VideoLAN Quickstart Alexis de Lattre Bill Eldridge Anil Daoud Mathieu Gautier Clément Stenac Copyright © 2002, 2003 the VideoLAN project Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 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. Abstract This document describes how to start using VideoLAN quickly. ------------------------------------------------------------------------------- Table of Contents 1._Introduction 1._What_is_the_VideoLAN_project_? 1.1._Overview 1.2._VideoLAN_software 2._What_is_a_codec_? 3._How_can_I_use_VideoLAN_? 3.1._Documentation 3.2._User_support 4._Command_line_usage 4.1._Open_a_terminal 2._VLC,_the_universal_media_player 1._Installing_VLC 1.1._Windows 1.2._BeOS 1.3._Mac_OS_X 1.4._Debian_GNU/Linux 1.5._Linux_Mandrake 1.6._Linux_Redhat 1.7._Compile_the_sources_by_yourself_(for_every_other_OS) 2._Running_VLC 2.1._Read_a_file 2.2._Read_a_DVD_or_a_VCD 2.3._Troubleshooting 3._Stream_and_receive_with_VLC 1._Unicast_an_MPEG-1,_MPEG-2,_or_MPEG-4_/_DivX_file 2._Unicast_a_DVD 3._Multicast_to_several_VLC's 4._Video_On_Demand 1._Overview 2._On_the_server_side 3._On_the_client_side 5._Add_a_channel_information_service 1._Send_announces_when_streaming_with_VLC 2._Start_VLC(s)_on_the_client(s) 6._Conclusion A._GNU_Free_Documentation_License 1._PREAMBLE 2._APPLICABILITY_AND_DEFINITIONS 3._VERBATIM_COPYING 4._COPYING_IN_QUANTITY 5._MODIFICATIONS 6._COMBINING_DOCUMENTS 7._COLLECTIONS_OF_DOCUMENTS 8._AGGREGATION_WITH_INDEPENDENT_WORKS 9._TRANSLATION 10._TERMINATION 11._FUTURE_REVISIONS_OF_THIS_LICENSE 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 Table of Contents 1._What_is_the_VideoLAN_project_? 1.1._Overview 1.2._VideoLAN_software 2._What_is_a_codec_? 3._How_can_I_use_VideoLAN_? 3.1._Documentation 3.2._User_support 4._Command_line_usage 4.1._Open_a_terminal 1.  What is the VideoLAN project ? 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 VideoLAN solution More details about the project can be found on the VideoLAN_Web_site. 1.2.  VideoLAN software 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. 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. 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. 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. 3.  How can I use VideoLAN ? 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 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 documentation_page . You can also have a look at the 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... 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 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 bug_reporting_page . 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. . 4.1.  Open a terminal 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 Windows terminal Note Under Windows, you need to be in the directory where the program is installed to run it. Linux / Unix Open a terminal : Figure 1.3. Linux X terminal Linux X terminal 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 Mac OS X Go to Applications, open the folder Utilities and double-click on Terminal : Figure 1.4. Mac OS X terminal Mac OS X terminal 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 ./ . BeOS In the deskbar, go to Application and then Terminal : Figure 1.5. BeOS terminal BeOS terminal 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 Table of Contents 1._Installing_VLC 1.1._Windows 1.2._BeOS 1.3._Mac_OS_X 1.4._Debian_GNU/Linux 1.5._Linux_Mandrake 1.6._Linux_Redhat 1.7._Compile_the_sources_by_yourself_(for_every_other_OS) 2._Running_VLC 2.1._Read_a_file 2.2._Read_a_DVD_or_a_VCD 2.3._Troubleshooting 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. 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. 1.2. BeOS Download the Zip file from the VLC_BeOS_download_page. Unzip the file in a directory to install VLC. 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). 1.4. Debian GNU/Linux 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 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 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: testing_page 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 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 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. 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. 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 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.  Running VLC 2.1.  Read a file % vlc -vvv video1.xyz where video1.xyz is the name of the file you want to play. 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. 2.3.  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 vlc_FAQ and have a look at the 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 Table of Contents 1._Unicast_an_MPEG-1,_MPEG-2,_or_MPEG-4_/_DivX_file 2._Unicast_a_DVD 3._Multicast_to_several_VLC's 1.  Unicast an MPEG-1, MPEG-2, or MPEG-4 / DivX file 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). Start VLC on the client % vlc -vvv udp: 2.  Unicast a DVD 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. Start VLC on the server % vlc -vvv udp: 3.  Multicast to several VLC's 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. 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). Start VLC on the client(s) % vlc -vvv udp:@239.255.12.42 Chapter 4.  Video On Demand Table of Contents 1._Overview 2._On_the_server_side 3._On_the_client_side 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. 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. 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 Table of Contents 1._Send_announces_when_streaming_with_VLC 2._Start_VLC(s)_on_the_client(s) 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. 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. 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 documentation_page. Appendix A. GNU Free Documentation License Version 1.2, November 2002 Table of Contents 1._PREAMBLE 2._APPLICABILITY_AND_DEFINITIONS 3._VERBATIM_COPYING 4._COPYING_IN_QUANTITY 5._MODIFICATIONS 6._COMBINING_DOCUMENTS 7._COLLECTIONS_OF_DOCUMENTS 8._AGGREGATION_WITH_INDEPENDENT_WORKS 9._TRANSLATION 10._TERMINATION 11._FUTURE_REVISIONS_OF_THIS_LICENSE 12._ADDENDUM:_How_to_use_this_License_for_your_documents 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. 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. 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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. 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. 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". 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. 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. 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. 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. 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. 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.