topic Re: Raster Catalog Identify Image's Pixel Value? (And Legend Not Showing?) in ArcGIS API for Silverlight Questions

Raster Catalog Identify Image's Pixel Value? (And Legend Not Showing?)

RyanCoodey — Mon, 01 Nov 2010 21:47:34 GMT

We have a raster catalog served up that contains elevation data. There is a new raster every 24 days with new data and so we use the time slider to scroll through these changes over time, hence the reason they are in a catalog and not standalone.

1) How can I get the pixel value for a spot the user clicks on the map?
a) On a side note, does the identify task even return pixel values for standalone rasters?

2) The catalog layer has a classified renderer... I am using the code from ShapeGIS's legend service and it does not bring any symbology back. I don't see that the different classified ranges are even available in the REST API either. I think I saw that 10.1 server was going to have a legend service. Know if it will show these?

Thanks a lot for any info!

Re: Raster Catalog Identify Image's Pixel Value? (And Legend Not Showing?)

dotMorten_esri — Mon, 01 Nov 2010 22:34:23 GMT

1) Use the ImageServiceIdentifyTask to get pixel values.

2) That legend was never tested with / built for ImageService (you could probably enhance it to do that). It's not 10.1 but 10SP1 that will add legend support. However as far as I know, ImageServices are not supported.

Re: Raster Catalog Identify Image's Pixel Value? (And Legend Not Showing?)

RyanCoodey — Mon, 01 Nov 2010 23:31:35 GMT

Hey Morten, thanks a lot for the reply!

Heres the problem though, I am not using an ImageService, it is a DynamicMapServiceLayer... this is for a few reasons.

- Image Services do not support raster catalogs
- Mosaic Datasets (which are supported as Image Services) do not support applying classified symbology.

Therefor we serve up a map service that contains a raster catalog layer and not an image service.

Now we could apply the classified renderer to all our images and export them out with it and put those in a mosaic dataset, but we have a good amount of these images and if the classification needs to change, then these will all have to be exported again.

I tried using the ImageServiceIdentifyTask against the DynamicMapServiceLayer and got this error: "An unexpected error occurred processing the request."

Thanks for the info on the legend... SP1 is coming out in like a week or so, isnt it? I'll have to check it out. Again, this is not a Image Service though... just a regular map service.

Thanks for the help!