image-hide

Put a secret image into another image using alpha channel magic.

Try to view this image under black background:

Inspired by Hackergame 2019

Usage

npm install --save image-hide

import { promises as fs } from 'fs'
import hide from 'image-hide'

// Size (width & height) of these images should be same.
let imageA = await fs.readFile('a.png')
let imageB = await fs.readFile('b.png')

await fs.writeFile('result.png', Buffer.from(hide(imageA, imageB)))