topic Re: mosaic to new raster incorrect statistics in ArcGIS Pro Questions

mosaic to new raster incorrect statistics

JessicaDecuir — Mon, 14 Dec 2020 20:41:52 GMT

Hi all -

I'm repeatedly running into a problem using the "mosaic to new raster tool". Whenever I attempt to use this tool, the final raster has the wrong calculated statistics. I'm currently running ArcPro 2.5.2, however I've had this problem with ArcMap as well.

In this particular instance, I have 10 small rasters - they are 1 band, 16 bit unsigned. The calculated min and max values for the mosaic raster are well outside of the range of all the source rasters. I have tried using the "calculate statistics" and "build pyramids" tools, but neither change anything. The actual values of the mosaic raster are correct.

I've noticed that others have had this problem going back several years, but no solution appears to been found.

Re: mosaic to new raster incorrect statistics

DanPatterson — Mon, 14 Dec 2020 21:29:43 GMT

What are the values you are getting?

Any nodata values in any of the rasters?

The output mosaic is the same type as the inputs?

Mosaic To New Raster (Data Management)—ArcGIS Pro | Documentation indicates

You must set the pixel type to match your existing input raster datasets. If you do not set the pixel type, the 8-bit default will be used and your output may be incorrect.

And they do indicate in the help that you should use Mosaic if you want finer control over the input parameters

Mosaic (Data Management)—ArcGIS Pro | Documentation

Re: mosaic to new raster incorrect statistics

JessicaDecuir — Fri, 18 Dec 2020 05:38:58 GMT

The source of error in my case turned out to be a single pixel in one of the rasters that had an anomalously low value that I didn't notice. I also made sure that the pixel type of the output raster matched the input. I will try this when I encounter the problem in the future. Thanks!