IMAGINE Discussions

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Occasional Visitor
Posts: 1
Registered: ‎06-13-2018

Query by color and reassign color value

I would like to change file format from TIF to ECW having no data values to be 0 (rgb color unsigned 8bit).  I converted output data type from unsigned 16 bit to unsigned 8 bit when I imported the TIF file.  The imported image includes a white background and I would like to convert white background pixel value to 0.  It is necessary since I would like to use for web mapping.




TIF import having white background

Technical Evangelist
Posts: 750
Registered: ‎02-02-2016

Re: Query by color and reassign color value

You can convert the white pixels to black using a simple spatial model. You need to change the pixels with a value of 255 to 0. Please review the discussion topic linked below to view an example of the spatial model used to perform this task and information about handing NoData in the Spatial Modeler.


No data 255 to 0




Stephen Bent

Hexagon Geospatial Support