Image::Pngslimmer version 0.11
=============================

OVERVIEW

Image::Pngslimmer reduces the size of PNGs by removing non-critcal chunks.

Other tools, such as pngcrush (http://pmt.sourceforge.net/pngcrush/) 
will deliver (much) better results for static PNGs and Image::Pnglimmer 
is specifically designed for dynamically created PNGs.

use Image::Pngslimmer

Image::Pngslimmer::ispng($blob) - returns 1 if the BLOB conforms to the
structure for a PNG and that all CRCs are correct.

Image::Pngslimmer::discard_noncritical($blob) - returns a BLOB stripped of any
non-critcal chunks. If the passed-in BLOB does not conform to the basic structure
of a PNG the returned BLOB is identical to the passed-in BLOB. The passed in BLOB
is not altered by this function.

Image::Pngslimmer::analyze($blob) - after calling Image::Pngslimmer::ispng($blob)
this will iterate through the chunks in the supplied byte stream represented by 
$blob and return an array of strings describing the chunks in the PNG. It can be
useful for testing the "before and after" effect of discard_noncritical($blob).

Image::Pngzlimmer::zlibshrink($blob) will attempt to improve compression of the supplied BLOB

Image::Pngslimmer::filter($blob) will attempt to apply adaptive filtering for
better compression of the supplied BLOB


INSTALLATION

To install this module type the following:

   perl Makefile.PL
   make
   make test
   make install

DEPENDENCIES


String::CRC32
Compress:Zlib
  

COPYRIGHT AND LICENCE


Copyright (C) 2006, 2007 by Adrian McMenamin <adrian AT newgolddream DOT info>

This library is free software; you can redistribute it and/or modify
it under the same terms as Perl itself, either Perl version 5.8.4 or,
at your option, any later version of Perl 5 you may have available.


