Need to Call Random Images to external page

[doctoreast]

Hi,

  Can someone point me in the right direction for
the script to call a single random image THUMB into
an external php page. 

 Previously, with coppermine, I used an
include string in external pages to call a php script
which was in the gallery folder.  I'm sure it's been
asked before, but I can't find it.  I did find instruction
for tinyportal, but I'm just using plain old php, no cms.

doc