pngquant is a command-line utility for converting 24/32-bit PNG images to paletted (8-bit) PNGs. The conversion reduces file sizes significantly (often as much as 70%) and preserves full alpha transparency.
$ npm install --save pngquant-bin
var execFile = require('child_process').execFile;
var pngquant = require('pngquant-bin').path;
execFile(pngquant, ['-o', 'output.png', 'input.png'], function (err) {
if (err) {
throw err;
}
console.log('Image minified!');
});
$ npm install --global pngquant-bin
$ pngquant --help
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