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VideoLAN Quickstart
Alexis de Lattre
Bill Eldridge
Anil Daoud
Mathieu Gautier
Clément Stenac
Copyright © 2002, 2003 the VideoLAN project
This document describes how to start using VideoLAN quickly.
Permission is granted to copy, distribute and/or modify this document under
the terms of the GNU Free Documentation License, Version 1.2 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 in the appendix GNU Free Documentation License.
-----------------------------------------------------------------------------
Table of Contents
1. Introduction
1.1. What is the VideoLAN project ?
1.2. What is a codec ?
1.3. How can I use VideoLAN ?
1.4. Command line usage
2. VLC, the universal media player
2.1. Installing VLC
2.2. Running VLC
3. Stream and receive with VLC
3.1. Unicast an MPEG-1, MPEG-2, or MPEG-4 / DivX file
3.2. Unicast a DVD
3.3. Multicast to several VLC's
4. Video On Demand
4.1. Overview
4.2. On the server side
4.3. On the client side
5. Add a channel information service
5.1. Send announces when streaming with VLC
5.2. Start VLC(s) on the client(s)
6. Conclusion
A. GNU Free Documentation License
A.1. PREAMBLE
A.2. APPLICABILITY AND DEFINITIONS
A.3. VERBATIM COPYING
A.4. COPYING IN QUANTITY
A.5. MODIFICATIONS
A.6. COMBINING DOCUMENTS
A.7. COLLECTIONS OF DOCUMENTS
A.8. AGGREGATION WITH INDEPENDENT WORKS
A.9. TRANSLATION
A.10. TERMINATION
A.11. FUTURE REVISIONS OF THIS LICENSE
A.12. ADDENDUM: How to use this License for your documents
List of Figures
1-1. Global VideoLAN solution
1-2. Windows terminal
1-3. Linux X terminal
1-4. Mac OS X terminal
1-5. BeOS terminal
-----------------------------------------------------------------------------
Chapter 1. Introduction
1.1. What is the VideoLAN project ?
1.1.1. Overview
VideoLAN is a complete software solution for video streaming, developed by
students of the Ecole Centrale Paris and developers from all over the world,
under the GNU General Public License (GPL). VideoLAN is designed to stream
MPEG videos on high bandwidth networks.
The VideoLAN solution includes :
  * VLS (VideoLAN Server), which can stream MPEG-1, MPEG-2 and MPEG-4 files,
DVDs, digital satellite channels, digital terrestial television channels
and live videos on the network in unicast or multicast,
  * VLC (initially VideoLAN Client), which can be used as a server to stream
MPEG-1, MPEG-2 and MPEG-4 files, DVDs and live videos on the network in
unicast or multicast ; or used as a client to receive, decode and display
MPEG streams under multiple operating systems.
Here is an illustration of the complete VideoLAN solution :
Figure 1-1. Global VideoLAN solution
[global-diagram]
More details about the project can be found on the [http://www.videolan.org/]
VideoLAN Web site.
-----------------------------------------------------------------------------
1.1.2. VideoLAN software
1.1.2.1. VLC
VLC works on many platforms : Linux, Windows, Mac OS X, BeOS, *BSD, Solaris,
Familiar Linux, Yopy/Linupy and QNX. It can read :
  * MPEG-1, MPEG-2 and MPEG-4 / DivX files from a hard disk, a CD-ROM drive,
...
  * DVDs and VCDs,
  * from a satellite card (DVB-S),
  * MPEG-1, MPEG-2 and MPEG-4 streams from the network sent by VLS or VLC's
stream output.
VLC can also be used as a server to stream :
  * MPEG-1, MPEG-2 and MPEG-4 / DivX files,
  * DVDs,
  * from an MPEG encoding card,
to :
  * one machine (i.e. to one IP address) : this is called unicast,
  * a dynamic group of machines that the clients can join or leave (i.e. to a
multicast IP address) : this is called multicast,
in IPv4 or IPv6 .
To get the complete list of VLC's possibilities on each plateform supported,
see the VLC features page.
Note VLC doesn't work on Mac OS 9, and will probably never do.
-----------------------------------------------------------------------------
1.1.2.2. VLS
VLS can stream :
  *  an MPEG-1, MPEG-2 or MPEG-4 files stored on a hard drive or on a CD,
  *  a DVD located in a local DVD drive or copied on a hard disk,
  *  a satellite card (DVB-S) or a digital terrestial television card (DVB-T)
,
  *  an MPEG encoding card ;
to:
  * one machine (i.e. to one IP address) : this is called unicast,
  * a dynamic group of machines that the clients can join or leave (i.e. to a
multicast IP address) : this is called multicast,
in IPv4 or IPv6 .
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 and Windows. To get the complete list of VLS's
possibilities on each plateform supported, see the streaming features page.
