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diff --git a/ffmpeg/doc/ffserver.texi b/ffmpeg/doc/ffserver.texi index f1b7599..ed538c1 100644 --- a/ffmpeg/doc/ffserver.texi +++ b/ffmpeg/doc/ffserver.texi @@ -16,11 +16,14 @@ ffserver [@var{options}] @chapter Description @c man begin DESCRIPTION -@command{ffserver} is a streaming server for both audio and video. It -supports several live feeds, streaming from files and time shifting on -live feeds (you can seek to positions in the past on each live feed, -provided you specify a big enough feed storage in -@file{ffserver.conf}). +@command{ffserver} is a streaming server for both audio and video. +It supports several live feeds, streaming from files and time shifting +on live feeds. You can seek to positions in the past on each live +feed, provided you specify a big enough feed storage. + +@command{ffserver} is configured through a configuration file, which +is read at startup. If not explicitly specified, it will read from +@file{/etc/ffserver.conf}. @command{ffserver} receives prerecorded files or FFM streams from some @command{ffmpeg} instance as input, then streams them over @@ -39,10 +42,118 @@ For each feed you can have different output streams in various formats, each one specified by a @code{<Stream>} section in the configuration file. +@chapter Detailed description + +@command{ffserver} works by forwarding streams encoded by +@command{ffmpeg}, or pre-recorded streams which are read from disk. + +Precisely, @command{ffserver} acts as an HTTP server, accepting POST +requests from @command{ffmpeg} to acquire the stream to publish, and +serving HTTP clients GET requests with the stream media content. + +A feed is an @ref{FFM} stream created by @command{ffmpeg}, and sent to +a port where @command{ffserver} is listening. + +Each feed is identified by a unique name, corresponding to the name +of the resource published on @command{ffserver}, and is configured by +a dedicated @code{Feed} section in the configuration file. + +The feed publish URL is given by: +@example +http://@var{ffserver_ip_address}:@var{http_port}/@var{feed_name} +@end example + +where @var{ffserver_ip_address} is the IP address of the machine where +@command{ffserver} is installed, @var{http_port} is the port number of +the HTTP server (configured through the @option{Port} option), and +@var{feed_name} is the name of the corresponding feed defined in the +configuration file. + +Each feed is associated to a file which is stored on disk. This stored +file is used to allow to send pre-recorded data to a player as fast as +possible when new content is added in real-time to the stream. + +A "live-stream" or "stream" is a resource published by +@command{ffserver}, and made accessible through the HTTP protocol to +clients. + +A stream can be connected to a feed, or to a file. In the first case, +the published stream is forwarded from the corresponding feed +generated by a running instance of @command{ffmpeg}, in the second +case the stream is read from a pre-recorded file. + +Each stream is identified by a unique name, corresponding to the name +of the resource served by @command{ffserver}, and is configured by +a dedicated @code{Stream} section in the configuration file. + +The stream access URL is given by: +@example +http://@var{ffserver_ip_address}:@var{http_port}/@var{stream_name}[@var{options}] +@end example + +@var{stream_name} is the name of the corresponding stream defined in +the configuration file. @var{options} is a list of options specified +after the URL which affects how the stream is served by +@command{ffserver}. + +In case the stream is associated to a feed, the encoding parameters +must be configured in the stream configuration. They are sent to +@command{ffmpeg} when setting up the encoding. This allows +@command{ffserver} to define the encoding parameters used by +the @command{ffmpeg} encoders. + +The @command{ffmpeg} @option{override_ffserver} commandline option +allows to override the encoding parameters set by the server. + +Multiple streams can be connected to the same feed. + +For example, you can have a situation described by the following +graph: +@example + _________ __________ + | | | | +ffmpeg 1 -----| feed 1 |-----| stream 1 | + \ |_________|\ |__________| + \ \ + \ \ __________ + \ \ | | + \ \| stream 2 | + \ |__________| + \ + \ _________ __________ + \ | | | | + \| feed 2 |-----| stream 3 | + |_________| |__________| + + _________ __________ + | | | | +ffmpeg 2 -----| feed 3 |-----| stream 4 | + |_________| |__________| + + _________ __________ + | | | | + | file 1 |-----| stream 5 | + |_________| |__________| +@end example + +@anchor{FFM} +@section FFM, FFM2 formats + +FFM and FFM2 are formats used by ffserver. They allow storing a wide variety of +video and audio streams and encoding options, and can store a moving time segment +of an infinite movie or a whole movie. + +FFM is version specific, and there is limited compatibility of FFM files +generated by one version of ffmpeg/ffserver and another version of +ffmpeg/ffserver. It may work but it is not guaranteed to work. + +FFM2 is extensible while maintaining compatibility and should work between +differing versions of tools. FFM2 is the default. + @section