On Sun, Aug 30, 2009 at 9:51 AM, <jcup...@gmail.com> wrote: > 2009/8/28 Mark <mark...@gmail.com>: >> static GdkPixbuf * >> scale_pixbuf_preserve_aspect_ratio (GdkPixbuf *pixbuf, >> gint size, >> GdkInterpType interp) > > One more idea: this will be very slow for JPEGs (your use case, I think). > > It will decode the whole file, then shrink. libjpeg supports > shrink-on-load where it only decompresses enough of the file to be > able to supply pixels at a certain size. In particular, libjpeg can do > a very quick load-at-1/8th-size read where it just decompresses enough > to be able to get the DC component of each 8x8 block. If you use > libjpeg like this you can expect around a 100x speedup of the > decompress step. > > I have some code that does this lying around, I'll try to clean it up > and post it next week so you can test it. Or maybe glib does this > already? I know imagemagick uses this trick for it's thumbnailing (if > it didn't it'd be far slower than glib, heh).
glib has nothing to do with it. gdk-pixbuf supports loading jpegs at reduced size already. _______________________________________________ gtk-devel-list mailing list gtk-devel-list@gnome.org http://mail.gnome.org/mailman/listinfo/gtk-devel-list