-----------------------------------------------------------------------------
1.1.2.3. Mini-SAP-server
You can add a channel information service based on the SAP/SDP standard to
the VideoLAN solution. The mini-SAP-server sends announces about the
multicast programs on the network in IPv4 or IPv6, and VLCs receive these
annouces and automatically add the programs announced to their playlist.
The mini-SAP-server works under Linux and Mac OS X.
-----------------------------------------------------------------------------
1.2. What is a codec ?
To fully understand the VideoLAN solution, you must understand the
difference between a codec and a container format
  *  A codec is a compression algorithm, used to reduce the size of a stream.
There are audio codecs and video codecs. MPEG-1, MPEG-2, MPEG-4, Vorbis,
DivX, ... are codecs
  *  A container format contains one or several streams already encoded by
codecs. Very often, there is an audio stream and a video one. AVI, Ogg,
MOV, ASF, ... are container formats. The streams contained can be encoded
using different codecs. In a perfect world, you could put any codec in
any container format. Unfortunately, there are some incompatibilities.
You can find a matrix of possible codecs and container formats on the
features page
To decode a stream, VLC first demuxes it. This means that it reads the
container format and separates audio, video, and subtitles, if any. Then,
each of these are passed decoders that do the mathematical processing to
decompress the streams .
There is a particular thing about MPEG:
  *  MPEG is a codec. There are several versions of it, called MPEG-1,
MPEG-2, MPEG-4, ...
  * MPEG is also a container format, sometimes refered to as MPEG System.
There are several types of MPEG: ES, PS, and TS
When you play an MPEG video from a DVD, for instance, the MPEG stream is
actually composed of several streams (called Elementary Streams, ES):
there is one stream for video, one for audio, another for subtitles, and
so on. These different streams are mixed together into a single Program
Stream (PS). So, the .VOB files you can find in a DVD are actually
MPEG-PS files. But this PS format is not adapted for streaming video
through a network or by satellite, for instance. So, another format
called Transport Stream (TS) was designed for streaming MPEG videos
through such channels.
-----------------------------------------------------------------------------
1.3. How can I use VideoLAN ?
1.3.1. Documentation
The user documentation of VideoLAN is made up of 4 documents :
  *  the VideoLAN Quickstart. This document will give you a quick overview of
of VLC, VLC's stream output, the Video On Demand solution and the channel
information service system.
  *  the VideoLAN HOWTO. This document is the complete guide of the VideoLAN
streaming solution.
  *  the VLC user guide. This document is the complete guide for VLC.
  *  the VLS user guide. This document is the complete guide for VLS.
  *  the VideoLAN FAQ. This document contains Frequently Asked Questions
about VideoLAN.
The latest version of these documents can be found on the [http://
www.videolan.org/doc/] documentation page .
You can also have a look at the [http://wiki.videolan.org] VideoLAN Wiki.
This is a website that everyone can change. We use it to document everything
that is not in the "official" documentation: the tips and tricks for each
O.S., the graphical interfaces, etc...
-----------------------------------------------------------------------------
1.3.2. User support
If you have problems using VideoLAN, and if you don't find the answer to
your problems in the documentation, please look at the online archive of the
mailing-lists. There are two English-speaking mailing-lists for the users :
  * vlc@videolan.org for the questions on VLC ,
  * streaming@videolan.org for the questions on VLS, mini-SAP-server and the
network .
If you want to subscribe or unsubscribe to the mailing-lists, please go to
the [http://www.videolan.org/support/lists.html] mailing-list page.
You can also talk with VideoLAN users and developers on IRC : server
irc.freenode.net, channel #videolan .
If you find a bug, please follow the instructions on the [http://
www.videolan.org/support/bug-reporting.html] bug reporting page .
-----------------------------------------------------------------------------
1.4. Command line usage
  *  VLC has many different graphical interfaces, that are organized quite
differently in order to be in harmony with the guidelines of each
operating system supported. Documenting the use of each graphical
interface is too long, and some features are only available via the
command line interface. Therefore we decided to document only the command
line interface, but in many cases it shoud be easy to guess how to use
the graphical interface for the same use !
  *  VLS has a command line and a telnet interface, but no graphical
interface !
All the commands that show up in this document should be typed inside a
terminal. .
-----------------------------------------------------------------------------
1.4.1. Open a terminal
1.4.1.1. Windows
Click on Start, Run and type :
  * cmd Enter (Windows 2000 / XP),
  * command Enter (Windows 95 / 98 / ME).
The terminal appears Le terminal apparait
Figure 1-2. Windows terminal
[terminal-windows]
Note Under Windows, you need to be in the directory where the program is
installed to run it.
