Quantitative characterization of particle morphology is very useful in monitoring and control of particulate processes. Morphology descriptors must be invariant with respect to translation, rotation and scaling. Descriptors derived from one-dimensional Fourier transform of particle contour (boundary Fourier transform) and two-dimensional Fourier transform (generic Fourier transform) of image region meet these requirements. Their performances in classifying particles with different agglomeration degrees and in discriminating particles from different manufacture processes were investigated and compared. They work on different morphological information and can play complementary roles in the characterization of particle morphology. To the authors' best knowledge, this is the first report on the application of generic Fourier transform in particle description and classification. (c) 2007 Elsevier Ltd. All rights reserved.