[barcode] PNG output backend

[David Santinoli]

Hallo,
  I've implemented an output back-end for the PNG image format.  It
currently relies on libgd, which I admit might sound like bloat, but
could be rewritten to depend only on libpng and freetype.  (On the other
hand, thanks to libgd a wealth of other bitmapped output formats could
be added with very little extra effort.)

Could such an addition be considered for inclusion in barcode?  In this
case, I can provide patches for both the library and the command-line
front-end.


By the way, is there any reason for bc->width being set in ean.c?
According to the documentation, if bc->width is unset it should be
computed by the output engine, not by encoders (ean.c is actually the
only one going this far).


(Please CC: me as I'm not on the list.)

Cheers,
 David
-- 
 David Santinoli, Milano             +   <david@santinoli.com>
 Independent Linux/Unix consultant   +   http://www.santinoli.com