Hi list, For your information: today we imported an entire dataset (10 Gb) into Oracle using the ImageMosaic JDBC plugin.
My impressions & recommendations: - When retiling from Geotiff to PNG (or any other supported image format), use gdal_translate to convert Geotiff to <target format> first and gdal_retile second. The quality of the level-tiles is much higher that way. Somehow Geotiff > PNG directly works fine when the tile size was 1024px but the images became extremely (!) gritty when a size of 256px or 512px - looks like some sort of color-depth issue or something. And somehow we got this weird "coloured tv snow" band of pixels on the top of each tile when retiling Geotiff > Geotiff?! - The import to Oracle works like a charm, except that the scripts which the ddl call generates include inserts into the "mosaic" table. Sometimes (so, not all the time) these records are inserted again during the actual import, which causes a primary key violation on the table and the import to crash. - Sometimes the outputted map-image was missing tiles (squared white spaces) - a little panning and they appeared again. I doubt this was because of performance issues because the server and netwerk are pretty quick. Overall, thanks again for the tip - much appreciated. In addition I'll try and take a look at the plugin-code myself to see if I can find cause for the two issues above. Ow, and apologies if this kind of information is inappropratie for this list :) Regards, Robert Simone Giannecchini wrote: > That is really great news :-). > > > Please, keep us posted. > > Simone. > ------------------------------------------------------- > Ing. Simone Giannecchini > GeoSolutions S.A.S. > Owner - Software Engineer > Via Carignoni 51 > 55041 Camaiore (LU) > Italy > > phone: +39 0584983027 > fax: +39 0584983027 > mob: +39 333 8128928 > > > http://www.geo-solutions.it > http://simboss.blogspot.com/ > http://www.linkedin.com/in/simonegiannecchini > > ------------------------------------------------------- > > > > On Thu, Apr 23, 2009 at 1:37 PM, Robert van Drunen > <[email protected]> wrote: > >> Hello Christian and Simone, >> >> Actually it all worked out-of-the-box. I used the description on this page: >> >> http://geoserver.org/display/GEOSDOC/Using+the+ImageMosaic+JDBC+Plugin >> >> to setup the JDBC connection to Oracle, create the metadata scripts and >> load some sample geotiffs using the mosaicjdbc jar. >> >> The only difficulty I had was that Oracle uppercases it's tablenames >> when you query them, so you need them uppercased in gdal commands as well :) >> >> Now it's upto my cliënt to agree with this approach instead of using >> actual Georasters and see what the performance is when we load the >> entire dataset this way. >> >> Thanks for the help, it's much appreciated! >> >> Robert. >> >> Christian Müller wrote: >> >>> To answer the questions >>> 1) Performance >>> I am handling 3 maps with about 8 million tiles , biggest map 4 >>> million tiles , biggest layer consists of 2 million tiles. >>> The tiles are stored in png format. (Compression). Tile sizes are >>> 256x256 and 512x512. >>> The decoding (Decompression) of the tiles is done in a multithreaded >>> manner. Multiple/Multicore CPUs will be used if present. >>> The db lookup to find the right tiles is very fast if you have the >>> proper indexes. Decoding starts when the first tile is fetched, >>> fetching and decoding works like streaming using a queue from the >>> java.concurrent package. >>> Store your tiles as single banded images with a color table. Check >>> with gdalinfo, if you have multiple bands use gdal_merge >>> with the -pct option to produce a big picture. Afterwards apply >>> gdal_retile. >>> You can import the output of gdal_retile. >>> Performance decreases when doing a request with a different CRS, >>> because the whole picture has to be transformed. You will get see a >>> WARNING in the log file. Try to avoid it. >>> Environment: Geoserver running on Linux PPC using DB2 Spatial Extender >>> on an AIX Box >>> 2) >>> If you have to use Oracle Georaster. I agree to Simone. The best would >>> be to implement a special coverage store. >>> 3) At the moment, the plugin is not able to handle rotated or skewed >>> images, but if necessary, I would add this feature. >>> >>> christian >>> >>> >>> >> -- >> ------------------------------------------------------- >> BEng. R.J.M. van Drunen >> Anargistic >> Owner - Software Engineer >> Sint Luciaplein 27 >> 5211 ZR 's-Hertogenbosch >> >> mob: +31 062369319 >> >> http://www.anargistic.nl >> http://www.linkedin.com/in/robertvandrunen >> ------------------------------------------------------- >> >> >> >> ------------------------------------------------------------------------------ >> Stay on top of everything new and different, both inside and >> around Java (TM) technology - register by April 22, and save >> $200 on the JavaOne (SM) conference, June 2-5, 2009, San Francisco. >> 300 plus technical and hands-on sessions. Register today. >> Use priority code J9JMT32. http://p.sf.net/sfu/p >> _______________________________________________ >> Geotools-gt2-users mailing list >> [email protected] >> https://lists.sourceforge.net/lists/listinfo/geotools-gt2-users >> >> > > -- ------------------------------------------------------- BEng. R.J.M. van Drunen Anargistic Owner - Software Engineer Sint Luciaplein 27 5211 ZR 's-Hertogenbosch mob: (+31)623693129 http://www.anargistic.nl http://www.linkedin.com/in/robertvandrunen ------------------------------------------------------- ------------------------------------------------------------------------------ The NEW KODAK i700 Series Scanners deliver under ANY circumstances! Your production scanning environment may not be a perfect world - but thanks to Kodak, there's a perfect scanner to get the job done! With the NEW KODAK i700 Series Scanner you'll get full speed at 300 dpi even with all image processing features enabled. http://p.sf.net/sfu/kodak-com _______________________________________________ Geotools-gt2-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/geotools-gt2-users
