TIFF and LibTiff Mail List Archive

2001.08.22 18:48 "Manipulating TIFF tags", by Tore Bostrup

I will need to manipulate and add some TIFF tags to an existing Group 4 TIFF. Will it be sufficient to simply move the existing data to accommodate the new entries and potentially changes in the length of values (I realize I have to update (and potentially move) the directory entries with the new offsets, as well)?

Also, according to the documentation I have seen, the Value will be placed in the directory entry if it fits in the four bytes otherwise used by the Offset. Am I correct in assuming that the determination will be based on the value type (i.e. BYTE, SHORT, LONG will be stored in the directory entry, while (ASCII) strings and RATIONAL values are pointed to by the Offset? Did I miss any of the value types?