TIFFReadDirectory warnings when reading GeoTiff with QPixmap :: load ()

Question

I have a geotiff file that I upload to QPixmap with QPixmap :: load (). I get the following warnings printed on the console several times. However, direct use of libtiff opens it without warning.

Any ideas on how to alleviate these unsightly warnings in QT?

TIFFReadDirectory: Warning, foo: unknown field with tag 33550 (0x830e) encountered. TIFFReadDirectory: Warning, foo: unknown field with tag 33922 (0x8482) encountered. TIFFReadDirectory: Warning, foo: unknown field with tag 34735 (0x87af) encountered. TIFFReadDirectory: Warning, foo: unknown field with tag 34736 (0x87b0) encountered. TIFFReadDirectory: Warning, foo: unknown field with tag 34737 (0x87b1) encountered. TIFFReadDirectory: Warning, foo: unknown field with tag 33550 (0x830e) encountered. TIFFReadDirectory: Warning, foo: unknown field with tag 33922 (0x8482) encountered. TIFFReadDirectory: Warning, foo: unknown field with tag 34735 (0x87af) encountered. TIFFReadDirectory: Warning, foo: unknown field with tag 34736 (0x87b0) encountered. TIFFReadDirectory: Warning, foo: unknown field with tag 34737 (0x87b1) encountered. 

Thanks!

Answer 1

These are custom tags that can be defined using the libtiff library:
http://www.remotesensing.org/libtiff/addingtags.html

They are probably EXIF ​​tags:
http://www.awaresystems.be/imaging/tiff/tifftags/privateifd/exif.html

These are the famous tags for libtiff:
http://trac.imagemagick.org/browser/tiff/trunk/libtiff/tiff.h#L148

Since the new definitions include type and quantity, you can guess what these tags mean. You can also run exiftool to examine unknown TIFF tags:
$ exiftool -htmldump sample.tif> /tmp/dump.html; firefox / tmp / dump.html