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May 1997
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1997.05.23 19:56 "Re: CCITT Grp 4 - uncompressed data", by Frank D Cringle
pelcak@xyvision.com writes: >"Fax4Decode: ... Uncompressed data (not supported) ... ". >Inspection of the source code in tif_fax3.c showed that: > >1. The encode/decode algorithm has been completely >re-done, to one "derived from Frank Cringle's viewfax"; > >2. The current code most certainly does not support >the uncompressed data option for CCITT Group 4. > >Why is this option no longer supported? Because I was too lazy to include it in my code. I guess Sam thought the advantages of the new code for the normal (compressed) case outweighed this omission. Also, uncompressed T.6 mode is somewhat deprecated by the TIFF Spec (p.53): Uncompressed mode is not well-specified and many applications discourage its usage, prefering alternatives such as different compressions on a segment-by-segment (strip or tile) basis, or by simply leaving the image uncompressed... That is not much consolation if you have such images to deal with, though. >Is there anything that we can do so that we can handle >CCITT Group 4 graphics using that option? Use an old libtiff version or add the functionality to the current version. -- Frank Cringle, fdc@cliwe.ping.de voice: (+49 2304) 467101; fax: 943357