Hi Gaby, > I am retooling an application that is using a home grown “map” interface, > replacing the latter with geotools. > Some of the data comes as georeferenced images. These are created by helper > tools from CSV files, ESRI bin files or NETCDF files. > > All good so far. I can read these files no problem using the > GridCoverageReader. > > All the images produced this way are RGB PNG’s which come with an additional > file with the extension “range" which gives > the range of the physical values represented by each pixel. Without this > information I cannot get pack the physical value at > each pixel (wind velocity, flood depth, that sort of thing)
Actually apart of being quite a hack, I don't think that you can get the real value back in every case, don't you? From the png you get rgb values in 0-255 ranges. What should happen next? A mapping to a physical value? This sounds very strange to me. Not sure what the range file really contains, though. Andrea > Correct me if I am wrong, but I think this is part of the “home grown” > solution. I have never seen anything like this before and > google has no idea either. > I thought that I could get the range of values from getting > GridSampleDimension from GridCoverage2D, but they are not there. > > Am I right to assume that the way the images are being created basically > omits this information from the PNG? > > Going forward, I would like to correct this in our helper tools if possible. > Additionally, I want to create grayscale rasters rather than > RGB rasters, since want to leave the “styling” separate and user > modifiable. > > Tweaking the code to create grayscale raster is a piece of cake, but I still > have to use the extra range file. > > What am I missing? > Thanx > Gaby > > > > ------------------------------------------------------------------------------ > Want fast and easy access to all the code in your enterprise? Index and > search up to 200,000 lines of code with a free copy of Black Duck > Code Sight - the same software that powers the world's largest code > search on Ohloh, the Black Duck Open Hub! Try it now. > http://p.sf.net/sfu/bds > _______________________________________________ > GeoTools-GT2-Users mailing list > GeoTools-GT2-Users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/geotools-gt2-users > ------------------------------------------------------------------------------ Want fast and easy access to all the code in your enterprise? Index and search up to 200,000 lines of code with a free copy of Black Duck Code Sight - the same software that powers the world's largest code search on Ohloh, the Black Duck Open Hub! Try it now. http://p.sf.net/sfu/bds _______________________________________________ GeoTools-GT2-Users mailing list GeoTools-GT2-Users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/geotools-gt2-users
