implement display of imagery (raster) histograms

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03-09-2018 02:13 PM
Status: Open
DavidHarbor
New Contributor III

When teaching remote sensing or how to classify rasters, I find it is vital that students have access to the histogram of the data either in the dataset or in the current view (both would be helpful). Even in the help for Pro's Stretch Function, a histogram makes it clear how or why a percent clip routine is useful.

From the Stretch help file

Stretch function—ArcGIS Pro | ArcGIS Desktop 

However, it is only possible to see histograms of integer continuous data, albeit poorly, in the symbology pane, but not for floating point or imagery data. 

Thus, in my GIS and Remote Sensing class that now uses Pro, I have to apologize for Pro's lack of functionality and display histograms from other products, for example, showing atmospheric contributions to radiance distributions from ERMapper that we used years ago.

from http://geology.wlu.edu/harbor/geol260/lecture_notes/Notes_rs_haze.html 

Please put a window in the symbology pane (or if not that, at least make a geoprocessing tool or function) that displays a histogram for any raster (continuous, fp, or categorical), single band image (tif, ers, grid), or multiband image (tif, grid, ers, etc).  Optimally, it will have a DRA button that can be turned on such that when the focus changes, the histogram will adjust.

Thanks

David Harbor

Tags (1)
3 Comments
KoryKramer

Hi David,

Do you mean like this:

Right-click on your raster layer > Chart > Histogram.

Histogram—Charts | ArcGIS Desktop 

Does that work for you?  Please let us know.

KoryKramer

Hi david.harbor‌ 

I never heard back from you on this one.  Have you tried the Histogram functionality in Pro and can you let me know if that is what you were looking for?

Thank you.

DavidHarbor

Hi Kory

Thanks for looking into this for me. I was teaching in the field this spring and must not have seen your response then.  I apologize for the delay.

I tried your approach on the computer in the lab where I taught the course and it did not work, but suspected that is because the lab only updates to new version occasionally it was still on 2.0.1.  I do have the "chart" right-click option on my laptop which is now using 2.1.3.  Thanks for your assistance and glad this functionality is now with Pro.  Curiously the help page says that the data has to have an attribute table, but my 8 band tif image doesn't seem to. But it works regardless

An additional question, if I may however.  When I request the chart, I only get the option to use the bands (which show up as R, G and B, sadly, not their source names) displayed in the RGB image.  Any way to access each band without having a display layer for each (which is not too terribly onerous)?

Thanks

David