Converting from file with base64 string to png image.
4 variants which works.
var {promisify} = require('util');
var fs = require("fs");
var readFile = promisify(fs.readFile)
var writeFile = promisify(fs.writeFile)
async function run () {
// variant 1
var d = await readFile('./1.txt', 'utf8')
await writeFile("./1.png", d, 'base64')
// variant 2
var d = await readFile('./2.txt', 'utf8')
var dd = new Buffer(d, 'base64')
await writeFile("./2.png", dd)
// variant 3
var d = await readFile('./3.txt')
await writeFile("./3.png", d.toString('utf8'), 'base64')
// variant 4
var d = await readFile('./4.txt')
var dd = new Buffer(d.toString('utf8'), 'base64')
await writeFile("./4.png", dd)
}
run();