Can i specify a rectangle within an image tag in a svg file

Hi All,

I was wondering whether we can specify a rectangle inside an image tag in a
svg file.

The thought came to my mind because, we know that when we specify an image,
it creates a new viewport, so i was wondering whether it is possible/legal
to render any other basic shape within that image viewport.

May be you can take a look at the attached svg file.My question is "the way
i have specified *rectangle with is rect1 *, it is a valid svg file or not.

Thanks & Regs.
Mustaf