Status stream -ffserver supports an HTTP interface which exposes the current status -of the server. +@command{ffserver} supports an HTTP interface which exposes the +current status of the server. Simply point your browser to the address of the special status stream specified in the configuration file. @@ -61,27 +172,8 @@ ACL allow 192.168.0.0 192.168.255.255 then the server will post a page with the status information when the special stream @file{status.html} is requested. -@section What can this do? - -When properly configured and running, you can capture video and audio in real -time from a suitable capture card, and stream it out over the Internet to -either Windows Media Player or RealAudio player (with some restrictions). - -It can also stream from files, though that is currently broken. Very often, a -web server can be used to serve up the files just as well. - -It can stream prerecorded video from .ffm files, though it is somewhat tricky -to make it work correctly. - @section How do I make it work? -First, build the kit. It *really* helps to have installed LAME first. Then when -you run the ffserver ./configure, make sure that you have the -@code{--enable-libmp3lame} flag turned on. - -LAME is important as it allows for streaming audio to Windows Media Player. -Don't ask why the other audio types do not work. - As a simple test, just run the following two command lines where INPUTFILE is some file which you can decode with ffmpeg: @@ -109,35 +201,6 @@ You should edit the ffserver.conf file to suit your needs (in terms of frame rates etc). Then install ffserver and ffmpeg, write a script to start them up, and off you go. -@section Troubleshooting - -@subsection I don't hear any audio, but video is fine. - -Maybe you didn't install LAME, or got your ./configure statement wrong. Check -the ffmpeg output to see if a line referring to MP3 is present. If not, then -your configuration was incorrect. If it is, then maybe your wiring is not -set up correctly. Maybe the sound card is not getting data from the right -input source. Maybe you have a really awful audio interface (like I do) -that only captures in stereo and also requires that one channel be flipped. -If you are one of these people, then export 'AUDIO_FLIP_LEFT=1' before -starting ffmpeg. - -@subsection The audio and video lose sync after a while. - -Yes, they do. - -@subsection After a long while, the video update rate goes way down in WMP. - -Yes, it does. Who knows why? - -@subsection WMP 6.4 behaves differently to WMP 7. - -Yes, it does. Any thoughts on this would be gratefully received. These -differences extend to embedding WMP into a web page. [There are two -object IDs that you can use: The old one, which does not play well, and -the new one, which does (both tested on the same system). However, -I suspect that the new one is not available unless you have installed WMP 7]. - @section What else can it do? You can replay video from .ffm files that was recorded earlier. @@ -177,9 +240,6 @@ specify a time. In addition, ffserver will skip frames until a key_frame is found. This further reduces the startup delay by not transferring data that will be discarded. -* You may want to adjust the MaxBandwidth in the ffserver.conf to limit -the amount of bandwidth consumed by live streams. - @section Why does the ?buffer / Preroll stop working after a time? It turns out that (on my machine at least) the number of frames successfully @@ -213,43 +273,588 @@ You use this by adding the ?date= to the end of the URL for the stream. For example: @samp{http://localhost:8080/test.asf?date=2002-07-26T23:05:00}. @c man end -@section What is FFM, FFM2 - -FFM and FFM2 are formats used by ffserver. They allow storing a wide variety of -video and audio streams and encoding options, and can store a moving time segment -of an infinite movie or a whole movie. - -FFM is version specific, and there is limited compatibility of FFM files -generated by one version of ffmpeg/ffserver and another version of -ffmpeg/ffserver. It may work but it is not guaranteed to work. - -FFM2 is extensible while maintaining compatibility and should work between -differing versions of tools. FFM2 is the default. - @chapter Options @c man begin OPTIONS -@include avtools-common-opts.texi +@include fftools-common-opts.texi @section Main options @table @option @item -f @var{configfile} -Use @file{configfile} instead of @file{/etc/ffserver.conf}. +Read configuration file @file{configfile}. If not specified it will +read by default from @file{/etc/ffserver.conf}. + @item -n -Enable no-launch mode. This option disables all the Launch directives -within the various <Stream> sections. Since ffserver will not launch -any ffmpeg instances, you will have to launch them manually. +Enable no-launch mode. This option disables all the @code{Launch} +directives within the various @code{<Feed>} sections. Since +@command{ffserver} will not launch any @command{ffmpeg} instances, you +will have to launch them manually. + @item -d -Enable debug mode. This option increases log verbosity, directs log -messages to stdout. +Enable debug mode. This option increases log verbosity, and directs +log messages to stdout. When specified, the @option{CustomLog} option +is ignored. +@end table + +@chapter Configuration file syntax + +@command{ffserver} reads a configuration file containing global +options and settings for each stream and feed. + +The configuration file consists of global options and dedicated +sections, which must be introduced by "<@var{SECTION_NAME} +@var{ARGS}>" on a separate line and must be terminated by a line in +the form "</@var{SECTION_NAME}>". @var{ARGS} is optional. + +Currently the following sections are recognized: @samp{Feed}, +@samp{Stream}, @samp{Redirect}. + +A line starting with @code{#} is ignored and treated as a comment. + +Name of options and sections are case-insensitive. + +@section ACL syntax +An ACL (Access Control List) specifies the address which are allowed +to access a given stream, or to write a given feed. + +It accepts the folling forms +@itemize +@item +Allow/deny access to @var{address}. +@example +ACL ALLOW <address> +ACL DENY <address> +@end example + +@item +Allow/deny access to ranges of addresses from @var{first_address} to +@var{last_address}. +@example +ACL ALLOW <first_address> <last_address> +ACL DENY <first_address> <last_address> +@end example +@end itemize + +You can repeat the ACL allow/deny as often as you like. It is on a per +stream basis. The first match defines the action. If there are no matches, +then the default is the inverse of the last ACL statement. + +Thus 'ACL allow localhost' only allows access from localhost. +'ACL deny 1.0.0.0 1.255.255.255' would deny the whole of network 1 and +allow everybody else. + +@section Global options +@table @option +@item Port @var{port_number} +@item RTSPPort @var{port_number} + +Set TCP port number on which the HTTP/RTSP server is listening. You +must select a different port from your standard HTTP web server if it +is running on the same computer. + +If not specified, no corresponding server will be created. + +@item BindAddress @var{ip_address} +@item RTSPBindAddress @var{ip_address} +Set address on which the HTTP/RTSP server is bound. Only useful if you +have several network interfaces. + +@item MaxHTTPConnections @var{n} +Set number of simultaneous HTTP connections that can be handled. It +has to be defined @emph{before} the @option{MaxClients} parameter, +since it defines the @option{MaxClients} maximum limit. + +Default value is 2000. + +@item MaxClients @var{n} +Set number of simultaneous requests that can be handled. Since +@command{ffserver} is very fast, it is more likely that you will want +to leave this high and use @option{MaxBandwidth}. + +Default value is 5. + +@item MaxBandwidth @var{kbps} +Set the maximum amount of kbit/sec that you are prepared to consume +when streaming to clients. + +Default value is 1000. + +@item CustomLog @var{filename} +Set access log file (uses standard Apache log file format). '-' is the +standard output. + +If not specified @command{ffserver} will produce no log. + +In case the commandline option @option{-d} is specified this option is +ignored, and the log is written to standard output. + +@item NoDaemon +Set no-daemon mode. This option is currently ignored since now +@command{ffserver} will always work in no-daemon mode, and is +deprecated. +@end table + +@section Feed section + +A Feed section defines a feed provided to @command{ffserver}. + +Each live feed contains one video and/or audio sequence coming from an +@command{ffmpeg} encoder or another @command{ffserver}. This sequence +may be encoded simultaneously with several codecs at several +resolutions. + +A feed instance specification is introduced by a line in the form: +@example +<Feed FEED_FILENAME> +@end example + +where @var{FEED_FILENAME} specifies the unique name of the FFM stream. + +The following options are recognized within a Feed section. + +@table @option +@item File @var{filename} +@item ReadOnlyFile @var{filename} +Set the path where the feed file is stored on disk. + +If not specified, the @file{/tmp/FEED.ffm} is assumed, where +@var{FEED} is the feed name. + +If @option{ReadOnlyFile} is used the file is marked as read-only and +it will not be deleted or updated. + +@item Truncate +Truncate the feed file, rather than appending to it. By default +@command{ffserver} will append data to the file, until the maximum +file size value is reached (see @option{FileMaxSize} option). + +@item FileMaxSize @var{size} +Set maximum size of the feed file in bytes. 0 means unlimited. The +postfixes @code{K} (2^10), @code{M} (2^20), and @code{G} (2^30) are +recognized. + +Default value is 5M. + +@item Launch @var{args} +Launch an @command{ffmpeg} command when creating @command{ffserver}. + +@var{args} must be a sequence of arguments to be provided to an +@command{ffmpeg} instance. The first provided argument is ignored, and +it is replaced by a path with the same dirname of the @command{ffserver} +instance, followed by the remaining argument and terminated with a +path corresponding to the feed. + +When the launched process exits, @command{ffserver} will launch +another program instance. + +In case you need a more complex @command{ffmpeg} configuration, +e.g. if you need to generate multiple FFM feeds with a single +@command{ffmpeg} instance, you should launch @command{ffmpeg} by hand. + +This option is ignored