ericanewton

SOLVED: Problems Reclassifying Rasters

Discussion created by ericanewton on May 20, 2011
Latest reply on May 30, 2011 by ericanewton
I've been working on a solution to this problem for a while now so thought I'd post the workaround that I found.

I am importing landsat bands and attempting to reclassify the DN Values 0-255 into two new classes, for example 0 and 1.  For most bands, using the reclassify function works.  However, for some band files, reclassifying either does not work and I get an error message,

The input raster minimum/maximum (huge number) is out of range.  To ensure a correct reclassification, edit ranges or use a different precision settings in the reclassification dialog box.

Sometimes the reclassify tool works, but my output is incorrect - an image showing vertical lines or bands with values 0 and no data.

I tried to calculate statistics first because I noticed that this file, unlike the other files I worked with, did not have statistics calculated, but when I tried that I get the error message,

Invalid drop item:  One or more dropped items were invalid and will not be added to the control.

My solution:

Build an attribute table for the raster data set.
Build Statistics by clicking the symbology tab "discrete color".
Reclassify the raster by using the tool "reclass by table".  I built the table in the reclassify tool - it's easy there to create and save a table based on your preferences for the reclass function.

This successfully built a correctly reclassed image for me.

Hope this helps someone struggling with the same problems!

Outcomes