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 2008

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

2008.04.16 13:26 "efficient thumbnailing", by Dr Michael J Chudobiak
2008.04.16 14:55 "Re: efficient thumbnailing", by Seth Price
2008.04.16 16:05 "Re: efficient thumbnailing", by Phillip Crews
2008.04.16 19:01 "Re: efficient thumbnailing", by Dr Michael J Chudobiak
2008.04.16 15:19 "Re: efficient thumbnailing", by <jcupitt@gmail.com>
2008.04.16 16:52 "Re: efficient thumbnailing", by Kai-uwe Behrmann
2008.04.16 17:29 "Re: efficient thumbnailing", by Dr Michael J Chudobiak
2008.04.16 19:37 "Re: efficient thumbnailing", by Kai-uwe Behrmann
2008.04.17 12:08 "Re: efficient thumbnailing", by Dr Michael J Chudobiak
2008.04.17 06:02 "Re: efficient thumbnailing", by Joris Van Damme
2008.04.17 11:57 "Re: efficient thumbnailing", by Dr Michael J Chudobiak
2008.04.17 13:48 "Re: efficient thumbnailing", by Joris Van Damme

2008.04.16 13:26 "efficient thumbnailing", by Dr Michael J Chudobiak

Hi all,

Is there an efficient way to generate thumbnails from tiff files?

Currently, when the gnome/gtk+ gdk-pixbuf tiff loader wants to generate 
a thumbnail of a tiff file, it loads the entire image, and then scales 
it. (See 
http://svn.gnome.org/viewvc/gtk%2B/trunk/gdk-pixbuf/io-tiff.c?view=markup).

This uses a lot of memory, and the gtk+ scale-down routines are not very 
good (http://bugzilla.gnome.org/show_bug.cgi?id=80925).

Is there a way in libtiff to do some scale-while-loading, or prescaling, 
to reduce memory usage and speed things up? (Or could it be added to 
libtiff?)

The jpeg loader uses some fast-scaling trickery to scale down by a 
factor of 2, 4, or 8 first (http://sylvana.net/jpegcrop/djpeg) - I was 
wondering if there is a tiff equivalent.

Suggestions and pointers to existing code appreciated!

- Mike