The default WMTS capabilities document returned by STREAM:RASTER sets the maximum zoom level (i.e. tile matrix) as the zoom level that matches the original resolution of the input imagery. If you have layers with a variety of resolutions that to be displayed on the same map and/or you want to use your STREAM:RASTER layer on a map with more zoom levels; you can request a capabilities document with a custom maximum zoom level to match the tile scheme of your map.
To add these extra zoom levels, add a maxZoomLevel custom parameter to your GetCapabilities request, with an integer value indicating the maximum level that should be returned in the document.
With a custom maxZoomLevel set, STREAM:RASTER performs server-side upsampling for any tile requests beyond the original max zoom of a layer, ensuring you don't see empty space on the map when you zoom in too far.
Many web map libraries and desktop applications can upsample imagery for you when you set the visible range of the layer beyond its original maximum zoom. If your viewer supports it, letting the map perform any upscaling client-side will likely offer the best performance and quality.
Use this server-side option only for clients that don't support client-side upscaling (e.g. ArcGIS's "Classic" Map Viewer).
Example - ArcGIS "Classic" Map Viewer
Scenario: You have published 3-inch aerial imagery to STREAM:RASTER in the common Web Mercator tile scheme. In that tile scheme, your imagery's resolution matches level 21, but your ArcGIS web map has 23 zoom levels. You want to add 2 extra zoom levels in your STREAM:RASTER layers, so the imagery layer is visible all the way down to zoom level 23 in your web map.
When you register your WMTS layer in ArcGIS, use the custom parameters table to add a "maxZoomLevel" parameter, in addition to your API Key, to the URL.
Select "A WMTS OGC Web Service" from the data type dropdown and enter "https://raster.stream.woolpert.io/ogc/wmts/1.0.0/capabilities" as the URL. Then click "Add Custom Parameters".
Click "Add Parameter" to add two custom parameters to your WMTS requests:
- key: Your STREAM:RASTER API Key
- maxZoomLevel: An integer value representing the desired maximum zoom level of the layers (e.g. 23)
Continue to "Get Layers" and add the layer to your map as you normally would. The visible range of the layer will now match the full zoom range of your map.
View STREAM:RASTER Tile Layers in GIS Applications (WMTS)
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