Make picture background transparent

index.js

const { promisify } = require('util')
const { resolve } = require('path')
const fs = require('fs')
const readdir = promisify(fs.readdir)
const stat = promisify(fs.stat)
const sharp = require("sharp")
const replaceColor = require('replace-color')

async function process(path) {
	if (path.includes("cards-raw")) {
		path = path.split("cards-raw").pop()
	}

	const prodFolder = "./cards-correct"
	const rawFolder = "./cards-raw"

	try {
		const picture = await sharp(`${rawFolder}/main.png`).withMetadata().toBuffer()

		const SIZE = 400
		const width = SIZE
		const height = SIZE
		const channels = 4
		const rgbaPixel = 0x00000000

		const canvas = Buffer.alloc(width * height * channels, rgbaPixel)
	
		let processedPicture = await sharp(canvas, { create: { width: SIZE, height: SIZE, channels: 3, background: "#252525" }})
			.composite([{ input: picture, gravity: "center" }])
			.withMetadata()
			.png()
			.toBuffer()

		processedPicture = await new Promise(resolve => {
			replaceColor({
				image: processedPicture,
				colors: {
					type: "hex",
					targetColor: "#252525",
					replaceColor: "#ff00e5"
				}
			}, (error, jimpObject) => {
				jimpObject.write(`${prodFolder}${path}`, (async callback => {
					const pic = await sharp(`${prodFolder}${path}`).withMetadata().toBuffer()

					resolve(pic)
				}))
			})
		})

		processedPicture = await sharp(processedPicture)
			.trim()
			.toBuffer()
		
		await new Promise(resolve => {
			replaceColor({
				image: processedPicture,
				colors: {
					type: "rgb",
					targetColor: [255, 0, 229],
					replaceColor: [255, 0, 229, 0]
				},
				deltaE: 10
			}, (error, jimpObject) => {
				jimpObject.write(`${prodFolder}${path}`, resolve)
			})
		})
	} catch(error) {
		console.error(error)
	}
}

async function getFiles(dir) {
  const subdirs = await readdir(dir)
  const files = await Promise.all(subdirs.map(async (subdir) => {
    const res = resolve(dir, subdir)
    return (await stat(res)).isDirectory() ? getFiles(res) : res
  }))
  return files.reduce((a, f) => a.concat(f), [])
}

async function start() {
	let files = await getFiles("./cards-raw")

	files = files.map(file => {
		return `./cards-raw${file.split("cards-raw").pop()}`
	})

	await Promise.all(
		files.map(file => process(file))
	)

	console.log("ACABOU!")
}

start()