Difference between revisions of "Documentation:WebPlugin"
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*'''target''' (or one of these alias: '''mrl''', '''filename''', '''src'''): Specifies the source location (URL) of the video to load. | *'''target''' (or one of these alias: '''mrl''', '''filename''', '''src'''): Specifies the source location (URL) of the video to load. | ||
| − | == | + | <object classid="clsid:9BE31822-FDAD-461B-AD51-BE1D1C159921" codebase="http://download.videolan.org/pub/videolan/vlc/last/win32/axvlc.cab"> |
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| − | + | <param name="autostart" value="true" /> | |
| − | + | ||
| − | + | <param name="allowfullscreen" value="false" /> | |
| − | + | ||
| − | + | </object> | |
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=== Normal DOM elements === | === Normal DOM elements === | ||
Revision as of 16:20, 20 December 2014
This Documentation speaks about the VLC media player Web plugins and how to write pages for it.
Contents
Introduction: Building Web pages with Video
The VLC media player webplugins are native browser plugins, similar to Flash or Silverlight plugins and allow playback inside the browser of all the videos that VLC media player can read.
Additionally to viewing video on all pages, you can build custom pages that will use the advanced features of the plugin, using Javascript functions to control playback or extract information from the plugin.
There are 2 main plugins: one is ActiveX for IE, the other is NPAPI for the other browsers. They feature the same amount of features.
In older versions, those plugins were very crashy. We URGE YOU to use VLC 2.0.0 or newer versions.
Browsers support
It has been tested with:
| Mozilla Firefox | 
|
| Internet Explorer | 
|
| Safari | 
|
| Chrome | |
| Konqueror | |
| Opera |
It has been tested on GNU/Linux, Windows and MacOS.
Embed tag attributes
To embed the plugin into a webpage, use the following <embed> template:
<embed type="application/x-vlc-plugin" pluginspage="http://www.videolan.org" />
If you are using vlc version < 2.2.0 with Internet Explorer, use instead the following <object> template:
<object classid="clsid:9BE31822-FDAD-461B-AD51-BE1D1C159921" codebase="http://download.videolan.org/pub/videolan/vlc/last/win32/axvlc.cab"></object>For the declaration of tag attributes, use the tag <param>. Here a example:
<object classid="clsid:9BE31822-FDAD-461B-AD51-BE1D1C159921" codebase="http://download.videolan.org/pub/videolan/vlc/last/win32/axvlc.cab">
<param name="autostart" value="true" />
<param name="allowfullscreen" value="false" />
</object>For compatibility with the mozilla plugin, you can combine both tags:
<object classid="clsid:9BE31822-FDAD-461B-AD51-BE1D1C159921" codebase="http://download.videolan.org/pub/videolan/vlc/last/win32/axvlc.cab" id="vlc">
<embed type="application/x-vlc-plugin" pluginspage="http://www.videolan.org" name="vlc" />
</object>Required elements
These are required attributes for the <embed> tag:
- width: Specifies the width of the plugin.
- height: Specifies the height of the plugin.
- target (or one of these alias: mrl, filename, src): Specifies the source location (URL) of the video to load.
<object classid="clsid:9BE31822-FDAD-461B-AD51-BE1D1C159921" codebase="http://download.videolan.org/pub/videolan/vlc/last/win32/axvlc.cab">
<param name="autostart" value="true" />
<param name="allowfullscreen" value="false" />
</object>
Normal DOM elements
- id: DOM id
- name: DOM name
Javascript API description
The vlc plugin exports several objects that can be accessed for setting and getting information. When used improperly the API's will throw an exception that includes a string that explains what happened. For example when asking for vlc.input.length when there is no playlist item playing.
VLC objects
The vlc plugin knows the following objects:
- audio: Access audio properties.
- input: Access input properties.
- playlist: Access playlist properties.
- subtitle: Access subtitle properties.
- video: Access video properties.
- video.marquee: Access marquee video filter properties.
- video.logo: Access logo video filter properties.
- mediaDescription: Access media info properties (only available in vlc version >= 2.0.2).
The following are deprecated:
- log: Access log properties (only available in vlc version <= 1.0.0-rc1).
- messages: Access to log message properties (only available in vlc version <= 1.0.0-rc1).
- iterator: Access to log iterator properties (only available in vlc version <= 1.0.0-rc1).
