This dataset is courtesy of Graham Knott, EPF Lausanne. It was produced on a FIB/SEM microscope 
and then downsampled by 2 in x and y. It served as an illustration for the synapse detection
method of [Kreshuk et al., PLoS ONE, 2012]. The ilastik project file contains labels for 3 classes:
synapses, membranes and the rest. The labeling aimed to optimize the prediction for synapses. 
