2023.12.28 18:59 "Re: [Tiff] EXIF tag writing fails starting with libtiff 4.5.1?", by Sulau

Hi Bob,

would it be possible to share the submitted code, how the TIFF IFD and the EXIF IFD are handled.

Are the error reported below from GraphicsMagick? How to reproduce this error?

Then I could have a look.

Handling such "Customer IFDs" was always a tricky thing, because the TIFF IFD has to be written and re-read from file several times and IFDs have to be switched in the correct way, especially for multi-image TIFF. Some hints about that could be found in the comments of custom_dir_EXIF_231.c and at https://libtiff.gitlab.io/libtiff/functions/TIFFCustomDirectory.html

And between 4.5.0 and 4.5.1 we speed up moving between IFDs for TIFF files having a huge number of IFDs (images) and handling of sub-IFDs.

Regards
Su