**fScan Reference Manual, Chapter 2 (CmdLineOptions:Expr): Peak**
===== Peak -- find local maxima/minima =====
 **usage:  -e peak minval flag**\\

The PEAK command compares the intensity value of each voxel with the intensities of its 26 immediate neighbors. It results in a map image, in which each new voxel is a flag (see below).

FLAG:\\
 1 - only local extreme values\\
 2 - consider negative peaks as well\\
 4 - save peak locs as ROI points

Return values (combined as bitflag):\\
 1 - has lower neighbor (or higher if neg)
 2 - has equal neighbor
 4 - has higher neighbor (but not if FLAG&1)

**See Also:**\\
[[jvs:fscan:manual:chapter2:expression:gradient|Gradient]],
[[jvs:fscan:manual:chapter2:expression:segment|Segment]],
[[jvs:fscan:manual:chapter2:expression:descend|Descend]]

[[jvs:fscan|fScan Home]], 
[[jvs:fscan:manual|fScan Manual]], 
[[jvs:fscan:manual:chapter2|CmdLineOptions]], 
[[jvs:fscan:manual:chapter2:expression|Expression Command]], 
[[jvs:fscan:manual:help|Manual Help]]