AWARE [SYSTEMS] Imaging expertise for the Delphi developer
AWare Systems, Imaging expertise for the Delphi developer, Home TIFF and LibTiff Mailing List Archive

LibTiff Mailing List

TIFF and LibTiff Mailing List Archive
April 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



Valid HTML 4.01!



Thread

2006.04.14 14:59 "TIFFReadScanline with JPEG compression", by Jason Summers
2006.04.14 16:48 "Re: TIFFReadScanline with JPEG compression", by Joris Van Damme
2006.04.17 20:47 "Re: TIFFReadScanline with JPEG compression", by Jason Summers
2006.04.17 22:25 "Re: TIFFReadScanline with JPEG compression", by Joris Van Damme

2006.04.14 16:48 "Re: TIFFReadScanline with JPEG compression", by Joris Van Damme

Jason,

Jason Summers wrote:
> I'm having trouble getting libtiff's TIFFReadScanline function to
> work with:
>
> (1) grayscale old-JPEG images. Some scanlines succeed, but others fail
> with a "LibJpeg: Improper call to JPEG library in state 0" error. This
> is with the latest libtiff from CVS. It works fine if I use
> TIFFReadEncodedStrip.
>
> (2) color new-JPEG images when using JPEGCOLORMODE_RGB. This used to
> work for me, but it has stopped working in recent versions of libtiff,
> at least for some images such as the quad-jpeg.tif sample. Using
> TIFFReadEncodedStrip (without JPEGCOLORMODE_RGB) works fine.
>
> I know I may not be giving enough details. But is TIFFReadScanline
> even *supposed* to work in these cases, or should I just give up and
> always use the memory-hungry TIFFReadEncodedStrip?

If your need is urgent, I recommend using strip access without
JPEGCOLORMODE_RGB. That part was recently serviced, and should work fine
(as you seem to indicate). For other approaches, please feel free to
file a bug report in BugZilla, and post a follow-up with the exact URL
of the BugZilla entry here. I'll try and deal with it as soon as I can.


Best regards,

Joris Van Damme
info@awaresystems.be
http://www.awaresystems.be/
Download your free TIFF tag viewer for windows here:
http://www.awaresystems.be/imaging/tiff/astifftagviewer.html