Question on pics in sig line

Your signature line may not exceed 400 characters. This
400-character limit includes all characters, including spaces
and URLs for links and images. You may have no more than one
image (.jpg or .gif format) in your signature line at any
time. This image may not exceed 500 pixels wide, 200 pixels
tall, or a file size of 20 kilobytes. If you do not know if
your image is in compliance, right click on it and select
"Properties." You may not use any HTML code in your
signature line except the special message board code for:
bold, italics, links, center, and line breaks. You are limited
to a maximum of two line break [br] tags.

http://www.democraticunderground.com/forums/rules_detailed.html