[KPhotoAlbum] Crash from the latest svn

[Robert Krawitz]

   From: "Jesper K. Pedersen" <jesper.pedersen at kdab.com>
   Date: Tue, 17 Aug 2010 13:05:49 +0200

   On Tuesday 17 August 2010 02:01:42 Robert Krawitz wrote:
   | The latest svn crashed when I attempted to resize the thumbnail grid
   | with the mouse middle button.
   Hmm the traceback doesn't really indicate much to me, let me know if you can 
   reproduce this consistently.

I simply clicked on one of the corners inside the grid and dragged
"southeast".

   | (Personally, I think that that should be disabled with the new
   | thumbnail code -- accidentally changing the thumbnail size is
   | presumably a much more expensive operation now.

   Actually, the next thing I'll be working on is to try and make
   background threads generate thumbnails, so it shouldn't be that
   bad. But indeed something to consider.

If you have 100,000 photos and every one of them has to be
re-thumbnailed?  Even if it's done incrementally, at least until the
thumbnails are recreated they're going to have to get built on the
fly, which is very slow.

   | I also vaguely recall that we had a similar performance issue in the
   | KDE3 version that was resolved, at least partially, by using a quick
   | and dirty resampling algorithm rather than rescaling.  This made the
   | thumbnails less attractive but much faster to load.)

   Well actually, that was one of the things I threw out (see my
   blog), it took quite some time to do this scaling.

Even a fast resampling (not rescaling)?