imagemin-zopfli 
Zopfli imagemin plugin
Install
$ npm install --save imagemin-zopfli
Usage
const imagemin = require('imagemin');
const imageminZopfli = require('imagemin-zopfli');
imagemin(['images/*.png'], 'build/images', {
use: [
imageminZopfli({more: true})
]
}).then(() => {
console.log('Images optimized');
});
API
imageminZopfli([options])(buffer)
options
Type: Object
8bit
Type: boolean
Default: false
Convert 16-bit per channel image to 8-bit per channel.
transparent
Type: boolean
Default: false
Allow altering hidden colors of fully transparent pixels.
iterations
Type: integer
Default: 15
Number of iterations for images smaller than 200 KiB.
more
Type: boolean
Default: false
Compress more using more iterations (depending on file size).
buffer
Type: Buffer
Buffer to optimize.
License
MIT © imagemin