Hi Cleo, I used
-scale 0 4095 0 255 The reason for the 4095 is that the images actually use only the first 12 bits of the 16 bits (according to the documentation) and 2^12 = 4096. If it was a true 16 bit image I would use 65535 for the 'max from' value. Regards Hanlie 2014-08-22 13:56 MGT+02:00, Cleo Drakos <[email protected]>: > hi Hanlie, > can you tell me what value you put for -scale to convert into 8 bit? > > cleo > > > On Fri, Aug 22, 2014 at 7:02 PM, Hanlie Pretorius < > [email protected]> wrote: > >> Hi Even, >> >> Yes, I quoted the exact message, but it displays in the QGIS interface. >> >> I tried gdal_translate with the -ot and -scale parameters on the >> multispectral image and that worked much better, thanks. >> >> Regards >> Hanlie >> >> 2014-08-21 20:33 MGT+02:00, Even Rouault <[email protected]>: >> > Le jeudi 21 août 2014 08:57:32, Hanlie Pretorius a écrit : >> >> Hi, >> >> >> >> I'm working with a 16 bit SPOT 6 image that I want to convert from 16 >> >> bit pixel depth to 8 bit pixel depth. I say 16 bit, but if I load the >> >> file into Envi, it reports that uses only 12 bits. However gdalinfo >> >> reports 16 bit (see below). >> >> >> >> I've manage to do so on the multispectral image, but the result is >> >> poor colour wise. >> >> >> >> So I split the image into its four bands that is, I now have one image >> >> per >> >> band. >> >> >> >> When I now try to convert to 8 bit, I get a message that says: >> >> "Warning 742327101_R1C1_band1_8bit.TIF not created". >> > >> > Are you quoting the exact message ? I can't find any trace of it in the >> > relevant parts of the source code. Did you check that you have write >> > permissions in the directory where you launch the command ? >> > >> > Anyway for what you want to do you likely need to explore the -scale >> option >> > of >> > gdal_translate. But that's unrelated to the error >> > >> >> >> _______________________________________________ >> gdal-dev mailing list >> [email protected] >> http://lists.osgeo.org/mailman/listinfo/gdal-dev >> > _______________________________________________ gdal-dev mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/gdal-dev