-----------------------------------------------------------------------------
1.4.1.2. Linux / Unix
Open a terminal :
Figure 1-3. Linux X terminal
[terminal-linux]
In the documentation, we adopt the following conventions for the Unix
commands :
  *  commands that should be typed as root have a # prompt :
# command_to_be_typed_as_root
  *  commands that should be typed as a regular user have a % prompt :
% command_to_be_typed_as_regular_user
-----------------------------------------------------------------------------
1.4.1.3. Mac OS X
Go to Applications, open the folder Utilities and double-click on Terminal
:
Figure 1-4. Mac OS X terminal
[terminal-macosx]
Note Under Mac OS X, you need to be in the directory where the program is
installed to run it, and start the command with ./ .
-----------------------------------------------------------------------------
1.4.1.4. BeOS
In the deskbar, go to Application and then Terminal :
Figure 1-5. BeOS terminal
[terminal-beos]
Note Under BeOS, you need to be in the directory where the program is
installed to run it, and start the command with ./ .
-----------------------------------------------------------------------------
Chapter 2. VLC, the universal media player
2.1. Installing VLC
There are VLC binaries available for the many OSes, but not for all
supported OSes. If there are no binaries for your OS or if you want to change
the default settings, you can compile VLC from sources.
-----------------------------------------------------------------------------
2.1.1. Windows
VLC works under Windows 95/98/ME/2000/XP. Download the self-extracting file
from the VLC Windows download page. Launch the .exe to install VLC.
-----------------------------------------------------------------------------
2.1.2. BeOS
Download the Zip file from the VLC BeOS download page. Unzip the file in a
directory to install VLC.
-----------------------------------------------------------------------------
2.1.3. Mac OS X
Download the Mac OS X package from the VLC MacOS X download page .
Double-click on the icon of the package : an icon will appear on your
Desktop, right beside your drive(s). Open it and drag the VLC application
from the resulting window to the place where you want to install it (it
should be /Applications).
-----------------------------------------------------------------------------
2.1.4. Debian GNU/Linux
2.1.4.1. Debian stable (woody)
Add the following lines to your /etc/apt/sources.list:
deb http://www.videolan.org/pub/videolan/debian $(ARCH)/
deb-src http://www.videolan.org/pub/videolan/debian sources/
Then, for a normal install, do:
# apt-get update
# apt-get install gnome-vlc libdvdcss2
-----------------------------------------------------------------------------
2.1.4.2. Debian unstable (sid)
Add the following lines to your /etc/apt/sources.list:
deb http://www.videolan.org/pub/videolan/debian $(ARCH)/
deb-src http://www.videolan.org/pub/videolan/debian sources/
Then, for a normal install, do:
# apt-get update
# apt-get install wxvlc libdvdcss2
-----------------------------------------------------------------------------
2.1.4.3. Debian testing (sarge)
You should not be using Debian testing unless you perfectly know what you
are doing. It is almost impossible to support Debian testing and there are no
plans to do it. For more informations on Debian testing, please look: [http:/
/www.debian.org/devel/testing] testing page
-----------------------------------------------------------------------------
2.1.5. Linux Mandrake
There are VLC packages for Mandrake 9.1 and cooker.
To install them, add the following sources for either Mandrake 9.1 or
Cooker (you can use [http://plf.zarb.org/~nanardon/] Easy urpmi for that):
contrib from the core distribution and plf (Penguin Liberation Front) from
the external add-ons.
Then install the required packages with urpmi:
# urpmi libdvdcss2 libdvdplay0 wxvlc vlc-plugin-a52 vlc-plugin-ogg vlc-plugin-mad
-----------------------------------------------------------------------------
2.1.6. Linux Redhat
Download the RPM package vlc and the packages listed in the required
libraries and codecs section (the other packages are just optional) from the
VLC Red Hat download page and put them all into the same directory.
Then install the RPM packages you have downloaded:
# rpm -U *.rpm
If you have not installed all the RPM packages included with your
distribution, you may be asked to install a few of them first.
-----------------------------------------------------------------------------
2.1.7. Compile the sources by yourself (for every other OS)
The method below is for any Unix system supported by VLC, for which there is
no packages available. It explains how to compile and install VLC and the
needed libraries from their source code.
You can also compile VLC under Linux this way if you want to modify the
default supported modules.
-----------------------------------------------------------------------------
2.1.7.1. Install the libraries
Many libraries are needed :
  * libdvbpsi (compulsory) ,
  * mpeg2dec (compulsory) ,
  * libdvdcss if you want to be able to read encrypted DVDs ,
  * libdvdplay if you want to have DVD menu navigation ,
  * a52dec if you want to be able to decode the AC3 (i.e. A52) sound format
often used in DVDs ,
  * ffmpeg, libmad, faad2 if you want to read MPEG 4 / DivX files ,
  * libogg & libvorbis if you want to read Ogg Vorbis files .
