GeoServer altering raster values of multi-band raster WCS request

Question

I'm hosting some NAIP imagery (4-band) through Geoserver and while WMS requests show true pixel values properly, if a WCS request is issued, the raster GeoServer returns has pixel values of nodata where 0 would be.

For instance, where a pixel in the original raster would have RGBI values of 38, 0, 2, 56, the returned raster has values of 38, nodata, 2, 56.

From the logs (Verbose), I can't see any sort of operation being performed (e.g. warp) that would result in an effectively new raster, so I'm not sure what's going on here. No input transparent color is declared in the layer properties. The request looks something like:

.../geoserver/wcs?service=WCS&version=1.0.0&request=GetCoverage&coverage=TEST_RASTER_NAIP&bbox=491592.0,3474409.0,492178.0,3474761.0&crs=EPSG:26912&format=geotiff&width=586&height=352

The result is also the same if I build it using resx and resy instead of width and height.

Answer 1

Turns out it was tied to the output transparent color settings for the layer. Nothing to do with the handling of the wcs request itself. I had set to the output transparent to FFFFFF, which was causing geoserver to set the nodata value of the raster provided from getcoverage to 0. Solved.