Nautilus leaks memory when thumbnailing jpeg2000 images

[Federico <federicotg gmail com>]

I noticed nautilus was using 1GB of RAM and I had to call nautilus -q to return my system to a stable situation.
Apparently valgrind confirms my hypothesis that jpeg2000 thumbnailing is leaking ~15 MB per image (lossless 24 bit 2200 by 2600 pixels). More or less the images' uncompressed size is leaked.

I'm running nautilus 3.6.3 and libgdk-pixbuf 2.28.0. Maybe not the latest versions.

I created the images from TIFF using imagemagick's mogrify.

Full valgrind output of 15 jp2 files thumbnailed here:
https://bugs.launchpad.net/ubuntu/+source/nautilus/+bug/1225201

Valgrind output segment of 3 jp2 thumbnailed images

==7309== 52,299,264 bytes in 3 blocks are possibly lost in loss record 13,216 of 13,216
==7309==    at 0x4C2CD7B: malloc (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
==7309==    by 0x72AC150: gdk_pixbuf_new (in /usr/lib/x86_64-linux-gnu/libgdk_pixbuf-2.0.so.0.2800.0)
==7309==    by 0x142012CE: jasper_image_stop_load (in /usr/lib/x86_64-linux-gnu/gdk-pixbuf-2.0/2.10.0/loaders/libpixbufloader-jasper.so)
==7309==    by 0x72B2CA9: gdk_pixbuf_loader_close (in /usr/lib/x86_64-linux-gnu/libgdk_pixbuf-2.0.so.0.2800.0)
==7309==    by 0x5471919: ??? (in /usr/lib/libgnome-desktop-3.so.4.0.0)
==7309==    by 0x5471E51: gnome_desktop_thumbnail_factory_generate_thumbnail (in /usr/lib/libgnome-desktop-3.so.4.0.0)
==7309==    by 0x4D8B2A: thumbnail_thread_start (nautilus-thumbnails.c:546)
==7309==    by 0x8A70F8D: start_thread (pthread_create.c:311)
==7309==    by 0x8D7FE1C: clone (clone.S:113)