autostack thumbnails

Hi,

I am looking for a bridge script which would autostack thumbnails (not the real files) by two (or three, or four, etc ...) for all the picture files inside a folder.

ex:

-selecting the 2 first thumbnails (the same picture but with different names), then stacking these 2 first thumbnails

-selecting the 2 next thumbnails and stacking these 2 thumbnails

- and so on ...

PS : don't know if it's important but I work with tiff files on PC

Thanks in advance to the Scripters community.