topic Re: ArcGIS Pro Nibble tool problem in ArcGIS Spatial Analyst Questions

ArcGIS Pro Nibble tool problem

FrankHanssen — Thu, 05 Sep 2019 07:13:56 GMT

I have a wawe intensity raster with gaps (NoData), and I want to Nibble the NoData pixels from neighbouring pixel values (wawe intensity values) in ArcGIS Pro, using a separate sea water mask covering the NoData areas (pixels in dark blue). The two raster are 32 bits floating point rasters and have identical raster statistics, extents and projection. In addition all the required env. variables seems to be correctly defined. The Nibble tools performs well without any error messages. BUT the output is a raster with values from -3.4 to +3.4. The same problem occurs when I use the Focal Statistics tool... same problems with integer rasters, Nibble output 0-255. The floating output raster has the same size 2.8 GB, so there are some data in there.. I have also built new pyramids and calculated raster statistics without any improvements..

Any ideas why this is so, and how to solve this problem?

Best regards,

Frank

Re: ArcGIS Pro Nibble tool problem

Robert_LeClair — Thu, 05 Sep 2019 22:08:01 GMT

A couple questions - what's the output format of your raster dataset? If it's a standalone GRID, try to set the output raster to a file geodatabase format. Also, what is the data in projected or geographic coordinate systems?

Re: ArcGIS Pro Nibble tool problem

FrankHanssen — Fri, 06 Sep 2019 07:33:25 GMT

Hi Robert!

All input rasters are within the same file geodatabase as the output file, and they are all in a projected coordinate system (ETRS 1989 UTM Zone 33N)

Best regards,

Frank

Re: ArcGIS Pro Nibble tool problem

DanPatterson_Retired — Fri, 06 Sep 2019 09:41:31 GMT

Frank, it might be useful to show the input rasters. I presume that you have a basemap on and it doesn't represent the landmass exactly

Re: ArcGIS Pro Nibble tool problem

FrankHanssen — Fri, 06 Sep 2019 10:09:46 GMT

The input rasters are shown in the image above, Wawe intensity (green to red) and the NoData Mask (dark blue) Alle the data is within the coastal area region of interest.

Re: ArcGIS Pro Nibble tool problem

DanPatterson_Retired — Fri, 06 Sep 2019 10:14:54 GMT

The reason I asked is that the nodata mask (dark blue) appears to be at a much finer resolution that the other raster. I guess I was hoping for a zoomed in location to see what was going on

Re: ArcGIS Pro Nibble tool problem

FrankHanssen — Fri, 06 Sep 2019 10:20:28 GMT

Re: ArcGIS Pro Nibble tool problem

FrankHanssen — Fri, 06 Sep 2019 10:21:17 GMT

They both have the same spatial resolution 50 x 50 meters (land pixels in white)

Re: ArcGIS Pro Nibble tool problem

FrankHanssen — Fri, 06 Sep 2019 10:22:51 GMT

The wawe intensity raster is from remote sensing

Re: ArcGIS Pro Nibble tool problem

DanPatterson_Retired — Fri, 06 Sep 2019 10:34:27 GMT

but the wawe intensity, is it a single band raster?

In any event, did you try to change the 3rd parameter PROCESS_NODATA ? instead of the default.

I will flag Steve Lynch‌ who might have better insight on this

Re: ArcGIS Pro Nibble tool problem

FrankHanssen — Fri, 06 Sep 2019 11:37:15 GMT

Yes, both are single band rasters. And I used the 3rd parameter PROCESS_NODATA as I would like to nibble values into the NODATA-pixels of the wawe raster, represented by the associated NNODATA mask. Thanks a lot for helping me with this problem!

Re: ArcGIS Pro Nibble tool problem

FrankHanssen — Fri, 06 Sep 2019 14:01:50 GMT

The only difference between the two raster is that the NoData mask raster is not compressed, whereas the wawe-raster is compressed with LZ77

Re: ArcGIS Pro Nibble tool problem

curtvprice — Sun, 08 Sep 2019 02:45:42 GMT

Frank,

I suggest trying outputting to tiff or grid. Over the years, I have had all kinds of nasty bit depth problems with file geodatabase rasters. I should mention it has gotten better over the years. But, I have found raster processing more efficient and robust when working with file based formats. Map Algebra uses .tif as its intermediate format of raster processing workflows (not fgdb). I will often get my processing done, and then as a final step copy to fgdb if I need it there (carefully setting options for bit depth and nodata).

Re: ArcGIS Pro Nibble tool problem

FrankHanssen — Mon, 09 Sep 2019 12:44:57 GMT

Dear Curtis!

Thanks for advising me to use GRIDs.

I solved the problem (went back to ArcGIS 10.17 as I am still most familiar with that SW).

First I converted all NoData wawe-pixels to 0 to allow the Nibble tool too do the interpolation (within the coastal zone area).
I then used this converted layer as the input raster to the Nibble-tool.
The original wawe-raster (with its NoData pixels) aim as the input raster mask. The Nibble output gave me the intended result, as visualized in the enclosed images.

Best regards,

Frank

Re: ArcGIS Pro Nibble tool problem

FrankHanssen — Mon, 09 Sep 2019 12:46:41 GMT