Using Workbench Command

FIND EXTREMA IN A VOLUME FILE
   wb_command -volume-extrema
      <volume-in> - volume file to find the extrema of
      <distance> - the minimum distance between identified extrema of the same
         type
      <volume-out> - output - the output extrema volume

      [-presmooth] - smooth the volume before finding extrema
         <kernel> - the size of the gaussian smoothing kernel in mm, as sigma
            by default

         [-fwhm] - kernel size is FWHM, not sigma

      [-roi] - ignore values outside the selected area
         <roi-volume> - the area to find extrema in

      [-threshold] - ignore small extrema
         <low> - the largest value to consider for being a minimum
         <high> - the smallest value to consider for being a maximum

      [-sum-subvols] - output the sum of the extrema subvolumes instead of each
         subvolume separately

      [-consolidate-mode] - use consolidation of local minima instead of a
         large neighborhood

      [-only-maxima] - only find the maxima

      [-only-minima] - only find the minima

      [-subvolume] - select a single subvolume to find extrema in
         <subvolume> - the subvolume number or name

      Finds extrema in a volume file, such that no two extrema of the same type
      are within <distance> of each other.  The extrema are labeled as -1 for
      minima, 1 for maxima, 0 otherwise.  If -only-maxima or -only-minima is
      specified, then it will ignore extrema not of the specified type.  These
      options are mutually exclusive.

      If -sum-subvols is specified, these extrema subvolumes are summed, and
      the output has a single subvolume with this result.

      By default, a datapoint is an extrema only if it is more extreme than
      every other datapoint that is within <distance> from it.  If
      -consolidate-mode is used, it instead starts by finding all datapoints
      that are more extreme than their immediate neighbors, then while there
      are any extrema within <distance> of each other, take the two extrema
      closest to each other and merge them into one by a weighted average based
      on how many original extrema have been merged into each.

      By default, all input subvolumes are used with no smoothing, use
      -subvolume to specify a single subvolume to use, and -presmooth to smooth
      the input before finding the extrema.