@ismay/ndarray-pixelsort v0.1.0

ndarray-pixelsort

pixelsort images

Based on the algorithm popularised by Kim Asendorf. It sorts the pixels in an image by moving from the upper left to the bottom right pixel in a horizontal fashion, and checking for each pixel whether it matches a filter condition. If it does, it and all the following pixels that match the filter will be sorted according to a sorting algorithm. To sort in a different direction, rotate or flip the image accordingly before sorting.

Installation

$ npm install @ismay/ndarray-pixelsort

Example

So for example:

const util = require('util');
const getPixels = util.promisify(require('get-pixels'));
const savePixels = require('save-pixels');
const fs = require('fs');
const streamToPromise = require('stream-to-promise');
const pixelsort = require('@ismay/ndarray-pixelsort');

/**
 * The filter function should accept red, green and blue values (from 0 - 255), and return a boolean
 * that is used to decide whether to filter or not
 */

const filter = (red, green, blue) => red > 0 && green > 0 && blue > 0;

/**
 * The sort function is used to sort an array of colors, where the colors are arrays of red, green
 * and blue values (from 0 - 255). The sorting is done with the native `sort` array method
 */

const sort = (a, b) => (a[0] + a[1] + a[2]) - (b[0] + b[1] + b[2]);

getPixels('./image.png')
  .then(image => {
    const sorted = pixelsort(image, filter, sort);
    return streamToPromise(savePixels(sorted, 'png'));
  })
  .then(sortedImage => {
    fs.writeFileSync('./sorted.png', sortedImage);
  });
});

API

pixelsort(image, filter, sort) ⇒ ndarray

Pixelsort images

Kind: global function Returns: ndarray - The pixelsorted ndarray

License

MIT