Document LabelObject perimeter computations

[blowekamp]

Update documentation to include a link to the IJ paper:
http://hdl.handle.net/10380/3342

[jhlegarreta]

Thanks Brad. AFAIK the classes are not present in the toolkit: may be the code should be made into a remote module? I could help with that if necessary.

[blowekamp]

The LabelMap framework is in ITK as a Group:
https://github.com/InsightSoftwareConsortium/ITK/tree/master/Modules/Filtering/LabelMap/include

Thanks for offering to help. These classes do need a bit of improvement with documentation. The the data is stored in the objects derived from LabelObject i.e. ShapeLableObject, then there are separate filters which compute the data/attributes i.e. ShapeLabelMapFilter. Also there the filters are re-used in multiple other filters i.e. LabelImageToShapeLabelMapFilter. So it has never been clear where documentation of what the attributes mean and how they are computed should be located.

[jhlegarreta]

@blowekamp 👍 I thought that the classes having to do with the perimeter computation had not been included, but I've just seen that they're in the itk::ShapeLabelMapFilter class. Given that I'm not a heavy user of these classes, I'll just be open to help whenever you request so/when tasks can be split into clearer subtasks.