An extremely basic question: how to extract the list of unique values from a raster?

[aborruso]

Hi,
is there a way to extract the list of the unique values of the band 1 of a geotiff file?
I have WhiteboxTools v2.2.0.

Thank you

[jblindsay]

My first thought was the ListUniqueValues tool, but that tool only works on vector inputs. Instead, you might want to use the RasterHistogram tool. I think it'll likely do what you're looking to do.

[aborruso]

My first thought was the ListUniqueValues tool, but that tool only works on vector inputs. Instead, you might want to use the RasterHistogram tool. I think it'll likely do what you're looking to do.

Hi @jblindsay and thank you very much.

I have tested it. Two notes:

• the output is not machine readable (it's an html, not a JSON, a CSV, ecc.)
• in the output (below an example) I cannot read the pixel values of my band 1 tiff file (these values are five and are 7, 116, 124, 126, 254).

So it doesn't look like what i need.

Thank you again

[aborruso]

but that tool only works on vector inputs

There is a typo

[aborruso]

I think this is another one (what's the repo of the documentation? I could open some PRs)

[jblindsay]

I'll write a ListUniqueValuesRaster tool, which should achieve what you're looking for. Also, thanks for spotting the typos. The one I had already fixed when I wrote my initial response, although I had not spotted the error in AttributeHistogram until now.

[jblindsay]

Just to let you know that I have now committed the ListUniqueValuesRaster tool to the WhiteboxTools Open Core code base:

https://github.com/jblindsay/whitebox-tools/blob/master/whitebox-tools-app/src/tools/math_stat_analysis/list_unique_values_raster.rs

It will be in the next public release of the WhiteboxTools, which likely won't be available until the end of March or April. However, it is available for use today in Whitebox Workflows for Python (WbW):

https://www.whiteboxgeo.com/whitebox-workflows-for-python/

[aborruso]

You are truly kind. Thank you very much!!!