Abstract: Disclosed is a method for characterizing the content of a digital image. A component of the method is the homogeneity measure, which calculates a value or values based on the local similarity of portions of a sample area. A further component is a means of optimally adjusting the shape and offset of the local sample area to improve the resulting measure. The homogeneity measure may be applied at a higher level to segment an image, by grouping together larger portions of an image whose sub-components are locally similar. A strongly homogeneous region is a contiguous region composed of elements exhibiting local homogeneity better than that of surrounding elements, and may be applied to identify the scale and other characteristics of a portion of an image. This may be used to facilitate algorithms that separate lighting and texturing information, and in identifying the composition of an image.