2. The system of claim 1 , extrema labels comprise at least one of a bottom line, a baseline, a midline, and a top line.
2. The system of claim 1 , extrema labels comprise at least one of a bottom line, a baseline, a midline, and a top line. 3. The system of claim 2 , further comprising an “other” extrema label that is applied to extrema points that do not fit into at least one of the bottom line, baseline, midline, and top line classifications.