LibTiff Mailing List
TIFF and LibTiff Mailing List Archive
December 2006
Previous Thread
Next Thread
Previous by Thread
Next by Thread
Previous by Date
Next by Date
Contact
The TIFF Mailing List Homepage
This list is run by Frank Warmerdam
Archive maintained by AWare Systems
Thread
2006.12.20 13:24 "Interpreting values in tdir_offset of TIFFDirEntry", by <mikk@go2.pl>
Hello, I'm not sure I understand the way of interpreting values stored in the tdir_offset of TIFFDirEntry structure. According to the tiff.h comments for the TIFFDirEntry struct: "...If the value is 4 bytes or less, then it is placed in the offset field to save space. If the value is less than 4 bytes, it is left-justified in the offset field." When the IFD entry (a tag) is written into a TIFF file, and the data type size is 2 bytes (fe. TIFF_SHORT), and data length is 2, that makes 4 bytes of data. I assume that the data itself is saved in the tdir_offset field. And what if the data type size is 1 byte (fe. TIFF_ASCII or TIFF_BYTE) and data length is less than or equal to 4? I assume that the data itself is saved in the tdir_offset. Am I right? Thanks in advance, mikk