topic .Tiff is not showing land use classifications (instead showing RGB) in ArcGIS Pro Questions

.Tiff is not showing land use classifications (instead showing RGB)

r2theoozbeck — Tue, 05 Sep 2023 00:26:13 GMT

Hello. I am trying to load rasters into ArcGIS Pro Desktop, but the land use classifications are not appearing; instead I am seeing RGB (Red Green Blue) bands when I load the rasters.

For context, I am using great publicly available 1m by 1m raster land use data by Univ of North Carolina (https://urbanwatch.charlotte.edu/product). Here are the land use classifications:

and here is the image of one of the .tif files when I just open it up on my computer as a photo:

As you can see, there are a variety of colors representing the different land classes. Theoretically, I should be able to load this .tif and then click on an area and uncover the land class.

But when I load in the .tif files, they are showing up as RGB, shown here:

Is ArcGIS Pro Processing the .tif's incorrectly? How can I get these classifications to appear?

Thank you for your support and time.

Re: .Tiff is not showing land use classifications (instead showing RGB)

DanPatterson — Tue, 05 Sep 2023 07:49:55 GMT

Do the rasters have an attribute table you can open?

Raster dataset attribute tables—ArcGIS Pro | Documentation

can you symbolize them using unique classes?

Change the symbology of imagery—ArcGIS Pro | Documentation

Re: .Tiff is not showing land use classifications (instead showing RGB)

Luke_Pinner — Tue, 05 Sep 2023 08:19:35 GMT

I downloaded a couple. They're definitely 3 band RGB (tested with GDAL and QGIS as well) with no attributes. I think it's just a poor choice of output format by the authors.

However, it's a very simple classification:

255,0,0 = Building

133,133,133 = Road

128,236,104 = Grass/Shrub

34,139,34 = Tree canopy

etc...

Re: .Tiff is not showing land use classifications (instead showing RGB)

r2theoozbeck — Tue, 05 Sep 2023 16:03:11 GMT

Dear Luke, Thanks for simplifying this problem. Would you recommend that the next step is to consolidate the RGB tiff files into a mosaic, and then supervise classify the pixels of the mosaic? (Not sure if I used the right language in my question..)

So, I mean just input the values for RGB and create a label and color based on the classification. P.S. Did you obtain the pixel values by sort of spot checking? I spot checked by referencing the .tiff images and got these values, similar to you:

255,0,0 = Building

133,133,133 = Road

128,236,104 = Grass/Shrub

34,139,34 = Tree canopy

255, 0, 192 = Parking Lot

0, 0, 255 = Water

255, 255, 255 = Other

128, 0, 0 = barren

255, 193, 37 = Agriculture

Re: .Tiff is not showing land use classifications (instead showing RGB)

Luke_Pinner — Wed, 06 Sep 2023 03:45:21 GMT

Another way would be to Combine (Spatial Analyst) the 3 bands.

You need to add them to the map (or tool) separately, not as the tif. e.g.

The output will contain the RGB values as fields. You can then add a class field which you can update from the known RGB values: