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Please let me know how to check for the locations of nodata cells in raster images in ArcMap. The raster images has no attribute table.

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    Do you have a spatial analyst license? If so you can use the function IsNull resources.arcgis.com/en/help/main/10.2/index.html#//… followed by raster to polygon resources.arcgis.com/en/help/main/10.2/index.html#//… and select the polygons where GRIDCODE = 1 (null) to find the null cells locations.
    – Michael Stimson
    Oct 16, 2019 at 2:30
  • Thank you for your reply. yes I have licensee. I am wondering if there is a method that I can use to detect nodata locations directly from raster. The raster images with fine resolutions and converting to polygon could take a lot of time
    – user150625
    Oct 16, 2019 at 2:35
  • I don't have ArcMap, but you can make some raster algebra to create a white raster with black pixels where there are nodata values. For example, if nodata value is 0 and the band is A, the algebra may be (A=0)*255.
    – Gabriel De Luca
    Oct 16, 2019 at 2:59
  • Sorry, I edit my previous comment. Also, the formula (A=0) is enough to assign 1 values to nodata and 0 to the rest.
    – Gabriel De Luca
    Oct 16, 2019 at 3:07
  • Thank yo Gabriel for your reply. I am going to try your method, but I will assign value to nodata first.
    – user150625
    Oct 16, 2019 at 3:35

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Yes, you can usually see NoData cells without Spatial Analyst, directly from the raster.

On the Symbology tab, look for the Display NoData As drop down button. This is usually set to no fill/no color. You can change this to a strong color (and perhaps change other symbology for the raster to grays). The no data cells should be easy to spot. Of course, if your no data cells are distributed in tiny clusters around your raster, they may not show well and you would need to use Spatial Analyst to find them.

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