Hi Mapserver folks! I have these huge (20,000px by 10,000px approx.) aerial images that I want to figure out how to turn into a reletively speedy WMS server.
I've got all the basics down. I mean, it already works, but is really slow. It takes up to a few minutes to generate a single image. I want it to take less than a few seconds. It would be nice if the WMS was as speedy as Google Maps itself, but I do caching outside the context of mapserver to make that happen. I just want to make the WMS fast. It would be nice if there was a completely automated way of speeding up raster map serving. Is there? I think the information I need would fit in the documentation here under Preprocessing-rasters: http://mapserver.gis.umn.edu/docs/howto/raster_data/#preprocessing-rasters I've read through the mapserver performance tips, but I'm running into a few problems. You can follow along in section 10 on that same link. One program I've looked at is gdaladdo: How do I test to make sure overlays are in fact being used? How do I know what levels of overlays to create? How do I systematically test performance so that I know what I'm doing to the images is a good use of my, and my computers processing time? Another method I've looked into is tiling and using the tileindex mechanism of the map file. I haven't found a good tutorial on how to take one image and tile it into a whole bunch of smaller images all while keeping each georeferenced correctly. It would be great if someone could point me in the right direction. The images are in the correct projection already fortunately. So, no need to warp. I wonder if I could reduce the quality of the images slightly to improve performance. Alright... time to watch the super bowl. Enjoy the game and commercials everyone! -- Kyle Mulka Computer Science in Engineering University of Michigan http://maps.kylemulka.com
