Video thumbnails need tweaking

[Dave B.]

I am curious if there is a registry setting that would
allow me to change the frame number that is used to
generate thumbnails for video files in the explorer. The
system uses the first frame of a video as the default
setting, however many videos have a padding of black
frames at the beginning and end which renders the
thumbnail useless.
..

 

[Bob]

This is exactly what I am trying to do, too. Does anyone
know how to do this? Or does anyone know that it cannot
be done in Windows?
Dave B, did you get any response from this post?