Dear scikit-image community: I am trying GLCM functions in scikit-image. http://scikit-image.org/docs/dev/auto_examples/features_detection/plot_glcm.... I wonder whether they can treat images with irregular shapes, such as a circle, an oval, or some more complex forms (not only rectagle). In the "greycomatrix", function: def greycomatrix(image, distances, angles, levels=None, symmetric=False, normed=False): image : array_like Integer typed input image. Only positive valued images are supported. If type is other than uint8, the argument `levels` needs to be set. the "image" seems to be required to be a rectangle. If NAN or NULL values are allowed in the "image", and the function skips treating those "no-data" pixels assigned with NAN or NULL, then we may be able to treat any shapes of image, by filling the pixels outside the boudary with NAN or NULL. However, in the source code of "_glcm_loop" function (https://searchcode.com/codesearch/view/83509141/), all the pixels within the rectangular image are scanned, without permitting "no-data". My questions: 1. Do you know how to treat GLCM in non-rectangular image with scikit-image? 2. If not, do you know any other ways to do that instead of scikit-image? 3. Do you think it is a reasonable idea to change GLCM functions in scikit-image so that they can treat no-data (allowing NAN or NULL)? -- Kenlo Nishida Nasahara Faculty of Life and Environmental Sciences University of Tsukuba, Japan 305-8572 24dakenlo@gmail.com