2005.03.08 00:11 "Re: [Tiff] G4 1D/2D Decompression - Can't understand the Code :-(", by Joris Van Damme

Cromwell,

i've just read your [Tiff] Using TIFFGetField to get a "Rational" <http://xserve.flids.com/pipermail/tiff/2004-November/000824.html> contribution to the "Tiff" mailing list, for which i didn't notice a reply.

Perhaps you should consult the archive over at http://www.awaresystems.be/imaging/tiff/tml.html, as it has better threading. Allthough that particular thread spinned out-of-topic, definite answers were given. See:

http://www.asmail.be/msg0054698123.html
http://www.asmail.be/msg0054669769.html

I notice your pointer to the pipermail archive message doesn't quite match your subject line or message content. Perhaps you were referring to the next message in line, in then archive, that one is a better match. It is the equivalent of http://www.asmail.be/msg0054704587.html in the archive with correct threading.

But the problem presented in that latter post is quite the opposite of what you're after, if I understand your intentions correctly. It was Michael's intention to use an existing LibTiff codec to work on raw data without the TIFF format wrapper. As I understand your message, it is your intention instead to use an existing independent code to work inside LibTiff, on data with the TIFF format wrapper. There is not much information about this available on-line. You should try examining the units tif_codec.c, as this is the place to add registration of your codec. You'll notice a reference there to the function TIFFInitDumpMode, this is the function that fully completes registration of the simplest codec in the package, the 'uncompressed' codec. This function is specificied in tif_dumpmode.c, the unit for this particular 'uncompressed' codec, that deserves your close attention. Put breakpoints in the particular functions there, to see when they are being called. It may also pay off to try feeding stuff you see there, like 'tif_decoderow' for example, in the archive search function over at http://www.awaresystems.be/imaging/tiff/tml.html.

Joris Van Damme
info@awaresystems.be
http://www.awaresystems.be/
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