idea Easily remove white pixels from georeferenced plan in ArcGIS Pro Ideas

Easily remove white pixels from georeferenced plan

Bud — Thu, 18 Apr 2024 13:45:38 GMT

ArcGIS Pro 3.2.2:

I have a .tiff engineering drawing that I've georeferenced. I want to only see the black lines in the image; I want the white background to be removed so that I can clearly see the ortho beneath the georeferenced image.

I imagine there is a way to remove the white pixels using raster geoprocessing tools. However, raster analysis isn't my area of expertise, and I recall raster editing being fiddly work, so I'm looking for an easier option.

Idea:

A button in the Imagery ribbon to quicklly remove white (and near-white) pixels from the existing image (not a copy/export).

I'm aware I can make the entire image semi-transparent so that I can see the ortho beneath the image. That works to a degree, but the ortho is still somewhat obscured by the semi-transparent white pixels. It would be better if the white pixels were completely removed, improving visibility.

Re: Easily remove white pixels from georeferenced plan

marksm_macomb — Wed, 10 Apr 2024 20:00:26 GMT

With your raster layer selected in the contents pane, click on the "Raster Layer" tab in the ribbon, then play around with these Layer Blend modes, specifically the darkening ones. I think "multiply" will do what you want for a pure white background. Sometimes I have old plans with a more yellow background and a different blend mode is needed for that. No geoprocessing tools needed!

Re: Easily remove white pixels from georeferenced plan

ODWC_GIS — Wed, 17 Apr 2024 14:35:55 GMT

Wanted to Kudo @marksm_macomb, but only the 'new comment' window was active.

Re: Easily remove white pixels from georeferenced plan

CharlesGrant — Wed, 17 Apr 2024 17:49:59 GMT

You can change the primary symbology to Classify (which creates 2 classes); change the color scheme to Black to White; then change the white to No Color. It just leaves the black lines.

Re: Easily remove white pixels from georeferenced plan

Bud — Wed, 17 Apr 2024 19:46:05 GMT

Thanks @marksm_macomb and @CharlesGrant.

@dolson_farmington and @MErikReedAugusta might find this interesting.

Re: Easily remove white pixels from georeferenced plan

Bud — Thu, 02 Jan 2025 23:01:48 GMT

Edit:

@CharlesGrant's Classify option worked too.

Just make a new dynamic greyscale layer using Raster Functions, since Classify only seems to work with greyscale.

Why is Primary Symbology > Classify unavailable for some images?

Re: Easily remove white pixels from georeferenced plan

Bud — Thu, 02 Jan 2025 20:03:27 GMT

@marksm_macomb The multiply trick worked well. Thanks!