Any way to limit the ICONS resource?

["Christopher P. Lindsey" <lindsey@xxxxxxxxxxx>]

Is there any way to limit the ICONS resource to only
be displayed if images are of a certain size?  

Right now I have

<ICONS>
   image/*;[16x14]/images/blackcamera.gif
   multipart/mixed;[16x14]/images/blackcamera.gif
   multipart/related;[16x14]/images/blackcamera.gif
   application/octet-stream;[16x14]/images/blackcamera.gif
</ICONS>

to display a little camera icon in the Subject: header of my
threaded message listing if there is an image in the message.

However, I'm now finding that people have little Facebook, Google,
or other icons in their signature files that I don't want to
match on.  Ideally, I'd just ignore any image that isn't 100x100
(or some other arbitrary measurement) when using the ICONS
resource.

Is the best way to add a new resource (like ICONRESTRICT)
that can be expanded to include other restrictions, then
modify the ICONS code to check these conditions?  Or is
there something simpler that I could do?

Chris