SWF files and GIF files

I am trying to replace the banner ad below which came with a theme

<img src=”https://—-/hosting/hg468.gif&#8221; />

with something from my wp-content/uploads folder, full syntax below but I can’t get it to work.

https://www.lookupyoursite.com/wp-content/uploads/2012/12/blackstar.swf

I notice there are two file types involved, .gifs and .swf.

Will appreciate some guidance on how to make it work. I can make simple flash banners so I think it is time for me to start exploring the world of gif files.

I will appreciate suggestions on how to change the html code.

Thanks.