#PNGLib A PNG lib for Node.js
A handy class to calculate color values.
version 1.0
author Robert Eisele <robert@xarg.org>
copyright Copyright (c) 2010, Robert Eisele
link http://www.xarg.org/2010/03/generate-client-side-png-files-using-javascript/
license http://www.opensource.org/licenses/bsd-license.php BSD License
Modified by George Chan gchan@21cn.com
##Install
npm install pnglib
##Examples
var pnglib = require('pnglib');
var p = new pnglib(300,100,8);
var lineIndex = p.index(10,25);
p.buffer[lineIndex+j]='\x01';
p.color(0, 0, 0, 0); // First color: background (red, green, blue, alpha)
p.color(80, 80, 80, 255); // Second color: paint (red, green, blue, alpha)
More example see: https://github.com/GeorgeChan/captchapng