The capabilities of the fractional differential approach for enhancing textural features of two-dimensional digital images, involved Lateral Inhibition Principle, the multiform covering templates and algorithms of digital image’s fractional differentiation were discussed. Firstly, the kinetic physical meaning of fractional differential and the relationship between fractional calculus and classical time-frequency analysis were deduced,and used to handle x-y separability of two-dimensional fractional calculus in undemanding conditions. Secondly, the difference of two Gaussians receptive field between fractional and integral differential of digital image was discussed in view of signal processing and biologic vision nerve model respectively. An analysis of its Mach band was also included. Finally, multiform covering templates and a numerical algorithm for computing fractional differential for digital image were discussed. Numerical experiments showed that the textural detail enhancing capabilities of fractional differential-based texture operator are better than that of integral differential-based one for rich-grained digital images.
