A possible linear filtering model to explain White’s illusion at different grating widths

The perceived lightness of a stimulus depends on its background, a phenomenon known as lightness induction. For instance, the same gray stimulus can look light in one background and dark in another. Moreover, such induction can take place in two directions; in one case, it occurs in the direction of the background lightness known as lightness assimilation, while in the other it occurs opposite to that, known as lightness contrast. The White’s illusion is a typical one which does not completely conform to any of these two processes. In this paper, we have quantified the perceptual strength of the White’s illusion as a function of the width of the background square grating. Based on our results which also corroborate some earlier studies, we propose a linear filtering model inspired from an earlier work dealing with varying Mach band widths. Our model assumes that the for the White’s illusion, where the edges are strong and many in number, and as such the spectrum is rich in high frequency components, the inhibitory surround in the classical Difference-of-Gaussians (DoG) filter gets suppressed, so that the filter essentially reduces to a multi-scale Gaussian one. The simulation results with this model support the present as well as earlier experimental results.

A possible linear filtering model to explain White’s illusion at different grating widths

The perceived lightness of a stimulus depends on its background, a phenomenon known as lightness induction. For instance, the same gray stimulus can look light in one background and dark in another. Moreover, such induction can take place in two directions; in one case, it occurs in the direction of the background lightness known as lightness assimilation, while in the other it occurs opposite to that, known as lightness contrast. The White’s illusion is a typical one which does not completely conform to any of these two processes. In this paper, we have quantified the perceptual strength of the White’s illusion as a function of the width of the background square grating. Based on our results which also corroborate some earlier studies, we propose a linear filtering model inspired from an earlier work dealing with varying Mach band widths. Our model assumes that the for the White’s illusion, where the edges are strong and many in number, and as such the spectrum is rich in high frequency components, the inhibitory surround in the classical Difference-of-Gaussians (DoG) filter gets suppressed, so that the filter essentially reduces to a multi-scale Gaussian one. The simulation results with this model support the present as well as earlier experimental results.

The Comprehensive Processing Methods on Reproducing of the Image of Relic on Subtle Levels

Culture relics, as the remains of legacy in the development of human history, are unduplicated. And making the image of relics, therefore, is significant at protecting, studying and appreciating the cultural relics and even promoting the heritage of human civilization. Subtle level of relic image, as the main part for image duplication always reflects original characteristics and texture of the image. The relic’s density is adjusted to the maximum of the visual identification through centering the relics in the image for black and white points calibration. Adjusting tone curve can represent the relic’s texture to satisfy the requirements of the visual artistic appreciation in accordance with the concrete characteristics of the cultural relic’s image. Based on color adjustment, the detail expression and level texture of the relic can be emphasized. Using image processing method furthers refined correction to ensure the whole density of image and equilibrium of the level. Sharpen the image of relics to intensify the subtle level in accordance with Mach Band Effect. These basic principle and method such as level tone and color adjustment combined with the relevant image processing methods is applied comprehensively to the image duplication, which can represent and promote the subtle level of the image as well as the relics’ style with high quality.