2007.11.02 20:26 "[Tiff] Recent bug fixes in CVS head", by Frank Warmerdam

2007.12.30 22:20 "[Tiff] libtiff4 - tests failing - TIFF_SETGET_UNDEFINED for some tags", by Frank Warmerdam


I am looking to add some capabilities in libtiff4 (aka CVS head) and I discovered the libtiff/test directory as a nice place to add some tests. However, I discovered that the existing tests do not actually pass.

I investigated, and it seems some tags can't be read (such as TIFFTAG_PIXAR_TEXTUREFORMAT) because even though they have a type of TIFF_ASCII, the set_field_type is TIFF_SETGET_UNDEFINED and this seems to result in the value not being processed.

I find setting the set_field_type to TIFF_SETGET_ASCII seems to resolve the problem and the test passes. But it is not at all clear to me how this is all supposed to work. Is there a reason so many tags defined in tif_dirinfo.c have the set_field_type and the get_field_type fields set to TIFF_SETGET_UNDEFINED? Is there a reason that having the get_field_type field as TIFF_SETGET_UNDEFINED seems to be fine (the field can be written to disk)? Is there some more detailed documentation of how the _TIFFFieldArray structure contents work than the brief blurbs in the structure definition itself?

I'm feeling lost! I've held my changes to tif_dirinfo.c till I get some sort of answer on what I should be doing in the hopes of pursuing a more comprehensive solution.

Best regards,

I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam@pobox.com
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