Nodejs ffmpeg "The input file path can not be empty" error, but files exist - node.js

Question

I'm trying to merge an audio file with a video file from the same source (Youtube)
In the following code I first read in the console parameters wirh commander then i define the videoOutput dir and download the highset res. video from youtube with node-ytdl-core. After that I download the audio for the video. and in the callback of the video.on("end", ....)
i call the function merge()
const path = require('path');
const fs = require('fs');
const readline = require("readline");
const ytdl = require('ytdl-core');
const { program } = require('commander');
const ffmpeg = require('ffmpeg');
program
.option("--url, --url <url>", "Youtube video url")
.option("--name, --name <name>", "Name of the video in hard drive")
program.parse(process.argv);
const options = program.opts();
let url = options.url;
let name = options.name;
let videoOutput = path.resolve(`./video${name}.mp4`);
let video = ytdl(url, {
quality: "highestvideo"
});
let starttime = 0;
video.pipe(fs.createWriteStream(videoOutput));
video.once('response', () => {
starttime = Date.now();
});
video.on('progress', (chunkLength, downloaded, total) => {
const percent = downloaded / total;
const downloadedMinutes = (Date.now() - starttime) / 1000 / 60;
const estimatedDownloadTime = (downloadedMinutes / percent) - downloadedMinutes;
readline.cursorTo(process.stdout, 0);
process.stdout.write(`${(percent * 100).toFixed(2)}% downloaded `);
process.stdout.write(`(${(downloaded / 1024 / 1024).toFixed(2)}MB of ${(total / 1024 / 1024).toFixed(2)}MB)\n`);
process.stdout.write(`running for: ${downloadedMinutes.toFixed(2)}minutes`);
process.stdout.write(`, estimated time left: ${estimatedDownloadTime.toFixed(2)}minutes `);
readline.moveCursor(process.stdout, 0, -1);
});
video.on('end', () => {
process.stdout.write('\n\n');
});
// repeat for audio
video = ytdl(url, {
quality: "highestaudio"
});
starttime = 0;
let audioOutput = path.resolve(`./audio${name}.mp3`);
video.pipe(fs.createWriteStream(audioOutput));
video.once('response', () => {
starttime = Date.now();
});
video.on('progress', (chunkLength, downloaded, total) => {
const percent = downloaded / total;
const downloadedMinutes = (Date.now() - starttime) / 1000 / 60;
const estimatedDownloadTime = (downloadedMinutes / percent) - downloadedMinutes;
readline.cursorTo(process.stdout, 0);
process.stdout.write(`${(percent * 100).toFixed(2)}% downloaded `);
process.stdout.write(`(${(downloaded / 1024 / 1024).toFixed(2)}MB of ${(total / 1024 / 1024).toFixed(2)}MB)\n`);
process.stdout.write(`running for: ${downloadedMinutes.toFixed(2)}minutes`);
process.stdout.write(`, estimated time left: ${estimatedDownloadTime.toFixed(2)}minutes `);
readline.moveCursor(process.stdout, 0, -1);
});
function merge(){
ffmpeg()
.input("./videotest.mp4") //your video file input path
.input("./audiotest.mp3") //your audio file input path
.output("./finished.mp4") //your output path
.outputOptions(['-map 0:v', '-map 1:a', '-c:v copy', '-shortest'])
.on('start', (command) => {
console.log('TCL: command -> command', command)
})
.on('error', (error) => console.log("errrrr",error))
.on('end',()=>console.log("Completed"))
.run()
}
video.on('end', () => {
process.stdout.write('\n\n');
merge();
});
But even though the files are there ffmpeg throws me this error:
I also tried this in the video-end callback, because maybe the audio is finished downloading before the video, still doesn't work. I've also tried to rename the outputDirs for the files and keep the old files and rerun the script so the files are 100% there. Still doesn't work.
I have also tried absolute paths ("C:/..." also with backslash "C:\...") but I still get the error message that the input file path can't be empty.
Appreciate any piece of advise or help!

Answer 1

Ok I have found a solution.
First i moved my code for downloading the audio into the video.on("end",... callback of the video download.
I changed from require("ffmpeg") to these 5 lines:
const ffmpeg = require('fluent-ffmpeg');
const ffmpegPath = require('#ffmpeg-installer/ffmpeg').path;
const ffprobePath = require('#ffprobe-installer/ffprobe').path;
ffmpeg.setFfmpegPath(ffmpegPath);
ffmpeg.setFfprobePath(ffprobePath);
make sure to run:
npm i fluent-ffmpeg
and
npm i #ffprobe-installer/ffprobe
and
npm i #ffmpeg-installer/ffmpeg
that's my solution!