The brightest region is thresholded out. An 8-bit grayscale volume. Its first column gives the slice-group number and the second gives the threshold computed by the autothresholder for the slice group. Thresholds generally are computed for groups of slices, called slice groups .
Thresholds can go up or down from one slice group to the next.
This mode is useful for situations where the region of interest is weakly separated from the background on a few slices . The majority of the parameters regulate the histogram search procedure. For a particular group of slices, one grayscale histogram is computed. Figure depicts a grayscale histogram and its associated parameters. This restriction only applies to the highest peak.