WMS WMTS Layers by CM & SC

What is Web Map Service (WMS)?

According to the tutorial page listed above, "this is a better choice for using reference layers as you get access to rich datasets in your GIS without the hassle of downloading or styling the data" (Gandhi 2010). According to Open Geospatial Consortium (OGC Server), WMS attaches an HTTP interface to the geo-registered map images from one or more geospatial databases.

WMS georeferences maps created using .JPEG, .PNG, .TIFF.
Image format matters! Use the guide below depending on what kind of format you are aiming for…

  • .JPEG > use if you want speed (using in project)
  • .PNG > use if you want quality (printing a map)
  • .TIFF > not good if sending to another person (.JPEG, .PNG are more cross compatible)

Note: if you have mostly vector layers, use .PNG. Imagery? Use .JPEG


What is Web Map Tile Service (WMTS)?

QGIS can also act as a WMTS client. WMTS is an OGC standard for distributing tile sets of geospatial data. QGIS as OGC Data Client. This is a faster and a more efficient way of distributing data than WMS because with WMTS the tile sets are pre-generated and the client only requests the transmission of the tiles and not their production. A WMS request typically involves both the generation and transmission of the data. A well known example of a non-OGC standard for viewing tiled geospatial data is Google Maps.

In order to display the data at a variety of scales close to what the user might want, the WMTS tile sets are produced at several different scale levels and are made available for the GIS client to request them.

  • Begin by clicking the Add WMS layer button inside the toolbar, or through the Layer ‣ Add WMS Layer… menu.
  • The first time you use the WMS feature, there are no servers defined
  • The dialog Add Layer(s) from a Server for adding layers from the WMS server appears. You can add some servers to play with by clicking the [Add default servers] button. This will add two WMS demo servers for you to use, the WMS servers of the DM Solutions Group and Lizardtech. To define a new WMS server in the tab Layers, select the [New] button. Then enter the parameters to connect to your desired WMS server
  • Once the new WMS Server connection has been created, it will be preserved for future QGIS sessions.

References and Resources

  1. Ujaval Gandhi Tutorial: Using Online Data via WMS in Quantum GIS

Credits

Edited by Phuong Tseng