Overviews not showing properly for categorical map

[glaroc]

I've generated a COG of a land cover (integer) map and hosted it on the cloud. I used gdalwarp with nearest resampling for the creation of the cog and the overviews. I used pixelValuesToColorFn to assign a distinct color for every land cover category. When loaded in georaster-layer-for-leaflet, there are "holes" of transparency in the map. It appears that the overviews contain interpolated values that don't correspond to one of the values of the raster. If I debug the pixelValuesToColorFn function, I see some values are passed to it that are not on the actual map. When I zoom in to have the tiles at the maximum resolution, all colors are ok.

See this screenshot

When I load the same map from the URL in QGIS, I don't get this problem, at any zoom level.

With v 3.7.2

[DanielJDufour]

Hi. Does this link help? https://github.com/GeoTIFF/georaster-layer-for-leaflet/issues/86#issuecomment-974067073

[glaroc]

Absolutely! It works like a charm now.

I couldn't find a resampling option in the documentation. Is this documented somewhere ?

Thank you!