Making NoData pixels transparent on Image Service / Image Layer

[JustinOdell]

Hi all,

I have published an orthomosaic as an Imagery Layer / Image Service. The NoData pixels (R 255, G 255, B 255) are displaying as white and surround the image in a rectangular fashion.

Is it possible to make the NoData pixels transparent once the service has been published? Or can this configuration only be done inside of ArcGIS Pro prior to publishing? If it can only be done prior to publishing, what is the recommended workflow? Ideally, I do not wish to export a new raster if it can be helped.

[TonyContreras_Frisco_TX]

You should set up the mosaic dataset properties to specify NoData values before building your overview images, then publish the service. If the service exists already, I would delete it, update the mosaic dataset according to the help page, then rebuild the overviews and republish the service.

[JustinOdell · Accepted solution]

I ended up right clicking on the raster in Catalog and going in to the properties to change the NoData values. Then republished and voila!

[BugPie]

@JustinOdell  Same issue here once I publish to a tiled image service on our Portal. Can you clarify what you changed in the No Data option within the raster referenced in your mosaic dataset? 

Did you enter 255,255,255 and then click compute or just select OK? 

[JustinOdell]

Hi @BugPie I believe I queried the NoData pixels in ArcGIS Pro to identify what values they were. In my case they were 255 for all bands. Then in ArcCatalog I went to the properties of the image and edited the NoData pixels such that 255 was the value for all bands. I was then able to publish as an Image Service without issue. I did not click the compute button, but I have noticed when I do this I curiously receive 256 for all 4 bands.

[Ross_1]

Is anyone aware of a way to to do this using a value range instead of just one value? I need to make values from 221 to 255 invisible, but I have not been able to find a way.