Download the libraries from the VLC sources download page.
For each library :
  *  uncompress :
% tar xvzf library.tar.gz
or
% tar xvjf library.tar.bz2
  *  configure :
% cd library
% ./configure
  *  compile and install :
% make
# make install
Check that the configuration file /etc/ld.so.conf contains the following
line :
/usr/local/lib
If the line is not present, add-it and then run (as root):
# ldconfig
-----------------------------------------------------------------------------
2.1.7.2. Install VLC
Download the sources of the lastest release : get the file
vlc-version.tar.gz from the VLC sources download page. Uncompress-it :
% tar xvzf vlc-version.tar.gz
% cd vlc-version
To get the list of configuration options, do :
% ./configure --help
Please note that all the modules are described in the Modules section of the
VLC User Guide .
Examples of very simple configurations:
  *  if you want a basic VLC, do :
% ./configure
  *  if you want the Gnome interface instead of the GTK interface (you will
need the developement packages of Gnome) :
% ./configure --enable-gnome
Then, compile and install :
% make
% su
Password: [Root Password]
# make install
Please note that the installation (make install command) is not mandatory.
You can execute VLC from where you compiled it.
-----------------------------------------------------------------------------
2.2. Running VLC
2.2.1. Read a file
% vlc -vvv video1.xyz
where video1.xyz is the name of the file you want to play.
-----------------------------------------------------------------------------
2.2.2. Read a DVD or a VCD
% vlc -vvv dvd:/dev/dvd
where /dev/dvd is the name of your drive (put D: under Windows if D is the
letter of your DVD drive).
Note If you are running Linux, you must have write access to the device
corresponding to your DVD drive. For that, you should be in the disk or
cdrom group (look at the permissions in /dev). If you're not, add
yourself to the group :
# adduser your_login disk_or_cdrom
and then restart your session.
-----------------------------------------------------------------------------
2.2.3. Troubleshooting
If VLC doesn't work for you, try to spot an error message in the logs that
are printed in the terminal.
Then, read the [http://www.videolan.org/doc/faq/] vlc FAQ and have a look at
the [http://bugzilla.videolan.org/] Bugzilla to see if it is a known issue.
If you can't find out the problem, explain it in English in the mailing-list
vlc@videolan.org and copy-paste in your mail the messages of the message
window.
-----------------------------------------------------------------------------
Chapter 3. Stream and receive with VLC
3.1. Unicast an MPEG-1, MPEG-2, or MPEG-4 / DivX file
3.1.1. Start VLC on the server
% vlc -vvv video1.xyz --sout udp:client.example.org
where video1.xyz is the file you want to stream and client.example.org is the
DNS name of the client you want to stream to (you can put an IP address
instead).
-----------------------------------------------------------------------------
3.1.2. Start VLC on the client
% vlc -vvv udp:
-----------------------------------------------------------------------------
3.2. Unicast a DVD
3.2.1. Start VLC on the server
% vlc -vvv dvdold:/dev/dvd --sout udp:client.example.org
where /dev/dvd is the name of your DVD drive (put D: under Windows if D is
the letter of your DVD drive) or the directory where you copied your DVD, and
client.example.org is the DNS name of the client you want to stream to (you
can put an IP address instead).
Note Under Unix/Linux, you must have write access to the device corresponding
to your DVD drive. For that, you should be in the disk or cdrom group
(look at the permissions in /dev). If you're not, add yourself to the
group :
# adduser your_login disk_or_cdrom
and then restart your session.
-----------------------------------------------------------------------------
3.2.2. Start VLC on the server
% vlc -vvv udp:
-----------------------------------------------------------------------------
3.3. Multicast to several VLC's
3.3.1. What is multicast ?
Multicast is a norm implemented in all modern network hardware (switches,
routers, ...). It provides an intelligent manner to send a stream to a
dynamic group of machines. If you want to use multicast, make sure that all
your network hardware support it.
In multicast streaming, the stream is sent to a multicast IP address (the IP
addresses reserved for this purpose are from 224.0.0.0 to 239.255.255.255).
Then, any machine on the network can join the multicast group by sending a
request on the network, and it will automatically receive the stream. When it
sends a request to leave the group, it will automatically stop receiving the
stream. The advantage of multicast streaming is that only the machines that
want to receive the stream actually receive it, and the streaming server only
sends one stream even if there are multiple clients receiving it.
-----------------------------------------------------------------------------
3.3.2. Start VLC on the server
% vlc -vvv video1.xyz --sout udp:239.255.12.42 --ttl 12
where video1.xyz is the file you want to stream (remplace it with dvdold:/dev
/dvd under Unix or dvdold:D: under Windows if you want to multicast a DVD),
239.255.12.42 is the multicast IP address you want to stream on and 12 is the
value of the TTL (Time To Live) of your IP packets (which means that the
multicast stream will be able to cross 12 routers).
