Using the following link to insert banner to the sharepoint site
http://www.thesharepointintern.com/2012/08/add-banner-to-your-sharepoint-site_30.html
However do I have to edit the master page of each site ie v4.master. I have one site collection but have unique sites, and each site has a v4.master page. Do I have to edit each v4.master pages for each unique site?