How to run FFmpeg using NodeJS

Setting up

This tutorial assumes you already have NodeJS installed

Use the following to set up a new folder and package.json file

mkdir ffmpeg-tutorialcd ffmpeg ffmpeg-tutorialnpm init # enter ffmpeg-tutorial as the name and then skip through the rest

You should now have package.json which looks like the following:

{  "name": "ffmpeg-tutorial",  "version": "1.0.0",  "description": "",  "main": "index.js",  "scripts": {    "test": "echo \"Error: no test specified\" && exit 1"  },  "author": "",  "license": "ISC"}

Next run the following to install FFmpeg:

npm i -s ffmpeg-static

And then create a new src folder with main.js inside.

mkdir srctouch src/main.js

Next make a data folder to store the input and output file:

mkdir data

Download the following sample file and put it into data folder. Rename it to input.mkv

https://samples.tdarr.io/api/v1/samples/sample__240__libx264__aac__30s__video.mkv

Code

Open up main.js and add the following:

const ffmpegPath = require('ffmpeg-static');const childProcess = require('child_process');
const inputFile = `${process.cwd()}/data/input.mkv`;const outputFile = `${process.cwd()}/data/output.mkv`;
// spawn an ffmpeg processconst child = childProcess.spawn(    ffmpegPath,    // note, args must be an array when using spawn    [        '-i',        `${inputFile}`,        // copy over the input streams of the input file to the output file        '-map',        '0',        '-c',        'copy',        // transcode the file into hevc from h264        '-c:v',        'libx265',        `${outputFile}`,    ],);
child.on('error', () => {    // catches execution error (bad file)    console.log(`Error executing binary: ${ffmpegPath}`);});
child.stdout.on('data', (data) => {    console.log(data.toString());});
child.stderr.on('data', (data) => {    console.log(data.toString());});
child.on('close', (code) => {    console.log(`Process exited with code: ${code}`);    if (code === 0) {        console.log(`FFmpeg finished successfully`);    } else {        console.log(`FFmpeg encountered an error, check the console output`);    }});

Run node ./src/main.js and FFmpeg should successfully transcode the file.

info

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https://tdarr.io/download/