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. 1 trial
2. 8 trials
3. 16 trials
4. 24 trials
5. 48 trials
6. 120 trials
7. 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.