Another logo in a Subforum

Hello,

actually I have a logo for all forums in:

include/template/main.tpl

<div id="brd-head" class="gen-content">
    <!-- forum_skip -->
<img src="forum/img/logo.jpg" style="margin: 1em;">
    <!-- forum_title -->
    <!-- forum_desc -->
</div>

Is there a way to decide what logo is shown or not in a subforum?

Thank you for your help.

Greetings,
Meteolab