  Chromatic derivatives and series expansions of bandlimited functions have
recently been introduced in signal processing and they have been shown to be
useful in practical applications. We extend the notion of chromatic derivative
using varying weights. When the kernel function of the integral operator is
positive, this extension ensures chromatic expansions around every points.
Besides old examples, the modified method is demonstrated via some new ones as
Walsh-Fourier transform, and Poisson-wavelet transform. Moreover the chromatic
expansion of a function in some $L^p$-space is investigated.
