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January 1997
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1997.01.15 17:32 "Re: Problem with CCITT G4 and long scanlines", by Mogens Sorensen
Thanks for your suggestion, I have just implemented it and it seems to work out fine, it does however need further testing over the next days. The change only involves 10-12 lines of code, all connected to the internally allocated run array. Anybody wants the changed code ? drop me a line. At 16:51 +0100 14/01/97, Frank D. Cringle wrote: >Mogens Sorensen <ms@pe.dk> writes: >>I am using v3.4beta35 on WinNT and have run into some problems with Group 4 >>compression when the scanline width exceeds 65536 pixels (16 bits ?). > >Decompression, for G3 and G4, is handled by tif_fax3.[h,c]. There is >a built in assumption that uint16 is sufficient to hold a run-length. >So decompression certainly won't work with >65535 pixel lines. If you >change most occurrences of uint16 to uint32 in those 2 files it might >work. Most? Well, all except the one in typedef struct TIFFFaxTabEnt >in tif_fax3.h, I guess. This is from a very brief eyeballing of the >code. I haven't tried it and I don't have time to get involved. >Sorry. > ------------------------------------------------------------------ ! PURUP ESKOFOT A/S ! Phone........: +45 8743 4343 ! ! Mogens Sorensen, R&D ! Phone direct.: +45 8743 4372 ! ! Sonderskovvej 5 ! Fax..........: +45 8743 4445 ! ! DK-8520 Lystrup, DENMARK ! E-mail.......: ms@pe.dk ! ------------------------------------------------------------------