[l2h] png images

[Thomas Sams]

I had the same problem with shadows on formulae. Some kind l2h user advised 
me how to fix it. However, the fix was quite complicated, and involved 
reinstalling pnmcrop and the package it comes in. So I found it easier to 
do (tcsh under unix):  

cd directory
foreach i (*.png)
  pngtopnm $i | pnmcrop -black | pnmtopng - > $i
end
cd ..

or an equivalent script. You could write a perl script that would be 
more portable than the above. 

Thomas Sams