- message: Access to log message properties (only available in vlc version <= 1.0.0-rc1).
Example
The following JavaScript code shows howto get a reference to the vlc plugin. This reference can then be used to access the objects of the vlc plugin.
<!DOCTYPE html>
<html>
<title>VLC Mozilla plugin test page</title>
<body>
<embed type="application/x-vlc-plugin" pluginspage="http://www.videolan.org"
width="640"
height="480"
id="vlc" />
<script type="text/javascript"><!--
var vlc = document.getElementById("vlc");
vlc.audio.toggleMute();
//--></script>
</body>
</html>Root object
readonly properties
- VersionInfo: returns version information string
read/write properties
- none
methods
- vlc.versionInfo(): (in vlc version < 2.2.0 only for Mozilla) returns version information string (same as VersionInfo)
- vlc.addEventListener(eventname, callback, bubble): (only for Mozilla) add a listener for mentioned event name, callback expects a function and bubble influences the order of eventhandling by JS (usually it is set to false).
- vlc.removeEventListener(eventname, callback, bubble): (only for Mozilla) remove listener for mentioned event name, callback expects a function and bubble influences the order of eventhandling by JS (usually it is set to false).
- vlc.attachEvent(eventname, callback): (only for ActiveX) add listener for mentioned event name, callback expects a function
- vlc.detachEvent(eventname, callback): (only for ActiveX) remove listener for mentioned event name, callback expects a function
events
- MediaPlayerNothingSpecial: vlc is in idle state doing nothing but waiting for a command to be issued
- MediaPlayerOpening: vlc is opening an media resource locator (MRL)
- MediaPlayerBuffering: vlc is buffering
- MediaPlayerPlaying: vlc is playing a media
- MediaPlayerPaused: vlc is in paused state
- MediaPlayerStopped: vlc is in stopped state
- MediaPlayerForward: vlc is fastforwarding through the media (works only when an input supports forward playback)
- MediaPlayerBackward: vlc is going backwards through the media (works only when an input supports backwards playback)
- MediaPlayerEncounteredError: vlc has encountered an error and is unable to continue
- MediaPlayerEndReached: vlc has reached the end of current playlist
- MediaPlayerTimeChanged: time has changed
- MediaPlayerPositionChanged: media position has changed
- MediaPlayerSeekableChanged: media seekable flag has changed (true means media is seekable, false means it is not)
- MediaPlayerPausableChanged: media pausable flag has changed (true means media is pauseable, false means it is not)
- MediaPlayerMediaChanged: (supported vlc version >= 2.2.0) media has changed
- MediaPlayerTitleChanged: (in vlc version < 2.2.0 only for Mozilla) title has changed
- MediaPlayerLengthChanged: (in vlc version < 2.2.0 only for Mozilla) length has changed
Example
The following code snippet provides easy functions to register and unregister event callbacks on all supported platforms (currently only Linux mozilla based browsers and windows activeX objects for Internet Explorer).
<script type="text/javascript"><!--
function registerVLCEvent(event, handler) {
var vlc = getVLC("vlc");
if (vlc) {
if (vlc.attachEvent) {
// Microsoft
vlc.attachEvent (event, handler);
} else if (vlc.addEventListener) {
// Mozilla: DOM level 2
vlc.addEventListener (event, handler, false);
} else {
// DOM level 0
vlc["on" + event] = handler;
}
}
// stop listening to event
function unregisterVLCEvent(event, handler) {
var vlc = getVLC("vlc");
if (vlc) {
if (vlc.detachEvent) {
// Microsoft
vlc.detachEvent (event, handler);
} else if (vlc.removeEventListener) {
// Mozilla: DOM level 2
vlc.removeEventListener (event, handler, false);
} else {
// DOM level 0
vlc["on" + event] = null;
}
}
// event callback function for testing
function handleEvents(event) {
if (!event)
event = window.event; // IE
if (event.target) {
// Netscape based browser
targ = event.target;
} else if (event.srcElement) {
// ActiveX
targ = event.srcElement;
} else {
// No event object, just the value
alert("Event value" + event );
return;
}
if (targ.nodeType == 3) // defeat Safari bug
targ = targ.parentNode;
alert("Event " + event.type + " has fired from " + targ );
}
// handle mouse grab event from video filter
function handleMouseGrab(event,X,Y) {
if (!event)
event = window.event; // IE
alert("new position (" + X + "," + Y + ")");
}
// Register a bunch of callbacks.
