Duplicates images in the source subfolder to the root.

image_test_generator.js

/**
 * How to use?
 *
 * - Install Node.JS
 * - Install NPM
 * - Via terminal from here:
 * -- Browse to the Pictures folder
 * -- Save this script in a file called `index.js` (1st execution only)
 * -- Execute `npm i` (1st execution only)
 * -- Execute `node ./index.js`
 */

const fs = require("fs-extra");

const sourceFolder = `Camera Roll`; // SUBFOLDER WHO CONTAINS THE SOURCE IMAGES
const numImages = 20000; // HOW MANY IMAGES IT MUST TO ARCHIEVE

const images = fs.readdirSync(".").filter(e => {
  return (
    !fs.lstatSync(e).isDirectory() &&
    e != "index.js" &&
    e != "package.json" &&
    e != "package-lock.json"
  );
});

images.forEach(element => {
  console.log(`removing ${element}...`);
  fs.unlinkSync(element);
});

const name = new Date().valueOf().toString(32);
const sourceImages = fs.readdirSync(sourceFolder).filter(e => {
  return (
    !fs.lstatSync(`${sourceFolder}/${e}`).isDirectory() &&
    e != "index.js" &&
    e != "package.json" &&
    e != "package-lock.json"
  );
});

for (let i = 0; i < numImages; i++) {
  const sourceImage = sourceImages[i % sourceImages.length];

  console.log(`copying ${i}: ${sourceImage}...`);
  fs.copyFileSync(
    `./${sourceFolder}/${sourceImage}`,
    `./${i}_${name}${sourceImage.substr(sourceImage.lastIndexOf("."))}`
  );
}