``zero lo voxels'' -- zero out dim voxels

purpose:

Zero out all voxels less than a user-preset gray-scale cutoff.

input:

An 8-bit volume.

output:

An 8-bit volume.

parameters:

Default parameters menu is

upper threshold = 0
* input from vol # = 0
* copy output to vol # = 0
*

comments:

1. A very fast function.

Updated: Fri May 19 14:39:07 CDT