-----------------------------------------------------------------------------
3.3.3. Start VLC on the client(s)
% vlc -vvv udp:@239.255.12.42
-----------------------------------------------------------------------------
Chapter 4. Video On Demand
4.1. Overview
With Video On Demand (VOD), the user can start the video when he wants, make
pauses, go forward and back in the video. It is of course the best in video
streaming and the dream for every user.
VOD is a very big consumer of resources for the server and the network. VOD
is unicast, not multicast : this means that the network and server resources
needed are directly proportional to the number of clients.
The design of VideoLAN's VOD solution is very simple. The idea is to do HTTP
streaming, i.e. stream an MPEG video encapsulated in HTTP. The regulation of
the bitrate between the client and the server is done automatically by TCP.
With HTTP version 1.1, there is the possibility to seek in a file downloaded,
that's what we use to seek in the video.
-----------------------------------------------------------------------------
4.2. On the server side
On the VOD server, you need a running Web server. For example, you can use a
Linux server running Apache. Other operating systems and other Web servers
should work too, but we have never tested.
Make your MPEG-1, MPEG-2 or MPEG-4 / DivX files available to the clients on
the Web server.
For example, we have a Web server whose DNS name is localserver. On this
server, we put an MPEG file video1.mpg which will be available to the clients
at the URL http://localserver/video1.mpg.
-----------------------------------------------------------------------------
4.3. On the client side
% vlc -vvv http://localserver/video1.mpg
VLC starts to read the stream nearly immediately and you can seek in the
stream, make pauses, etc... as if the stream was a local file.
-----------------------------------------------------------------------------
Chapter 5. Add a channel information service
Typing multicast addresses is not very fun... that's why you need a channel
information service ! VideoLAN has implemented a channel information service
based on the SAP/SDP standard. VLC's stream output can send SAP announces
when streaming (on the multicast address 224.2.127.254 reserved for this
purpose). On the client side, VLCs receive these annouces and automatically
add the programs announced to their playlist.
-----------------------------------------------------------------------------
5.1. Send announces when streaming with VLC
To send announces with VLC, you need to use the complex syntax of VLC's
stream output, like this:
% vlc -vvv video1.xyz --sout '#standard{access=udp,url=239.255.12.42,sap="Test Stream"}' --ttl 12
where video1.xyz is the file you want to stream, 239.255.12.42 is the
multicast IP address you want to stream on, Test Stream is the name that will
be used for this program in the SAP announces and 12 is the value of the TTL
(Time To Live) of the stream and of the SAP announces.
-----------------------------------------------------------------------------
5.2. Start VLC(s) on the client(s)
Start VLC with the sap interface:
% vlc -vvv --extraintf sap
Then open the playlist: you should see the names of the programs announced in
SAP. When you double-click on the name of a program, VLC will subscribe to
the multicast address and start to play the stream !
-----------------------------------------------------------------------------
Chapter 6. Conclusion
VideoLAN can do much more than what is explained in this Quickstart. For
example, you can use VLC to display image walls or to transcode a stream
on-the-fly. You can also use VLS to stream digital satellite channels and
digital terrestial TV channels. To know about the full possibilities of
VideoLAN, please read the rest of the official documentation, that you can
find on the [http://www.videolan.org/doc/] documentation page.
-----------------------------------------------------------------------------
Appendix A. GNU Free Documentation License
Version 1.2, November 2002
Copyright (C) 2000,2001,2002 Free Software Foundation, Inc. 59 Temple
Place, Suite 330, Boston, MA 02111-1307 USA Everyone is permitted to copy
and distribute verbatim copies of this license document, but changing it
is not allowed.
-----------------------------------------------------------------------------
A.1. PREAMBLE
The purpose of this License is to make a manual, textbook, or other
functional and useful document "free" in the sense of freedom: to assure
everyone the effective freedom to copy and redistribute it, with or without
modifying it, either commercially or noncommercially. Secondarily, this
License preserves for the author and publisher a way to get credit for their
work, while not being considered responsible for modifications made by
others.
This License is a kind of "copyleft", which means that derivative works of
the document must themselves be free in the same sense. It complements the
GNU General Public License, which is a copyleft license designed for free
software.
We have designed this License in order to use it for manuals for free
software, because free software needs free documentation: a free program
should come with manuals providing the same freedoms that the software does.
But this License is not limited to software manuals; it can be used for any
textual work, regardless of subject matter or whether it is published as a
printed book. We recommend this License principally for works whose purpose
is instruction or reference.