registerVLCEvent('MediaPlayerNothingSpecial', handleEvents);
registerVLCEvent('MediaPlayerOpening', handleEvents);
registerVLCEvent('MediaPlayerBuffering', handleEvents);
registerVLCEvent('MediaPlayerPlaying', handleEvents);
registerVLCEvent('MediaPlayerPaused', handleEvents);
registerVLCEvent('MediaPlayerStopped', handleEvents);
registerVLCEvent('MediaPlayerForward', handleEvents);
registerVLCEvent('MediaPlayerBackward', handleEvents);
registerVLCEvent('MediaPlayerEncounteredError', handleEvents);
registerVLCEvent('MediaPlayerEndReached', handleEvents);
registerVLCEvent('MediaPlayerTimeChanged', handleEvents);
registerVLCEvent('MediaPlayerPositionChanged', handleEvents);
registerVLCEvent('MediaPlayerSeekableChanged', handleEvents);
registerVLCEvent('MediaPlayerPausableChanged', handleEvents);
registerVLCEvent('MediaPlayerMediaChanged', handleEvents);
registerVLCEvent('MediaPlayerTitleChanged', handleEvents);
registerVLCEvent('MediaPlayerLengthChanged', handleEvents);
//--></script>Audio object
readonly properties
- vlc.audio.count: (supported in vlc version >= 1.1.0) returns the number of audio track available.
read/write properties
- vlc.audio.mute: boolean value to mute and unmute the audio.
- vlc.audio.volume: a value between [0-200] which indicates a percentage of the volume.
- vlc.audio.track: (supported in vlc version > 0.8.6) a value between [1-65535] which indicates the audio track to play or that is playing. a value of 0 means the audio is/will be disabled.
- vlc.audio.channel: (supported in vlc version > 0.8.6) integer value between [1-5] that indicates which audio channel mode is used, values can be: "1=stereo", "2=reverse stereo", "3=left", "4=right", "5=dolby". Use vlc.audio.channel to check if setting of the audio channel mode has succeeded.
methods
- vlc.audio.toggleMute(): boolean toggle that mutes and unmutes the audio based upon the previous state.
- vlc.audio.description(int i): (supported in vlc version >= 1.1.0) give the i-th audio track name. 0 corresponds to disable and 1 to the first audio track.
Example
Audio Channel:
<select readonly onChange='doAudioChannel(this.value)'>
<option value=1>Stereo</option>
<option value=2>Reverse stereo</option>
<option value=3>Left</option>
<option value=4>Right</option>
<option value=5>Dolby</option>
</select>
<script type="text/javascript">
<!--
function doAudioChannel(value)
{
var vlc = getVLC("vlc");
vlc.audio.channel = parseInt(value);
alert(vlc.audio.channel);
};
//-->
</script>Input object
readonly properties
- vlc.input.length: length of the input file in number of milliseconds. 0 is returned for 'live' streams or clips whose length cannot be determined by VLC. It returns -1 if no input is playing.
- vlc.input.fps: frames per second returned as a float (typically 60.0, 50.0, 23.976, etc...)
- vlc.input.hasVout: a boolean that returns true when the video is being displayed, it returns false when video is not displayed
read/write properties
- vlc.input.position: normalized position in multimedia stream item given as a float value between [0.0 - 1.0]
- vlc.input.time: the absolute position in time given in milliseconds, this property can be used to seek through the stream
<!-- absolute seek in stream !--> vlc.input.time = <absolute seek> <!-- relative seek in stream !--> vlc.input.time = vlc.input.time + <relative seek>
- vlc.input.state: current state of the input chain given as enumeration:
| 0 | IDLE |
| 1 | OPENING |
| 2 | BUFFERING |
| 3 | PLAYING |
| 4 | PAUSED |
| 5 | STOPPING |
| 6 | ENDED |
| 7 | ERROR |
Note: Test for ENDED=6 to catch end of playback. Checking for STOPPING=5 is NOT ENOUGH.
