Re: non rectangular crop

*To*: mathgroup at smc.vnet.net*Subject*: [mg110727] Re: non rectangular crop*From*: Patrick Scheibe <pscheibe at trm.uni-leipzig.de>*Date*: Sat, 3 Jul 2010 08:19:45 -0400 (EDT)

Hi, > is it possible to have a not rectangular image in Mathematica? no. You can of course use SparseArray to create one and therefore you could create an image where you don't have to specify the whole image matrix Image[SparseArray[{{1, 1} -> 0.3, {7, 2} -> 0.5, {9, 9} -> 1}, {10, 10}]] but internally it stores the whole matrix InputForm[%] > I have a lot of images acquired by microscope - they are all squared, > with the circular field of view surrounded by black. > I'd like - for further processing - to crop all the black region > outside the circle. but if the outside of your circular region is black then it is already croped in some way because filters like binarization, blur-filters, segmentation, registration, ... will ignore the black regions. I don't see your concerns. Cheers Patrick