[gdal-dev] LZW Compression on geotiffs

[Even Rouault]

Le mercredi 01 octobre 2014 15:41:06, Newcomb, Doug a écrit :
> Hi,
> I have a 4 band uncompressed geotiff ( NAIP data for North Carolina, USA)
> that is 193 MB
> I've been going over the compression options for gdal_translate  geotiffs
> and I note the following:
> gdal_translate -of “GTIFF” -co “COMPRESS=PACKBITS” gives me a file that is
> 194MB in size
> gdal_translate -of “GTIFF” -co “COMPRESS=LZW” gives me a file that is 232MB
> in size
> gdal_translate -of “GTIFF” -co “COMPRESS=DEFLATE” gives me a file that is
> 177MB in size
> 
> Of the above  Lossless compression options for geotiff, it seems that
> DEFLATE is the only one actually compressing.
> 
> I'm running gdal 1.11.0 on Ubuntu 12.04.3 64 bit compiled with ./configure
> --with-libz   --with-png  --with-libtiff=internal
>  --with-geotiff=internal   --with-jpeg=internal   --with-openjpeg
> --with-pg=/usr/local/pgsql/bin/pg_config --with-ogr --with-xerces
> --with-geos --with-hdf4 --with-hdf5 --with-poppler=/usr/local/lib
> --with-podofo --with-spatialite --with-netcdf
> 
> Is this expected behavior?

Doug,

Not completely surprising that lossless methods don't work well with 
aerial/satellite imagery.
You may also want to test with -co TILED=YES .

Even

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