# png

[![Build Status][travis-image]][travis-url]
[![NPM Version][npm-version-image]][npm-url]
[![NPM Downloads][npm-downloads-image]][npm-url]
[![MIT License][license-image]][license-url]
[![Standard Version][standard-version-image]][standard-version-url]
[![Codecov][codecov-image]][codecov-url]

> 🖼A full-featured PNG decoder and encoder. Fork of @vivaxy/png maintained as of Feb 2023.

# Supports

- Environments: Browsers and Node.js
- Chunks: IHDR, PLTE, IDAT, IEND, tRNS, cHRM, gAMA, iCCP, sBIT, sRGB, tEXt, zTXt, iTXt, bKGD, hIST, pHYs, sPLT, tIME
- Color Types: Greyscale, Truecolour, Indexed-colour (Palette), Greyscale with alpha, Truecolour with alpha
- Bit Depths: 1, 2, 4, 8, 16
- Filters: None, Sub, Up, Average, Paeth

# Install

`yarn add @stevebel/png` or `npm i @stevebel/png`

# Usage

```js
import * as png from '@stevebel/png';

const metadata = png.decode(imageBuffer);
const imageBuffer = png.encode(metadata);
```

See `metadata` type definition in [metadata.ts](src/helpers/metadata.ts).

# Articles

- [Decoding A PNG Image with JavaScript Step by Step](https://vivaxyblog.github.io/2019/11/07/decode-a-png-image-with-javascript.html) 中文版：[一步一步解码 PNG 图片](https://vivaxyblog.github.io/2019/12/07/decode-a-png-image-with-javascript-cn.html)

# Prior Art

- [PngSuite - the official set of PNG test images](http://www.schaik.com/pngsuite/)
- [upng-js](https://github.com/photopea/UPNG.js)
- [PNGjs-Image](https://github.com/YahooArchive/pngjs-image)
- [fast-png](https://github.com/image-js/fast-png)
- [pngparse-sync](https://github.com/mikolalysenko/pngparse-sync)
- [pngjs3](https://github.com/gforge/pngjs3)
- [pngjs](https://github.com/lukeapage/pngjs)
- [png-js](https://github.com/foliojs/png.js)

#

_Project created by [create-n](https://github.com/vivaxy/create-n)._

[travis-image]: https://img.shields.io/travis/stevebel/png.svg?style=flat-square
[travis-url]: https://travis-ci.org/stevebel/png
[npm-version-image]: https://img.shields.io/npm/v/@stevebel/png.svg?style=flat-square
[npm-url]: https://www.npmjs.com/package/@stevebel/png
[npm-downloads-image]: https://img.shields.io/npm/dt/@stevebel/png.svg?style=flat-square
[license-image]: https://img.shields.io/npm/l/@stevebel/png.svg?style=flat-square
[license-url]: LICENSE
[standard-version-image]: https://img.shields.io/badge/release-standard%20version-brightgreen.svg?style=flat-square
[standard-version-url]: https://github.com/conventional-changelog/standard-version
[codecov-image]: https://img.shields.io/codecov/c/github/stevebel/png.svg?style=flat-square
[codecov-url]: https://codecov.io/gh/stevebel/png