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1. Introduction

1.1 What is the VideoLAN project ?

VideoLAN is a complete software solution for video streaming, developed by students at the Ecole Centrale Paris and contributors from all over the world, under the General Public License (GPL). It has been designed for streaming MPEG 1 and MPEG 2 videos on local area networks (LAN), but it can be extended to metropolitan or wide area networks (MAN, WAN), thanks to the multicast technology.

The VideoLAN solution includes a server, which can stream video from various sources (file, DVD, satellite and MPEG 2 encoder), a client, which can receive, decode and display MPEG 1 and MPEG 2 streams and, if necessary, a channel server which tells automatically to the client the parameters needed to receive the stream.

Here is an illustration of the complete VideoLAN solution :

        DVD --->-                 Unicast/Broadcast/Multicast
                  \                           ---
        File --->--     --------            /     \            --------
                   |->-| Server |=====>====|  LAN  |---->-----| Client |
     Satellite ->--    | (VLS)  |           \     /           | (VLC)  |
                  /     --------              ---              --------
       MPEG2 -->-                              ^
      encoder                                  |
                                               v
                                        ----------------
                                       | Channel Server |
                                       |    (VLCS)      |
                                        ----------------

1.2 About this Howto

This Howto is designed to explain how to use the complete VideoLAN solution. It presents the different possibilities of VideoLAN and which configuration you should adopt depending on the configuration of your network.

1.3 Legal notice

Copyright (╘) 2002 by the VideoLAN project.

Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.1 or any later version published by the Free Software Foundation ; with no Invariant Sections, with no Front-Cover Texts, and with no Back-Cover Texts. The text of the license can be found on http://www.gnu.org/copyleft/fdl.html.

1.4 The documentation of the project

There are four main documents :

• the VideoLAN Quickstart,
• this VideoLAN HOWTO,
• the VideoLAN Server user guide,
• the VideoLAN Client HOWTO.

The up-to-date version of these documents can be found on the VideoLAN Web Site.

1.5 Requirements

The skills

Basic skills on Linux and Network should be enough.

The VideoLAN Client

The VideoLAN Client (vlc) works on many platforms : Linux, Windows, Mac OS X, BeOS, *BSD, Solaris, iPaq, QNX. It can read MPEG 1, MPEG 2 and MPEG 4 / DivX files from a hard disk or a CD-ROM drive, read DVDs and VCDs. But the most important function is that it can read MPEG 1, MPEG 2 and DVDs streamed on a network. vlc requires at least a Pentium 400Mhz with 32MB of RAM.

The VideoLAN Server and mini-Server

The VideoLAN Server (vls) can read videos from :

• an MPEG 1 or MPEG 2 file stored on a hard drive or on a CD,
• a DVD located in a local DVD drive or copied on a hard drive,
• a satellite card,
• an MPEG encoding card ;

and stream it on the network.

A Pentium 100 MHz with 32 MB of memory should be enough to send one stream on the network. When streaming a lot of videos stored on a hard drive, the actual limitation is not the processor but the hard drive and the network connection.

vls works under Linux, Solaris and Windows. Currently, the Windows vls version of is only able to stream a video from a file.

The VideoLAN mini-Server (vlms) is only capable of streaming an MPEG file. vlms works on Linux only. It is easier to install and configure than vls and should be used mainly for testing purposes.

Get a streamable MPEG file

vls and vlms can stream MPEG 1 or MPEG 2 files that meet two critera :

1. the file must be MPEG PS (Program Stream) or MPEG TS (Transport Stream), that contain video and audio multiplexed. vls and vlms can't stream MPEG ES (Elementary Stream), i.e. a file with only audio or video. In order to know if an MPEG file is MPEG PS, MPEG TS or MPEG ES, read the file with vlc and look at the messages (with the interface : Click on "View" and "Messages", or use the command line "vlc -v") and look for a line :

   module: locking demux module `mpeg_XX'
   

   If XX = ps or XX = ts, then your file is MPEG PS and MPEG TS respectively , and you may be able to stream it. If XX = es, then your file is MPEG ES and is not streamable.
2. the sequence header of the video must repeat itself regularly, which is often the case with MPEG 2, but very rare with MPEG 1. There is no easy way to know if the sequence header is repeated regularly. Files with a .vob extension are normally MPEG 2 files and files with .mpg or .mpeg extension or usually MPEG 1 files.

You can download this streamable MPEG 2 PS file for your tests : ftp://ftp.videolan.org/pub/videolan/streams/presentation/presentation_short.vob.

The VideoLAN Channel Server

The VideoLAN Channel Server (vlcs) is the central architecture that manages the network. There are different versions of vlcs for different kinds of networks. For example, if your network supports multicast, you will use mini-vlcs. If your network doesn't support multicast but supports VLANs, you should use mini VLAN Server. vlcs works on Linux only.

The Network

You will need a network, which can be as small as one ethernet 10 / 100 Mbit/s switch or hub, and as big as the whole Internet ! See if your network supports "multicast". The bandwidth needed is :

• 6 to 9 Mbit/s for a DVD,
• 3 to 4 Mbit/s for an MPEG 1 stream, an MPEG 2 stream (from a satellite or an MPEG 2 encoding card).

1.6 The mailing-lists

If you have problems using VideoLAN, and if you don't find the answer to your problem in the documentation, please look at the online archive of the mailing-lists. There are 3 english-speaking mailing-lists for the users :

• vlc@videolan.org for the questions on vlc,
• vls@videolan.org for the questions on vls and vlms,
• vlcs@videolan.org for the questions on vlcs and the network.

The mailing lists above also have their equivalent for the developers (they also receive the commit mails) :

• vlc-devel@videolan.org for the development of vlc,
• vls-devel@videolan.org for the development of vls and vlms,
• vlcs-devel@videolan.org for the development of vlcs and the network tools.

If you want to subscribe or unsubscribe to the mailing-lists, please go to the VideoLAN Web Site

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