[magick-users] Tile cropping with overlap ?

[magickusers.domain.thewild at spamgourmet.org]

Hi list !

I am trying to accomplish a quite simple task with imagemagick : cropping an 
image into tiles of a given dimension *with overlap* between the tiles.
Cropping is easy : convert myimage.jpg -crop <sizex>x<sizey> myoutpout%d.jpg
But I can't find a way to tell convert that I want the tiles to overlap by a 
certain amount (in pixels).
convert myimage.jpg -crop <sizex>x<sizey>+<offsetx>+<offsety> myoutpout%d.jpg
does not work, it just produces the first tile with an offset (i.e., it is the 
same with or without the "%d").

Is this possible with convert ?

Thanks a lot !

--
Arnaud