Image processing in the human visual system

This work extends the multiplicative visual model to include image texture as suggested by experiments [Campbell, Weisel] linking a low resolution Fourier analysis with neurons in certain parts of the visual cortex. The new model takes image texture into account in the sense that weak texture is accentuated and strong, high contrast texture is attenuated. This model is then used as the basis for an improved image enhancement scheme and an unusually successful method for restoring blurred images. In addition, it is suggested how the model may provide new insights into the problem of finding a quantitatively correct image fidelity criterion. The structure of this model is described in relation to visual neurophysiology and examples are presented of images processed by the new techniques. The research described here also shows how the retinex [Land] can be implemented in a new way which allows the required computations to be carried out on a rectangualr grid.