of the image are estimated by integrating the spectra against respective standard luminosity curves. (c) Input image and the photopic and scotopic responses are fed into the optimization to acquire the retargeted image.

We introduce an image reproduction model that retargets colors for printing purposes to ensure similar luminance perception under photopic and scotopic vision. Our model is based on the physiological functioning of the rod and cone cells in the retina in varying lighting conditions, so that the human visual system exhibits responses akin to a printed output of the model for different illumination levels. Prior to retargeting, digital color images are converted to spectral representations and their photopic and scotopic luminance responses are obtained. The color retargeting is realized by optimizing our compensation function over the color space. In addition, we present a spatially varying operator to enhance the color coherence over salient regions. Reproduction results demonstrate substantially decreased difference between the two luminance responses. Further, it is validated through psychophysical evaluation that our model on average provides superior recognition rates in dark environments, while keeping the noticeable differences in aesthetic appeal acceptable in well-lit environments.

Pre-Print Version
- main paper
- supplementary material

Final Version

Purkinje Shift, Scotopic Vision, Color Appearance, Image Reproduction