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

2006.04.04 02:19 "New OJPEG support", by Joris Van Damme
2006.04.04 03:28 "Re: New OJPEG support", by Bob Friesenhahn
2006.04.04 04:20 "Re: New OJPEG support", by Joris Van Damme

2006.04.04 02:19 "New OJPEG support", by Joris Van Damme

Folks,

The new tif_ojpeg.c has just been dropped into CVS. At your convinience,
please test, and be merciless.

Some important notes:

- While I've no clue about your *nix makefile trouble (oops... sorry,
disregard that last word), I understand that tif_ojpeg.c is optional and
not included by default. You'll have to do something special to include
it, and I hope you know 'cause I don't.

- The new tif_ojpeg.c does not require the old hack in LibJpeg. Don't
forget to remove that hack if you used the old tif_ojpeg.c before.

- The new tif_ojpeg.c does not support TIFFTAG_JPEGCOLORMODE. If your
own application level doesn't handle YCbCr and desubsampling, you may
test and use tif_ojpeg.c through the tif_getimage.c layer instead. This
tif_getimage.c does support YCbCr and desubsampling for planarconfig
contig, not separate, but almost all tif_ojpeg images are contig anyway.

- I've not been able to test the longjump way to call LibJpeg
functions... Some environments don't support longjump. This includes my
own LibTiffDelphi build. Thus, I've included an alternative way of
calling, triggered by the optional define LIBJPEG_ENCAP_EXTERNAL. If you
define that, LibJpeg doesn't get called directly, but you have a chance
to implement dedicated call encapsulators outside of tif_ojpeg.c. The
use with this LIBJPEG_ENCAP_EXTERNAL is tested, but the default, direct
longjump call usage without LIBJPEG_ENCAP_EXTERNAL is not. I must depend
on you to do that and report any problems. Default is normal longjump,
so you likely don't need to change anything.

- Please make a note of any compiler warnings you see. Even if they
don't impact functionality, I'm eager to learn about them and solve
them.

- Please test with all OJPEG files you have, even if you've already
posted me your testfiles... I've build support for all testfiles I've
received, but, still, there are different ways to use the library, and
maybe I've missed one in my testing process...

- Any remark, small, big, or huge, please tell me... I aim to please.



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