||The visualizer only uses a limited number of colors, so it may display multiple different labels with the same color. If you are running the visualizer, the label number as well as the color of the voxel under the mouse cursor will be displayed at the bottom of the window. For example, there are two dark green cracks in the image but they have different labels.
In the previous example of ambiguity, your labeling of one of the cracks would most likely be discontinuous. This is not an issue.