[gdk-pixbuf] lib: Add note about min timeout in GIF being 20 msecs

[Bastien Nocera <hadess src gnome org>]

commit fcefaba236daa078be81e12c3270c4d1fda6c633
Author: Bastien Nocera <hadess hadess net>
Date:   Wed Oct 22 18:31:54 2014 +0200

    lib: Add note about min timeout in GIF being 20 msecs
    
    https://bugzilla.gnome.org/show_bug.cgi?id=544884

 gdk-pixbuf/gdk-pixbuf-animation.c |    4 ++++
 1 files changed, 4 insertions(+), 0 deletions(-)
---
diff --git a/gdk-pixbuf/gdk-pixbuf-animation.c b/gdk-pixbuf/gdk-pixbuf-animation.c
index a684b87..4d07653 100644
--- a/gdk-pixbuf/gdk-pixbuf-animation.c
+++ b/gdk-pixbuf/gdk-pixbuf-animation.c
@@ -723,6 +723,10 @@ gdk_pixbuf_animation_iter_init (GdkPixbufAnimationIter *iter)
  * conveniently takes a timeout in milliseconds, so you can use a timeout
  * to schedule the next update.
  *
+ * Note that some formats, like GIF, might clamp the timeout values in the
+ * image file to avoid updates that are just too quick. The minimum timeout
+ * for GIF images is currently 20 milliseconds.
+ *
  * Return value: delay time in milliseconds (thousandths of a second)
  **/
 int