Le samedi 14 novembre 2015 22:26:48, Mutlu Ozdogan a écrit : > Dear Evan > Thank you so much for the input. I actually tried exactly those steps and > unfortunately I still get 0s in the output file. Thank you again
Could you post the result of "gdalinfo -mm your_input_file.tif" and the exact GDAL commands you use ? > Mutlu > > Sent from my iPhone > > > On Nov 14, 2015, at 1:00 PM, Even Rouault <[email protected]> > > wrote: > > > > Le samedi 14 novembre 2015 19:49:02, [email protected] a écrit : > >> Dear All > >> I have a 4-band air photo image in which the 4th band is the NIR band > >> but it has also been designated as an alpha band. It is the geotiff > >> format. For some reason whenever I reproject this file (using gdalwarp) > >> or resize it (using gdal_translate) all four bands of the resulting > >> files have zero values. It is as if the alpha band is being used to > >> mask all band values. Any help reprojecting or windowing this large > >> file without making while retaining all 4 band values would be much > >> appreciated. Thank you > > > > Mutlu, > > > > The issue is probably indeed the NIR band being recognized as an alpha > > band. You can remove the alpha interpretation with : > > > > gdal_translate in.tif tmp.tif -co alpha=no > > rm tmp.tif.aux.xml (or del tmp.tif.aux.xml on Windows) > > > > The removal of tmp.tif.aux.xml is important otherwise the alpha > > interpretation would be kept in this XML file > > > > And then you can gdalwarp this tmp.file with the arguments you need : > > > > gdalwarp tmp.tif ... > > > > Even -- Spatialys - Geospatial professional services http://www.spatialys.com _______________________________________________ gdal-dev mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/gdal-dev
