On lundi 12 novembre 2018 08:48:59 CET Robert Coup wrote: > Hi Even, > > On Mon, 12 Nov 2018 at 07:57, Even Rouault <even.roua...@spatialys.com> > > wrote: > > Not completely sure what to do with GDAL 2.3 branch, as it already had > > ZStd > > (if using its internal libtiff copy). I feel it is probably wise to also > > update the modified value of COMPRESSION_ZSTD there to avoid the risk of > > people creating files with the now obsolete tag value ? > > How about: > > 1. Read both values as enabling ZSTD > 2. Output a warning when the old value is encountered > 3. Always write the new value
Yeah, that's just what I have done. But only in 2.3 branch, not in master, as I patched the internal libtiff copy for that, and don't intend to upstream that hack or make the internal libtiff in master diverge from official libtiff. $ gdalinfo ../autotest/gcore/data/byte_zstd.tif Warning 1: TIFFInitZSTD:Value of Compression Tag is 34926, which is the deprecated value for ZStd. Please use the new value of 50000 by recreating/ patching this file. Next GDAL releases won't recognize this file. Driver: GTiff/GeoTIFF Files: ../autotest/gcore/data/byte_zstd.tif [...] Note: if you build GDAL 2.3 with the shiny new libtiff 4.0.10 as external libtiff, those files with 34926 won't be recognized. Even -- Spatialys - Geospatial professional services http://www.spatialys.com _______________________________________________ gdal-dev mailing list gdal-dev@lists.osgeo.org https://lists.osgeo.org/mailman/listinfo/gdal-dev
