I've got this code:

#+begin_src latex :packages '(("" "tikz")) :exports results :results output raw :file fsa.png
\usetikzlibrary{backgrounds}
\begin{tikzpicture}
  \draw (0,0) grid (10,5);
  \draw (0,0) node[below left] {$A$};
  \draw (10,5) node[above right] {$B$};
  \fill (0,0) circle (2pt);
  \fill (10,5) circle (2pt);
\end{tikzpicture}
#+end_src

#+begin_src latex :packages '(("" "qtree")) :exports results :results output raw :file tree1.png
 \Tree [.sum [.squares [.prime-numbers initial seven ] ] ]
#+end_src

running in an org file, and it gives me embedded images in an html file. (See this). But they're cramped and have a strange gray background. How can I not clip and get the png transparent working?

LB