-----------------------------------------------------------------------------
A.2. APPLICABILITY AND DEFINITIONS
This License applies to any manual or other work, in any medium, that
contains a notice placed by the copyright holder saying it can be distributed
under the terms of this License. Such a notice grants a world-wide,
royalty-free license, unlimited in duration, to use that work under the
conditions stated herein. The "Document", below, refers to any such manual or
work. Any member of the public is a licensee, and is addressed as "you". You
accept the license if you copy, modify or distribute the work in a way
requiring permission under copyright law.
A "Modified Version" of the Document means any work containing the Document
or a portion of it, either copied verbatim, or with modifications and/or
translated into another language.
A "Secondary Section" is a named appendix or a front-matter section of the
Document that deals exclusively with the relationship of the publishers or
authors of the Document to the Document's overall subject (or to related
matters) and contains nothing that could fall directly within that overall
subject. (Thus, if the Document is in part a textbook of mathematics, a
Secondary Section may not explain any mathematics.) The relationship could be
a matter of historical connection with the subject or with related matters,
or of legal, commercial, philosophical, ethical or political position
regarding them.
The "Invariant Sections" are certain Secondary Sections whose titles are
designated, as being those of Invariant Sections, in the notice that says
that the Document is released under this License. If a section does not fit
the above definition of Secondary then it is not allowed to be designated as
Invariant. The Document may contain zero Invariant Sections. If the Document
does not identify any Invariant Sections then there are none.
The "Cover Texts" are certain short passages of text that are listed, as
Front-Cover Texts or Back-Cover Texts, in the notice that says that the
Document is released under this License. A Front-Cover Text may be at most 5
words, and a Back-Cover Text may be at most 25 words.
A "Transparent" copy of the Document means a machine-readable copy,
represented in a format whose specification is available to the general
public, that is suitable for revising the document straightforwardly with
generic text editors or (for images composed of pixels) generic paint
programs or (for drawings) some widely available drawing editor, and that is
suitable for input to text formatters or for automatic translation to a
variety of formats suitable for input to text formatters. A copy made in an
otherwise Transparent file format whose markup, or absence of markup, has
been arranged to thwart or discourage subsequent modification by readers is
not Transparent. An image format is not Transparent if used for any
substantial amount of text. A copy that is not "Transparent" is called
"Opaque".
Examples of suitable formats for Transparent copies include plain ASCII
without markup, Texinfo input format, LaTeX input format, SGML or XML using a
publicly available DTD, and standard-conforming simple HTML, PostScript or
PDF designed for human modification. Examples of transparent image formats
include PNG, XCF and JPG. Opaque formats include proprietary formats that can
be read and edited only by proprietary word processors, SGML or XML for which
the DTD and/or processing tools are not generally available, and the
machine-generated HTML, PostScript or PDF produced by some word processors
for output purposes only.
The "Title Page" means, for a printed book, the title page itself, plus such
following pages as are needed to hold, legibly, the material this License
requires to appear in the title page. For works in formats which do not have
any title page as such, "Title Page" means the text near the most prominent
appearance of the work's title, preceding the beginning of the body of the
text.
A section "Entitled XYZ" means a named subunit of the Document whose title
either is precisely XYZ or contains XYZ in parentheses following text that
translates XYZ in another language. (Here XYZ stands for a specific section
name mentioned below, such as "Acknowledgements", "Dedications",
"Endorsements", or "History".) To "Preserve the Title" of such a section when
you modify the Document means that it remains a section "Entitled XYZ"
according to this definition.
The Document may include Warranty Disclaimers next to the notice which states
that this License applies to the Document. These Warranty Disclaimers are
considered to be included by reference in this License, but only as regards
disclaiming warranties: any other implication that these Warranty Disclaimers
may have is void and has no effect on the meaning of this License.
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A.3. VERBATIM COPYING
You may copy and distribute the Document in any medium, either commercially
or noncommercially, provided that this License, the copyright notices, and
the license notice saying this License applies to the Document are reproduced
in all copies, and that you add no other conditions whatsoever to those of
this License. You may not use technical measures to obstruct or control the
reading or further copying of the copies you make or distribute. However, you
may accept compensation in exchange for copies. If you distribute a large
enough number of copies you must also follow the conditions in section 3.
You may also lend copies, under the same conditions stated above, and you may
publicly display copies.
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A.4. COPYING IN QUANTITY
If you publish printed copies (or copies in media that commonly have printed
covers) of the Document, numbering more than 100, and the Document's license
notice requires Cover Texts, you must enclose the copies in covers that
carry, clearly and legibly, all these Cover Texts: Front-Cover Texts on the
front cover, and Back-Cover Texts on the back cover. Both covers must also
clearly and legibly identify you as the publisher of these copies. The front
cover must present the full title with all words of the title equally
prominent and visible. You may add other material on the covers in addition.
Copying with changes limited to the covers, as long as they preserve the
title of the Document and satisfy these conditions, can be treated as
verbatim copying in other respects.
