AWARE SYSTEMS
TIFF and LibTiff Mail List Archive

Thread

2002.09.05 09:56 "Decode group4", by Jan Edmundson
2002.09.05 10:21 "Re: Decode group4", by Frank D. Cringle
2002.09.05 11:56 "Re: Decode group4", by Scott Wagner
2002.09.05 16:34 "Re: Decode group4", by Lee Howard
2002.09.05 17:45 "Re: Decode group4", by Frank D. Cringle
2002.09.05 18:02 "Re: Decode group4", by Lee Howard
2002.09.09 12:27 "Re: Decode group4", by Jan Edmundson
2002.09.05 13:16 "Re: Decode group4", by Peter Nielsen

2002.09.05 11:56 "Re: Decode group4", by Scott Wagner

Jan et. al.,

My two cents - Frank Cringle's codec as implemented in LibTiff is extremely efficient and is well-tested. At this point the codec itself has acquired the mantle of being somewhat of a "reference standard" implementation of G3/G4/Huffman encoding. I think encapsulating it as a C++ class is a great idea, but if you do so (especially if you put it back in the public domain), it would be a good idea to leave the codec engine itself alone and just wrap encapsulation code around it. I have fiddled with this type of codec before - both my own implementations and those of others - and have learned that such implementations are often prone to bizarre and difficult-to-find bugs.

If you use "a C++ class implementation of Frank Cringle's codec," you will be incorporating a lot more than just a few lines of code - the years of testing this codec have gone through are of great value.

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