[gdal-dev] gdalwarp -co COMPRESSION issues

[Maciej Sieczka]

Hi

The bug http://trac.osgeo.org/gdal/ticket/1689 is still present in 1.5.0
+ SVN r13865. In that report I mention that gdalwarp creates compressed
TIFFs 45% bigger than gdal_translate. Recently I've noticed it can even
produce TIFFs 13 times (!) bigger (and more?).

Given an input GeoTIFF of size 21802684 bytes, the command:

$ gdal_translate -co "COMPRESS=DEFLATE" slope.tif slope_gt.tif

produces it's clone, of the same size - OK. However, the command:

$ gdalwarp -co "COMPRESS=DEFLATE" slope.tif slope_gw.tif

creates a file 13x bigger - 299550004 bytes!


Moreover, if the input file is big enough for gdalwarp with compression
to try creating 4GB+ raster, it corrupts the output, yielding errors:

0...O10...20...30...40...50...60...70...80...90ERROR 1:
TIFFAppendToStrip:Maximum TIFF file size exceeded
ERROR 1: TIFFAppendToStrip:Maximum TIFF file size exceeded
ERROR 1: TIFFWriteEncodedStrip() failed.

which I guess should not happen, since BigTIFF is enabled - at configure
I have: "LIBTIFF support: internal (BigTIFF=yes)".


For the above reasons, shouldn't output compression for gdalwarp be
disabled to avoid data corruption and wasting space? Or would fixing
another bug, http://trac.osgeo.org/gdal/ticket/1688, fix the compression
in gdalwarp too?

Maciek
_______________________________________________
gdal-dev mailing list
gdal-dev at lists.osgeo.org
http://lists.osgeo.org/mailman/listinfo/gdal-dev