In a preceding study, we investigated the effects of image noise on the perception of image sharpness using white noise, and one- and two-dimensional single-frequency sinusoidal patterns as stimuli. This study extends our preceding study by evaluating natural color images, rather than black-and-white patterns. The results showed that the effect of noise in improving image sharpness perception is more evident in blurred images than in sharp images. This is consistent with the results of the preceding study. In another preceding study, we proposed "memory texture" to explain the preferred granularity of images, as a concept similar to "memory color" for preferred color reproduction. We observed individual differences in type of memory texture for each object, that is, white or 1/f noise. This study discusses the relationship between improvement of sharpness perception by adding noise, and the memory texture, following its individual differences. We found that memory texture is one of the elements that affect sharpness perception.
According to color research, people have memory colors for familiar objects, which correlate with high color preference.
As a similar concept to this, we propose memory texture as a mechanism of texture preference by adding image noise
(1/f noise or white noise) to photographs of seven familiar objects. Our results showed that (1) memory texture differed
from real-life texture; (2) no consistency was found between memory texture and real-life texture; (3) correlation existed
between memory texture and preferred texture; and (4) the type of image noise which is more appropriate to texture
reproduction differed by object.