- vlc.input.rate: input speed given as float (1.0 for normal speed, 0.5 for half speed, 2.0 for twice as fast, etc.).
rate > 1 : is fastforward rate > 0 and rate < 1 : is slow motion rate < 0 : is rewind
methods
- none
Playlist object
readonly properties
- vlc.playlist.itemCount: number that returns the amount of items currently in the playlist (deprecated, do not use, see Playlist items)
- vlc.playlist.isPlaying: a boolean that returns true if the current playlist item is playing and false when it is not playing
- vlc.playlist.currentItem: (supported in vlc version >= 2.2.0) number that returns the index of the current item in the playlist. It returns -1 if the playlist is empty or no item is active.
- vlc.playlist.items: return the playlist items collection, see Playlist items
read/write properties
- none
methods
- vlc.playlist.add(mrl): add a playlist item as MRL. The MRL must be given as a string. Returns a number as an item identifier in playlist (this is not a position in playlist).
- vlc.playlist.add(mrl,name,options): add a playlist item as MRL, with metaname 'name' and options 'options'. options are text arguments which can be provided either as a single string containing space separated values, akin to VLC command line, or as an array of string values. Returns a number as an item identifier in playlist (this is not a position in playlist).
var options = new Array(":aspect-ratio=4:3", "--rtsp-tcp");
var id = vlc.playlist.add("rtsp://servername/item/to/play", "fancy name", options);
vlc.playlist.playItem(id);- vlc.playlist.play(): start playing the current playlist item
- vlc.playlist.playItem(number): start playing the item whose identifier is number
- vlc.playlist.pause(): pause the current playlist item
- vlc.playlist.togglePause(): toggle the pause state for the current playlist item
- vlc.playlist.stop(): stop playing the current playlist item
- vlc.playlist.next(): iterate to the next playlist item
- vlc.playlist.prev(): iterate to the previous playlist item
- vlc.playlist.clear(): empty the current playlist, all items will be deleted from the playlist (deprecated, do not use, see Playlist items)
- vlc.playlist.removeItem(number): remove the item from playlist whose identifier is number (deprecated, do not use, see Playlist items)
Playlist items object
readonly properties
- vlc.playlist.items.count: number of items currently in the playlist
read/write properties
- none
methods
- vlc.playlist.items.clear(): empty the current playlist, all items will be deleted from the playlist. If a movie is playing, it stop. Note that when this method returns, playlist may not have been entirely been cleared as this operation is performed asynchronously; use the count property to verify/wait until the playlist is empty.
- vlc.playlist.items.remove(number): remove the item whose identifier is number from playlist. (note: this number isn't the position in the playlist, but the number given by vlc.playlist.add() )
Subtitle object
readonly properties
- vlc.subtitle.count: (supported in vlc version >= 1.1.0) returns the number of subtitle available.
read/write properties
- vlc.subtitle.track: (supported in vlc version >= 1.1.0) get and set the subtitle track to show on the video screen. The property takes an integer as input value [1..65535]. If subtitle track is set to 0, the subtitles will be disabled. If set to a value outside the current subtitle tracks range, then it will return -1 and display an error message.
methods
- vlc.subtitle.description(int i): (supported in vlc version >= 1.1.0) give the i-th subtitle name. 0 correspond to disable and 1 to the first subtitle.
Video object
readonly properties
- vlc.video.width: returns the horizontal size of the video
- vlc.video.height: returns the vertical size of the video
read/write properties
- vlc.video.fullscreen: when set to true the video will be displayed in fullscreen mode, when set to false the video will be shown inside the video output size. The property takes a boolean as input.
- vlc.video.aspectRatio: get and set the aspect ratio to use in the video screen. The property takes a string as input value. Typical values are: "1:1", "4:3", "16:9", "16:10", "221:100" and "5:4"
- vlc.video.subtitle: (supported in vlc version > 0.8.6a) get and set the subtitle track to show on the video screen. The property takes an integer as input value [1..65535]. If subtitle track is set to 0, the subtitles will be disabled. If set to a value outside the current subtitle tracks range, then it will return -1 and display an error message.
