Controlling the size of org babel image outputs in latex

[Ellis Adigvom]

Hi,

I have an org mode document with some embedded PlantUML code blocks. I 
export this file to PDF through latex (C-c C-e l p). I have some 
diagrams which are rather small, but they are expanded to fill the page, 
and this looks awkward in the result.

How can I control the size of the image in the exported file? I've tried 
using:

    #+ATTR_LATEX: :width: 4cm
    #+BEGIN_SRC plantuml :file diagram.png

    ...

    #+END_SRC

But this doesn't have any impact on the output. Can anyone help me with 
this?