2000.03.17 18:34 "Re: Some CCITT Group 3 TIFFs crash libtiff", by Frank Warmerdam

The problem that your patch addresses may well be related, but the patch doesn't seem to have any affect on my problem TIFFs. They crash just the same.

Jason,

Good news, I have worked out what the bug is. In the last few months the fax3 code was changed to handle files wider (or longer?) than 65536 pixels and part of this was converting the runs arrays from uint16 to uint32.

However, a -1 was used as a special value that used to be used as 65536 which trigger "over the end" code, but as a uint32 it wrapped back to a small number when added to a small number and didn't trigger the code properly. I have added a couple extra tests and now all is well with at least one of your files!

The updated tif_fax3.c code can be found at:

http://gdal.velocet.ca/~warmerda/tif_fax3.c

Let me know if this seems fine, and I will talk to Mike about preparing a new release before too many more people run into the same problem.

Best regards,

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