reclassify nodata values surrounded by actual values

Discussion created by DennisJongsomjit on Apr 20, 2011
Latest reply on Apr 25, 2011 by DennisJongsomjit
Hi everyone,

I have a complex raster which has nodata values within it.  I want to be able to extract the areas of nodata within it but not the nodata values that surrounds the grid (all around the extent).  The simplest example would be a donut.  I want to pull out the donut hole (perhaps by converting it to ones) but leave the area outside the donut as nodata. 

If I do a simple reclassify of nodata, all the holes and the entire area around the grid gets converted.  I don't have a raster mask I could use to pull out these nodata values. 

Anyway to do this in spatial analyst???