ndarray-pixels

ndarray-pixels

WORK IN PROGRESS: Experimental.

Convert ndarray ↔ image data, on Web and Node.js.

Designed to be used with other ndarray-based packages.

In Node.js, this package uses get-pixels and save-pixels. While both packages could be used on the web, they require polyfills for Node.js builtins. Browserify handles that automatically, but more modern bundlers do not. Moreover, the polyfills increase package size significantly. To avoid these problems, web builds of ndarray-pixels reimplement the same functionality with the more portable Canvas API.

Supported Formats

Platform	JPEG	PNG	Other
Node.js	✅	✅	❌
Web	✅	✅	Based on browser support

Quickstart

npm install --save ndarray-pixels

Web

import { getPixels, savePixels } from 'ndarray-pixels';

const bytesIn = await fetch('./input.png')
    .then((res) => res.arrayBuffer())
    .then((arrayBuffer) => new Uint8Array(arrayBuffer));

const pixels = await getPixels(bytesIn, 'image/png'); // Uint8Array -> ndarray

// ... modify ndarray ...

const bytesOut = await savePixels(pixels, 'image/png'); // ndarray -> Uint8Array

Node.js

const fs = require('fs');
const { getPixels, savePixels } = require('ndarray-pixels');

const bufferIn = fs.readFileSync('./input.png');
const pixels = await getPixels(bufferIn, 'image/png'); // Uint8Array -> ndarray

// ... modify ndarray ...

const bufferOut = await savePixels(pixels, 'image/png'); // ndarray -> Uint8Array
fs.writeFileSync('./output.png', bufferOut);

To Do

• The Node.js implementation seems to break when given an Uint8Array instead of a Buffer; see test suite.