Open hard edged pixel image w/o anti-aliasing

[Linda.R.Smith]

I need to replace data colors in a hard edged pixel image. 

the Images were exported from ArcGIS CC for Maps as an AIX file, saved as an Illustrator .ai file. Since it is a raster image I need to open it in Photoshop to replace the color. 

1. Specified default interpolation. Settings > General/Image Interpolation/Nearest Neighbor 
2. When I open it in Photoshop it anti-aliases despite unchecking the option. 
3. After opened tried Image>Image Size/Resample/Nearest Neighbor (hard edges)   

Images Anti-Alaised in ALL attempts (See screenshots attached)

Had some success when in Illustrator >Image>Export (Legacy) to Gif with limited colors but not fool proof.  

This is data and I NEED precise, hard edge pixels.  This has worked with past versions. Not anymore. Possibly this is a bug/technical issue?

Thank you, Linda

[davescm]

That looks more like jpeg compression artifacts rather than anti-aliasing (which would show mainly of diagonals). Did you use compression when you saved the AIX?

https://pro.arcgis.com/en/pro-app/latest/help/sharing/overview/aix-export.htm

Dave

[D Fosse]

Agreed, but just a general observation: If this is a pixel image to begin with, opening at native original size will never cause anti-aliasing or blurring of any kind. Each pixel will just open as it was saved.

Resampling causes blurring. Make sure it isn't resampled.

But if it was saved with jpeg compression, which may be the case here, you get jpeg artifacts. Don't use jpeg for this.

[Linda.R.Smith]

@davescm and @D Fosse Thank you for your response.

I did not export the .AIX. My instructions going back to Exporting from ArcMap to PDF for going on ~15 yrs.  note "No compression."  (dating myself 🙂) As I've mentioned, this was achieveable using past versions of Photoshop.

Before I ask the person to try to export it again, What I don't understand is the .AIX and .AI documents are hard edged. It's not until I open them in Photoshop where the image anti-aliases despite setting the Nearest Neighbor/hard edged in the system preferences beforehand.

The first attachement, I placed the screenshots (PNG) Images into a pdf. This message included attached the original screenshots. Specifically See: 

• 2. Open.AI file in Illustrator to check-OK.png The image colors are hard edged