- vlc.video.teletext: (supported in vlc version >= 0.9.0) get and set teletext page to show on the video stream. This will only work if a teletext elementary stream is available in the video stream. The property takes an integer as input value [0..999] for indicating the teletext page to view, setting the value to 0 means hide teletext. On error it will return -1 and display an error message.
methods
- vlc.video.toggleFullscreen(): toggle the fullscreen mode based on the previous setting
- vlc.video.toggleTeletext(): (supported in vlc version >= 0.9.0) toggle the teletext page to overlay transparent or not, based on the previous setting
Deinterlace Object
readonly properties
- none
read/write properties
- none
methods
- vlc.video.deinterlace.enable("my_mode"): (supported in vlc version >= 1.1.0) enable deinterlacing with my_mode. You can enable it with "blend", "bob", "discard", "linear", "mean", "x", "yadif" or "yadif2x" mode. Enabling too soon deinterlacing may cause some problems. You have to wait that all variable are available before enabling it.
- vlc.video.deinterlace.disable(): (supported in vlc version >= 1.1.0) disable deinterlacing.
Marquee Object
readonly properties
- none
read/write properties
- vlc.video.marquee.text: (supported in vlc version >= 1.1.0) display my text on the screen.
- vlc.video.marquee.color: (supported in vlc version >= 1.1.0) change the text color. val is the new color to use (WHITE=0x000000, BLACK=0xFFFFFF, RED=0xFF0000, GREEN=0x00FF00, BLUE=0x0000FF...).
- vlc.video.marquee.opacity: (supported in vlc version >= 1.1.0) change the text opacity, val is defined from 0 (completely transparent) to 255 (completely opaque).
- vlc.video.marquee.position: (supported in vlc version >= 1.1.0) change the text position (CENTER=0, LEFT=1, RIGHT=2, TOP=4, TOP-LEFT=5, TOP-RIGHT=6, BOTTOM=8, BOTTOM-LEFT=9, BOTTOM_RIGHT=10).
- vlc.video.marquee.refresh: (supported in vlc version >= 1.1.0) change the marquee refresh period.
- vlc.video.marquee.size: (supported in vlc version >= 1.1.0) val define the new size for the text displayed on the screen. If the text is bigger than the screen then the text is not displayed.
- vlc.video.marquee.timeout: (supported in vlc version >= 1.1.0) change the timeout value. val is defined in ms, but 0 value correspond to unlimited.
- vlc.video.marquee.x: (supported in vlc version >= 1.1.0) change text abscissa.
- vlc.video.marquee.y: (supported in vlc version >= 1.1.0) change text ordinate.
methods
- vlc.video.marquee.enable(): (supported in vlc version >= 1.1.0) enable marquee filter.
- vlc.video.marquee.disable(): (supported in vlc version >= 1.1.0) disable marquee filter.
Some problems may happen (option like color or text will not be applied) because of the VLC asynchronous functioning. To avoid it, after enabling marquee, you have to wait a little time before changing an option. But it should be fixed by the new vout implementation.
NOTE: [1]
Logo Object
readonly properties
- none
read/write properties
- vlc.video.logo.opacity: (supported in vlc version >= 1.1.0) change the picture opacity, val is defined from 0 (completely transparent) to 255 (completely opaque).
- vlc.video.logo.position: (supported in vlc version >= 1.1.0) change the text position ("center", "left", "right", "top", "top-left", "top-right", "bottom", "bottom-left", "bottom-right").
- vlc.video.logo.delay: (supported in vlc version >= 1.1.0) display each picture for a duration of 1000 ms (default) before displaying the next picture.
- vlc.video.logo.repeat: (supported in vlc version >= 1.1.0) number of loops for picture animation (-1=continuous, 0=disabled, n=n-times). The default is -1 (continuous).
- vlc.video.logo.x: (supported in vlc version >= 1.1.0) change the x-offset for displaying the picture counting from top-left on the screen.
- vlc.video.logo.y: (supported in vlc version >= 1.1.0) change the y-offset for displaying the picture counting from top-left on the screen.
- vlc.video.logo.width: (supported in vlc version >= 1.1.0) change the picture width.
- vlc.video.logo.height: (supported in vlc version >= 1.1.0) change the picture height.
methods
- vlc.video.logo.enable(): (supported in vlc version >= 1.1.0) enable logo video filter.
- vlc.video.logo.disable(): (supported in vlc version >= 1.1.0) disable logo video filter.
- vlc.video.logo.file("file.png"): (supported in vlc version >= 1.1.0) display my file.png as logo on the screen.
Some problems may happen because of the VLC asynchronous functioning. To avoid it, after enabling logo video filter, you have to wait a little time before changing an option. But it should be fixed by the new vout implementation.
