estliberitas / express-duration-app

Node.js express application which allows to calculate duration of videos without full uploading them to server side.

Video duration calculator application

This Express application allows you to calculate total duration for given video files without uploading them (almost). Instead of full uploading it reads chunks from client (i.e. browser) using HTML5 File API & WebSockets and passes that data to ffprobe command-line utility.

Requirements

• Node.js (>=0.10.x)
• ffprobe tool (>=1.x). Usually comes with ffmpeg package

Installation & running

1. $ git clone git://github.com:estliberitas/express-duration-app.git
2. $ cd express-duration-app
3. $ npm install
4. $ PORT=1337 node app.js
5. Open http://127.0.0.1:3000/ in browser (which hopefully supports websockets)

How it works

• When page is opened, WebSocket connection is established using socket.io.
• Once one presses Browse button and selects one or more video files, client sends get duration request via websockets with list of files.
• For each file backend generates URL http://127.0.0.1:PORT/data/{SOCKET_ID}/{FILENAME} and spawns ffprobe [options] URL.
• When ffprobe makes HTTP request to URL, backend handler requests file data from client via websockets using range specified by ffprobe in HTTP request Range header.