Le mardi 8 novembre 2011 20:36:06, Even Rouault a écrit : > Le mardi 08 novembre 2011 11:40:33, Yves Jacolin a écrit : > > Hello, > > > > I have an issue with one of my project which need some frequent update > > and I need some advice. > > > > We have a dataset of small ECW files (5 300 files from 30 to 300 ko). > > This is not the way I want to manage my data to get good performance > > with MapServer. Too much file, too smal. > > You didn't really say what was the problem with many small files... Why not > putting them in a tileindex, possibly with an additionnal .qix spatial > index ?
It seems there was a performance issue with this files. I though using a lot of small ECW files was not a good practice. Am I wrong? > That will be the by far the easier solution to manage the update which is a > big constraint in your process. > > If you have specific performance problem with the ECW format you could > probably translate those individual files into anothe format (uncompressed > tiff, tiff with jpeg compression for example) ok may be I need to check our performance issue. Thanks, Y. > > All this tiles don't form a regular single tile. I mean some part are > > hole. > > > > Here is my issues after merging all the tiles: > > * we lose extent in the final ECW file > > * we have some black background which is not what expected > > * we need to update this final tiles frequently, and so we need fast > > process :) > > > > ECW format doesn't manage nodata so do it mean that I can't have > > alphaband and so I have no solution to get another background color > > (white or transparent)? > > > > Does exist some flag to save extent in the final ECW ? > > > > Have you some advice in order to get what I want (alphaband, good > > perfomance)? I can change file format if needed. We though to use TIFF > > files with a merge of some of them to get bigger tiles. We can either > > merge all the tiles, and then merge new tile with this final files or > > create tileindex for the bigger tiles. > > > > Any hints, advices? > > > > Thanks! > > > > Y. -- Yves Jacolin _______________________________________________ gdal-dev mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/gdal-dev
