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ERDAS IMAGINE, the world’s leading geospatial data authoring system, supplies tools for all your Remote Sensing and Photogrammetry needs.
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How to change the null (NoData) value for a raster image.

by Technical Evangelist on ‎07-17-2017 10:32 AM - edited 4 weeks ago by ParthaR. (3,534 Views)
  1. Start ERDAS IMAGINE and launch the "View/Edit Image Metadata" tool from  Home tab > Metadata dropdown list > "View/Edit Image Metadata" or the "Edit Image Metadata" 
  2. In the Image Metadata dialog go to Edit menu > Set/Clear NoData Value.
  3. Enter the desired NoData (null) value.
  4. Click OK to save the change.

nodata.jpg

Comments
by jhebl
on ‎08-03-2017 06:03 AM

Hi,

I run into problem with this NODATA Handling while working with file that came from GDAL.

NoData within this float type file was set to -3,402823e+38. This value was also the statistic minimum and so it the image could not stretched correctly to visualize the real values in range -85 .... 140.

 

BTW IMAGINE registred the NODATA Value but its suggestion was "-3" while using "Set or Clear NoData Value".

A "Clear NoData" was impossible.

 

Pixel Data request delivered #########.### allways. So more or less a NAN-Value.

 

Finally I solved this with a small Spatial Model requesting all Values Lesser than -100 and setting them to 255 and define 255 as NoData.

Updating the statistics while ignoring 255 delivered acceptable statistic and possibility to stretch the image in the optimal way.

 

Best Regards

Jörg

 

by Technical Evangelist
on ‎09-28-2017 07:24 AM

Probably also worthwhile reviewing this article and its comments if you want to know about "Setting NoData":

 

http://community.hexagongeospatial.com/t5/Spatial-Recipes/Handling-NoData-in-Spatial-Modeler/ta-p/95...