RE: [mapserver-users] Raster image performance

2011-11-12 Thread Ian Walberg
: fwarmer...@gmail.com [mailto:fwarmer...@gmail.com] On Behalf Of Frank Warmerdam Sent: Friday, November 11, 2011 11:52 AM To: Ian Walberg Cc: mapserver-users@lists.osgeo.org Subject: Re: [mapserver-users] Raster image performance Ian, I am guessing you actually have many files, not just one big one

[mapserver-users] Raster image performance

2011-11-11 Thread Ian Walberg
Does anyone have any experience of how to get the best performance out of raster formats. We have an application which needs to be able to display a number of zoom levels and once we get out to whole earth or continent level the performance is poor. Our assumption is that it is the shrinking of

Re: [mapserver-users] Raster image performance

2011-11-11 Thread Frank Warmerdam
Ian, I am guessing you actually have many files, not just one big one. Is that right? As you zoom out opening many files to accumulate the full image is expensive. Up to some scale it is practical to merge things into one big mosaic tiff with overviews. At some point that can be impractically