Is it possible to add padding within a figure?

In my document, I have this code:

begin{figure}[h]
  centering
  Ovalbox{includegraphics[width=0.75textwidth]{sym_transistors}}
  caption{}
  label{sym:transistors}
end{figure}

It yields this output:

As you can see in the bottom right corner, the Ovalbox is very tight. The simple solution for this is to open the eps-file in Inkscape and add an invisible rectangle – bigger than the graphics – behind all the symbols and recompile the document.

But, instead of doing that, is it possible to increase the padding within the Ovalbox/figure so I don’t have to edit the image? For example, CSS has the possibility to add "padding: 5px;" to an element, which will add a 5 pixel margin on all sides of the element. Is something similiar possible to do in LaTeX?