Bonjour Yves,
I think that gdalwarp is not optimized for saving compressed geotiffs, you would have to do that in a second step. This topic has been addressed in this list not long ago. Anyway, you should be using gdal_translate (with a_srs flag) instead for this task, as you are just adding georeferencing information, not re-projecting the data. something like gdal_translate -co "COMPRESS=PACKBITS" -co "PHOTOMETRIC=MINISWHITE" -co "NBITS=1" -a_srs "EPSG:2154" input.tif output.tif Etienne ----- Original Message ----- From: Yves Jacolin <[email protected]> To: gdal-dev <[email protected]> Cc: Sent: Tuesday, August 30, 2011 8:22:46 AM Subject: [gdal-dev] GTiff optimisation Hello, I am converting GTiff to GTiff in order to add projection and georeferencing information in the header. I am using gdalwarp with some flags, mailny -co flags. I have some question about this. Here is my command line: gdalwarp -co "COMPRESS=PACKBITS" -co "PHOTOMETRIC=MINISWHITE" -co "NBITS=1" - s_srs "EPSG:2154" -t_srs "EPSG:2154" input.tif output.tif 1. File size: input.tif and output.tif have different file size, output file is 50 % bigger than the input file. Is it normal? 2. If I use gdalinfo on my output file, I have no information about MINISWHITE parameter while I have it in the input file. Am I using this creation option correctly? This issue could be related to the first item? 3. I also have a "AREA_OR_POINT=Area" item in my output from gdalinfo, what does it means? gdal version: GDAL 1.7.3, released 2010/11/10 thanks, Y. -- Yves Jacolin http://yjacolin.gloobe.org _______________________________________________ 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
