Curt, I'm finally back in the US after 3 years in Baghdad. I'm living down in Olympia and working at Ft. Lewis. Xastir with DRGs was a definite winner last week when I was running all over the range trails at YTC.
I did a bit more googling and found "geotiffcp" which is exactly like "tiffcp", but for geotiffs. DOH!!! I guess I should have looked a bit harder. I can download the unmodified files, but the ones I tried didn't seem to tile together properly. I've got another trip coming up next week. Hopefully I'll have some downtime at the hotel to try a few different combinations of "geotiffcp". When you say the Xastir code is written to handle lines, do you mean scanlines are strips as defined in the tiff/geotiff spec? I should be much more active again now that I'm back in CONUS. 73 N5VFF - Brian On Thu, May 29, 2008 at 10:09 PM, Curt, WE7U <[EMAIL PROTECTED]> wrote: > On Thu, 29 May 2008, ZPO wrote: > >> I'm having an issue using the WA clipped DRGs from - >> http://rocky2.ess.washington.edu/data/raster/drgclip/index.html - . > > >> Some of the DRGs load fine, but the majority (especially the 24Ks) >> give an error of "compression algorithm does not support random >> access". > > Such is the way of the world with modified DRG's... At least you > didn't run into MrSID compressed -and- clipped DRG's. > > >> Based on my reading it appears the correct answer is to reprocess the >> files through TIFFCP and convert them. I'm unsure whether I should >> convert them to strips or tiles. It looks like scanline format is out >> since it doesn't allow random access when using compression. Between >> strips and tiles, is there a preference on which Xastir can process >> more efficiently for pan/zoom/update operations? At first glance I'm >> guessing tiles would be the most efficient. Along with the goes the >> question of recommended tile size. 16? 32? 64? 128? > > The Xastir geotiff code is written to handle lines, not tiles. > > I see two options: > > 1) Find another source for unmodified DRG's. > > 2) Do a Google search through the Xastir list to find the > parameters you need to convert those DRG's to. > > Regarding #1: Where are you at? I have the complete set of WA > DRG's, unmodified. I lent out a set of CD's and a set of DVD's to > one Xastir user in Everett. I have another DVD here at home > somewhere, and another set of CD's at work. I'd rather keep my > hands on one set of each, but the guy I lent the other sets to > should be done by now. > > Another possibility is that you might live near one of the people > I've lent them to before and can copy the DVD's, CD's, or files off > their hard drive. There are at least 4 or 5 people around mostly > western WA that should have them. > > Yet another possibility: If you're near UW you should be able to go > to the library on campus and copy the CD's. They might have them > online now, not sure. I know they have the DOQQ's online and I've > been able to download a few and convert them for use with Xastir. > > -- > Curt, WE7U. archer at eskimo dot com > http://www.eskimo.com/~archer > Lotto: A tax on people who are bad at math. - unknown > Windows: Microsoft's tax on computer illiterates. - WE7U. > The world DOES revolve around me: I picked the coordinate system!" > _______________________________________________ Xastir mailing list [email protected] http://lists.xastir.org/cgi-bin/mailman/listinfo/xastir
