Scale and frequency in texture analysis

Goes back to the earliest models of texture, in which texture consists of a texture element, arranged spatially according to some placement rule. In the simplest cases, the placement may be exactly periodic, giving a texture whose spectrum is harmonic or purely random, in which case the spectrum will be continuous. In either case, the spectral envelope is completely determined by the texture element, or prototype. In effect, these two rules represent the extreme ends of a spectrum of irregularity in which more or less variability is allowed in both “what” to place and “where” to place it. The authors investigate how these models might be generalised in a way which increases the representational power without involving excessive computation