The lacunarity of colour fractal images

Lacunarity is a very useful metric for the multi-scale analysis of the images that exhibit fractal properties. For its computation there exist several approaches, the probabilistic algorithm being accepted as the most elegant approach. However, all the existing methods are defined for one dimensional signals or binary images with extension to grey-scale images. We propose a colour expression of the lacunarity based on the probabilistic algorithm for the computation of the fractal dimension. To validate this new approach, we used both synthetic colour fractal images and natural fractal images. We comment our results and spot several issues regarding the interpretation of lacunarity curves, then we conclude.