In the docs for GrowCutComponents[] there are many examples of masks, but I don't know how to make one for myself. I suppose they are using the drawing tools in some way (which I have never used), but a straightforward application of it gave this error:
Are there any examples of how to make a marker mask? Perhaps in a tutorial or in the refs for another symbol?



Binarizethe marker image, to make sure it's not antialiased $\endgroup$