http://office.microsoft.com/en-us/assistance/HA011266301033.aspx
This page will tell you how to compress. Try undoing whatever it tells you
to do. (I'll confess, I haven't tried this but common sense says it's a
place to start.)

Jazziz,

Please explain what you mean by automatic compressing?

Perhaps what you are experiencing is your background picture being converted
to a GIF image? You can't do everything in a web document that you can a
print document with Publisher. In a print document, you can overlap images,
text boxes and other page elements, but in a web page document, those
overlapping elements will be combined and converted to one large GIF, which
you might call 'visually unfeasable'.

To check this go to the folder where you publish the HTML, and look at the
images that were generated to see if your original image has been combined
with other elements and converted into a GIF. If this is what is happening,
then you will have to redesign your page so that you don't have overlapping
elements.

DavidF