There is a program for zaurus which is able to zoom and
combined views of overlapping images. Do you mind to ask
them for the solution of this? It works pretty good on
But it seems not to be further developed since 2002.
" Localizer is not yet GPL. I'll publish the source
under the GPL license if there's enough interest. In other
case, it will remain freeware (free to distribute, copy and
use, but just the binary, docs and examples)."