Using entropy to determine the roundness of rock particles

A number of subjective and objective methods have been proposed to determine the roundness of rock particles, roundness being one of three properties describing the shape of a particle. The objective methods are mainly based on the Fourier transform. In this paper alternative methods based on the Emlen (1973) and entropy measures of inequality are proposed. Furthermore the use of the Kullback-Leibler distance to determine roundness was also investigated. These methods were compared with that proposed by Diepenbroek et al. (1992).