If the required texts for either cover are too voluminous to fit legibly, you
should put the first ones listed (as many as fit reasonably) on the actual
cover, and continue the rest onto adjacent pages.
If you publish or distribute Opaque copies of the Document numbering more
than 100, you must either include a machine-readable Transparent copy along
with each Opaque copy, or state in or with each Opaque copy a
computer-network location from which the general network-using public has
access to download using public-standard network protocols a complete
Transparent copy of the Document, free of added material. If you use the
latter option, you must take reasonably prudent steps, when you begin
distribution of Opaque copies in quantity, to ensure that this Transparent
copy will remain thus accessible at the stated location until at least one
year after the last time you distribute an Opaque copy (directly or through
your agents or retailers) of that edition to the public.
It is requested, but not required, that you contact the authors of the
Document well before redistributing any large number of copies, to give them
a chance to provide you with an updated version of the Document.
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A.5. MODIFICATIONS
You may copy and distribute a Modified Version of the Document under the
conditions of sections 2 and 3 above, provided that you release the Modified
Version under precisely this License, with the Modified Version filling the
role of the Document, thus licensing distribution and modification of the
Modified Version to whoever possesses a copy of it. In addition, you must do
these things in the Modified Version:
A. Use in the Title Page (and on the covers, if any) a title distinct from
that of the Document, and from those of previous versions (which should,
if there were any, be listed in the History section of the Document). You
may use the same title as a previous version if the original publisher of
that version gives permission.
B. List on the Title Page, as authors, one or more persons or entities
responsible for authorship of the modifications in the Modified Version,
together with at least five of the principal authors of the Document (all
of its principal authors, if it has fewer than five), unless they release
you from this requirement.
C. State on the Title page the name of the publisher of the Modified
Version, as the publisher.
D. Preserve all the copyright notices of the Document.
E. Add an appropriate copyright notice for your modifications adjacent to
the other copyright notices.
F. Include, immediately after the copyright notices, a license notice giving
the public permission to use the Modified Version under the terms of this
License, in the form shown in the Addendum below.
G. Preserve in that license notice the full lists of Invariant Sections and
required Cover Texts given in the Document's license notice.
H. Include an unaltered copy of this License.
I. Preserve the section Entitled "History", Preserve its Title, and add to
it an item stating at least the title, year, new authors, and publisher
of the Modified Version as given on the Title Page. If there is no
section Entitled "History" in the Document, create one stating the title,
year, authors, and publisher of the Document as given on its Title Page,
then add an item describing the Modified Version as stated in the
previous sentence.
J. Preserve the network location, if any, given in the Document for public
access to a Transparent copy of the Document, and likewise the network
locations given in the Document for previous versions it was based on.
These may be placed in the "History" section. You may omit a network
location for a work that was published at least four years before the
Document itself, or if the original publisher of the version it refers to
gives permission.
K. For any section Entitled "Acknowledgements" or "Dedications", Preserve
the Title of the section, and preserve in the section all the substance
and tone of each of the contributor acknowledgements and/or dedications
given therein.
L. Preserve all the Invariant Sections of the Document, unaltered in their
text and in their titles. Section numbers or the equivalent are not
considered part of the section titles.
M. Delete any section Entitled "Endorsements". Such a section may not be
included in the Modified Version.
N. Do not retitle any existing section to be Entitled "Endorsements" or to
conflict in title with any Invariant Section.
O. Preserve any Warranty Disclaimers.
If the Modified Version includes new front-matter sections or appendices that
qualify as Secondary Sections and contain no material copied from the
Document, you may at your option designate some or all of these sections as
invariant. To do this, add their titles to the list of Invariant Sections in
the Modified Version's license notice. These titles must be distinct from any
other section titles.
You may add a section Entitled "Endorsements", provided it contains nothing
but endorsements of your Modified Version by various parties--for example,
statements of peer review or that the text has been approved by an
organization as the authoritative definition of a standard.
You may add a passage of up to five words as a Front-Cover Text, and a
passage of up to 25 words as a Back-Cover Text, to the end of the list of
Cover Texts in the Modified Version. Only one passage of Front-Cover Text and
one of Back-Cover Text may be added by (or through arrangements made by) any
one entity. If the Document already includes a cover text for the same cover,
previously added by you or by arrangement made by the same entity you are
acting on behalf of, you may not add another; but you may replace the old
one, on explicit permission from the previous publisher that added the old
one.
The author(s) and publisher(s) of the Document do not by this License give
permission to use their names for publicity for or to assert or imply
endorsement of any Modified Version.
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A.6. COMBINING DOCUMENTS
You may combine the Document with other documents released under this
License, under the terms defined in section 4 above for modified versions,
provided that you include in the combination all of the Invariant Sections of
all of the original documents, unmodified, and list them all as Invariant
Sections of your combined work in its license notice, and that you preserve
all their Warranty Disclaimers.
