advpng-bin 
The main purpose of this utility is to recompress png files to get the smallest possible size
Install
$ npm install --save advpng-bin
Usage
var execFile = require('child_process').execFile;
var advpng = require('advpng-bin');
execFile(advpng, ['--recompress', '--shrink-extra', 'image.png'], function (err) {
console.log('Image minified!');
});
CLI
$ npm install --global advpng-bin
$ advpng --help
License
MIT © imagemin