Figure A3. Training set of Ilastik classifier 2 out of 2.

This classifier was applied to 2 out of 27 of the test set images which were of higher brightness and contained lower quality borders than the other test set images. Yellow: class ‘big fibre’, blue: class ‘small fibre’, white: class ‘border’, green: class ‘gap’. (A) First training image. (B) Second training image, which is a section from a full image.