The combined work need only contain one copy of this License, and multiple
identical Invariant Sections may be replaced with a single copy. If there are
multiple Invariant Sections with the same name but different contents, make
the title of each such section unique by adding at the end of it, in
parentheses, the name of the original author or publisher of that section if
known, or else a unique number. Make the same adjustment to the section
titles in the list of Invariant Sections in the license notice of the
combined work.
In the combination, you must combine any sections Entitled "History" in the
various original documents, forming one section Entitled "History"; likewise
combine any sections Entitled "Acknowledgements", and any sections Entitled
"Dedications". You must delete all sections Entitled "Endorsements".
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A.7. COLLECTIONS OF DOCUMENTS
You may make a collection consisting of the Document and other documents
released under this License, and replace the individual copies of this
License in the various documents with a single copy that is included in the
collection, provided that you follow the rules of this License for verbatim
copying of each of the documents in all other respects.
You may extract a single document from such a collection, and distribute it
individually under this License, provided you insert a copy of this License
into the extracted document, and follow this License in all other respects
regarding verbatim copying of that document.
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A.8. AGGREGATION WITH INDEPENDENT WORKS
A compilation of the Document or its derivatives with other separate and
independent documents or works, in or on a volume of a storage or
distribution medium, is called an "aggregate" if the copyright resulting from
the compilation is not used to limit the legal rights of the compilation's
users beyond what the individual works permit. When the Document is included
an aggregate, this License does not apply to the other works in the aggregate
which are not themselves derivative works of the Document.
If the Cover Text requirement of section 3 is applicable to these copies of
the Document, then if the Document is less than one half of the entire
aggregate, the Document's Cover Texts may be placed on covers that bracket
the Document within the aggregate, or the electronic equivalent of covers if
the Document is in electronic form. Otherwise they must appear on printed
covers that bracket the whole aggregate.
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A.9. TRANSLATION
Translation is considered a kind of modification, so you may distribute
translations of the Document under the terms of section 4. Replacing
Invariant Sections with translations requires special permission from their
copyright holders, but you may include translations of some or all Invariant
Sections in addition to the original versions of these Invariant Sections.
You may include a translation of this License, and all the license notices in
the Document, and any Warrany Disclaimers, provided that you also include the
original English version of this License and the original versions of those
notices and disclaimers. In case of a disagreement between the translation
and the original version of this License or a notice or disclaimer, the
original version will prevail.
If a section in the Document is Entitled "Acknowledgements", "Dedications",
or "History", the requirement (section 4) to Preserve its Title (section 1)
will typically require changing the actual title.
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A.10. TERMINATION
You may not copy, modify, sublicense, or distribute the Document except as
expressly provided for under this License. Any other attempt to copy, modify,
sublicense or distribute the Document is void, and will automatically
terminate your rights under this License. However, parties who have received
copies, or rights, from you under this License will not have their licenses
terminated so long as such parties remain in full compliance.
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A.11. FUTURE REVISIONS OF THIS LICENSE
The Free Software Foundation may publish new, revised versions of the GNU
Free Documentation License from time to time. Such new versions will be
similar in spirit to the present version, but may differ in detail to address
new problems or concerns. See http://www.gnu.org/copyleft/.
Each version of the License is given a distinguishing version number. If the
Document specifies that a particular numbered version of this License "or any
later version" applies to it, you have the option of following the terms and
conditions either of that specified version or of any later version that has
been published (not as a draft) by the Free Software Foundation. If the
Document does not specify a version number of this License, you may choose
any version ever published (not as a draft) by the Free Software Foundation.
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A.12. ADDENDUM: How to use this License for your documents
To use this License in a document you have written, include a copy of the
License in the document and put the following copyright and license notices
just after the title page:
Copyright (c) YEAR YOUR NAME. Permission is granted to copy, distribute
and/or modify this document under the terms of the GNU Free Documentation
License, Version 1.2 or any later version published by the Free Software
Foundation; with no Invariant Sections, no Front-Cover Texts, and no
Back-Cover Texts. A copy of the license is included in the section
entitled "GNU Free Documentation License".
If you have Invariant Sections, Front-Cover Texts and Back-Cover Texts,
replace the "with...Texts." line with this:
with the Invariant Sections being LIST THEIR TITLES, with the
Front-Cover Texts being LIST, and with the Back-Cover Texts being LIST.
If you have Invariant Sections without Cover Texts, or some other combination
of the three, merge those two alternatives to suit the situation.
If your document contains nontrivial examples of program code, we recommend
releasing these examples in parallel under your choice of free software
license, such as the GNU General Public License, to permit their use in free
software.