Appearance of images

Abstract

What makes an image appear to be a veridical representation of a real scene? Knowing what is necessary to produce a "good" image also aids in the design of more efficient compression algorithms. We review our earlier work on video compression and demonstrate the substantial savings and excellent image quality produced by spatial low-pass filtering of most (but not all) of the individual frames. Currently, we work with still images. An example will show that simple filtering can produce unexpected changes in the perceptual interpretation of a complex scene. I will describe and demonstrate a new compression method we are developing based on the assumption that the fine structure in the amplitude domain (and perhaps in phase, as well) can be of minimal importance in conveying the essence of a scene. We find that a complex image can be reproduced surprisingly well by compressing the entire spatial frequency amplitude spectrum to a very small number of terms. © 2008 SPIE-IS&T.