imagemin-optipng 
Imagemin plugin for OptiPNG
Install
$ npm install imagemin-optipng
Usage
const imagemin = require('imagemin');
const imageminOptipng = require('imagemin-optipng');
(async () => {
await imagemin(['images/*.png'], 'build/images', {
use: [
imageminOptipng()
]
});
console.log('Images optimized!');
})();
API
imageminOptipng(options?)(buffer)
Returns a Promise<Buffer>.
options
Type: object
optimizationLevel
Type: number
Default: 3
Select an optimization level between 0 and 7.
The optimization level 0 enables a set of optimization operations that require minimal effort. There will be no changes to image attributes like bit depth or color type, and no recompression of existing IDAT datastreams. The optimization level 1 enables a single IDAT compression trial. The trial chosen is what. OptiPNG thinks it’s probably the most effective. The optimization levels 2 and higher enable multiple IDAT compression trials; the higher the level, the more trials.
Level and trials:
- 1 trial
- 8 trials
- 16 trials
- 24 trials
- 48 trials
- 120 trials
- 240 trials
bitDepthReduction
Type: boolean
Default: true
Apply bit depth reduction.
colorTypeReduction
Type: boolean
Default: true
Apply color type reduction.
paletteReduction
Type: boolean
Default: true
Apply palette reduction.
interlaced
Type: boolean | undefined | null
Default: false
Enable Adam7 PNG interlacing on any images that are processed. Interlaced images look better when they're loaded partially, but usually interlace makes compression less efficient. Set to undefined or null to keep the same interlacing as the input image.
errorRecovery
Type: boolean
Default: true
A reasonable amount of effort will be spent to try to recover as much data as possible of a broken image, but the success cannot generally be guaranteed.
buffer
Type: Buffer
Buffer to optimize.