MediaDescription Object
readonly properties
- vlc.mediaDescription.title: (supported in vlc version >= 2.0.2) returns title meta information field.
- vlc.mediaDescription.artist: (supported in vlc version >= 2.0.2) returns artist meta information field.
- vlc.mediaDescription.copyright: (supported in vlc version >= 2.0.2) returns copyright meta information field.
- vlc.mediaDescription.album: (supported in vlc version >= 2.0.2) returns album meta information field.
- vlc.mediaDescription.trackNumber: (supported in vlc version >= 2.0.2) returns trackNumber meta information field.
- vlc.mediaDescription.description: (supported in vlc version >= 2.0.2) returns description meta information field.
- vlc.mediaDescription.rating: (supported in vlc version >= 2.0.2) returns rating meta information field.
- vlc.mediaDescription.date: (supported in vlc version >= 2.0.2) returns date meta information field.
- vlc.mediaDescription.setting: (supported in vlc version >= 2.0.2) returns setting meta information field.
- vlc.mediaDescription.URL: (supported in vlc version >= 2.0.2) returns URL meta information field.
- vlc.mediaDescription.language: (supported in vlc version >= 2.0.2) returns language meta information field.
- vlc.mediaDescription.nowPlaying: (supported in vlc version >= 2.0.2) returns nowPlaying meta information field.
- vlc.mediaDescription.publisher: (supported in vlc version >= 2.0.2) returns publisher meta information field.
- vlc.mediaDescription.encodedBy: (supported in vlc version >= 2.0.2) returns encodedBy meta information field.
- vlc.mediaDescription.artworkURL: (supported in vlc version >= 2.0.2) returns artworkURL meta information field.
- vlc.mediaDescription.trackID: (supported in vlc version >= 2.0.2) returns trackID meta information field.
read/write properties
- none
methods
- none
DEPRECATED APIs
DEPRECATED: Log object
- CAUTION: For security concern, VLC 1.0.0-rc1 is the latest (near-to-stable) version in which this object and its children are supported.
This object allows accessing VLC main message logging queue. Typically this queue capacity is very small (no nore than 256 entries) and can easily overflow, therefore messages should be read and cleared as often as possible.
readonly properties
- vlc.log.messages: returns the message collection, see Messages object
read/write properties
- vlc.log.verbosity: write number [-1,0,1,2,3] for changing the verbosity level of the log messages; messages whose verbosity is higher than set will be not be logged in the queue. The numbers have the following meaning: -1 disable, 0 info, 1 error, 2 warning, 3 debug.
methods
- none
DEPRECATED: Messages object
- CAUTION: For security concern, VLC 1.0.0-rc1 is the latest (near-to-stable) version in which this object and its children are supported.
readonly properties
- messages.count: returns number of messages in the log
read/write properties
- none
methods
- messages.clear(): clear the current log buffer. It should be called as frequently as possible to not overflow the message queue. Call this method after the log messages of interest are read.
- messages.iterator(): creates and returns an iterator object, used to iterate over the messages in the log. Don't clear the log buffer while holding an iterator object.
DEPRECATED: Messages Iterator object
- CAUTION: For security concern, VLC 1.0.0-rc1 is the latest (near-to-stable) version in which this object and its children are supported.
readonly properties
- iterator.hasNext: returns a boolean that indicates whether vlc.log.messages.next() will return the next message.
read/write properties
- none
methods
- iterator.next(): returns the next message object in the log, see Message object
DEPRECATED: Message subobject
- CAUTION: For security concern, VLC 1.0.0-rc1 is the latest (near-to-stable) version in which this object and its children are supported.
- message.severity: number that indicates the severity of the log message (0 = info, 1 = error, 2 = warning, 3 = debug)
- message.name: name of VLC module that printed the log message (e.g: main, http, directx, etc...)
- message.type: type of VLC module that printed the log message (eg: input, access, vout, sout, etc...)
- message.message: the message text
This page is part of official VLC media player Documentation (User Guide • Streaming HowTo • Hacker Guide • Modules)
Please read the Documentation Editing Guidelines before you edit the documentation
Please read the Documentation Editing Guidelines before you edit the documentation
Permission is granted to copy, distribute and/or modify this document under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.