in case the commandline option @option{-n} is +specified. + +@item ACL @var{spec} +Specify the list of IP address which are allowed or denied to write +the feed. Multiple ACL options can be specified. @end table + +@section Stream section + +A Stream section defines a stream provided by @command{ffserver}, and +identified by a single name. + +The stream is sent when answering a request containing the stream +name. + +A stream section must be introduced by the line: +@example +<Stream STREAM_NAME> +@end example + +where @var{STREAM_NAME} specifies the unique name of the stream. + +The following options are recognized within a Stream section. + +Encoding options are marked with the @emph{encoding} tag, and they are +used to set the encoding parameters, and are mapped to libavcodec +encoding options. Not all encoding options are supported, in +particular it is not possible to set encoder private options. In order +to override the encoding options specified by @command{ffserver}, you +can use the @command{ffmpeg} @option{override_ffserver} commandline +option. + +Only one of the @option{Feed} and @option{File} options should be set. + +@table @option +@item Feed @var{feed_name} +Set the input feed. @var{feed_name} must correspond to an existing +feed defined in a @code{Feed} section. + +When this option is set, encoding options are used to setup the +encoding operated by the remote @command{ffmpeg} process. + +@item File @var{filename} +Set the filename of the pre-recorded input file to stream. + +When this option is set, encoding options are ignored and the input +file content is re-streamed as is. + +@item Format @var{format_name} +Set the format of the output stream. + +Must be the name of a format recognized by FFmpeg. If set to +@samp{status}, it is treated as a status stream. + +@item InputFormat @var{format_name} +Set input format. If not specified, it is automatically guessed. + +@item Preroll @var{n} +Set this to the number of seconds backwards in time to start. Note that +most players will buffer 5-10 seconds of video, and also you need to allow +for a keyframe to appear in the data stream. + +Default value is 0. + +@item StartSendOnKey +Do not send stream until it gets the first key frame. By default +@command{ffserver} will send data immediately. + +@item MaxTime @var{n} +Set the number of seconds to run. This value set the maximum duration +of the stream a client will be able to receive. + +A value of 0 means that no limit is set on the stream duration. + +@item ACL @var{spec} +Set ACL for the stream. + +@item DynamicACL @var{spec} + +@item RTSPOption @var{option} + +@item MulticastAddress @var{address} + +@item MulticastPort @var{port} + +@item MulticastTTL @var{integer} + +@item NoLoop + +@item FaviconURL @var{url} +Set favicon (favourite icon) for the server status page. It is ignored +for regular streams. + +@item Author @var{value} +@item Comment @var{value} +@item Copyright @var{value} +@item Title @var{value} +Set metadata corresponding to the option. All these options are +deprecated in favor of @option{Metadata}. + +@item Metadata @var{key} @var{value} +Set metadata value on the output stream. + +@item NoAudio +@item NoVideo +Suppress audio/video. + +@item AudioCodec @var{codec_name} (@emph{encoding,audio}) +Set audio codec. + +@item AudioBitRate @var{rate} (@emph{encoding,audio}) +Set bitrate for the audio stream in kbits per second. + +@item AudioChannels @var{n} (@emph{encoding,audio}) +Set number of audio channels. + +@item AudioSampleRate @var{n} (@emph{encoding,audio}) +Set sampling frequency for audio. When using low bitrates, you should +lower this frequency to 22050 or 11025. The supported frequencies +depend on the selected audio codec. + +@item AVOptionAudio @var{option} @var{value} (@emph{encoding,audio}) +Set generic option for audio stream. + +@item AVPresetAudio @var{preset} (@emph{encoding,audio}) +Set preset for audio stream. + +@item VideoCodec @var{codec_name} (@emph{encoding,video}) +Set video codec. + +@item VideoBitRate @var{n} (@emph{encoding,video}) +Set bitrate for the video stream in kbits per second. + +@item VideoBitRateRange @var{range} (@emph{encoding,video}) +Set video bitrate range. + +A range must be specified in the form @var{minrate}-@var{maxrate}, and +specifies the @option{minrate} and @option{maxrate} encoding options +expressed in kbits per second. + +@item VideoBitRateRangeTolerance @var{n} (@emph{encoding,video}) +Set video bitrate tolerance in kbits per second. + +@item PixelFormat @var{pixel_format} (@emph{encoding,video}) +Set video pixel format. + +@item Debug @var{integer} (@emph{encoding,video}) +Set video @option{debug} encoding option. + +@item Strict @var{integer} (@emph{encoding,video}) +Set video @option{strict} encoding option. + +@item VideoBufferSize @var{n} (@emph{encoding,video}) +Set ratecontrol buffer size, expressed in KB. + +@item VideoFrameRate @var{n} (@emph{encoding,video}) +Set number of video frames per second. + +@item VideoSize (@emph{encoding,video}) +Set size of the video frame, must be an abbreviation or in the form +@var{W}x@var{H}. See @ref{video size syntax,,the Video size section +in the ffmpeg-utils(1) manual,ffmpeg-utils}. + +Default value is @code{160x128}. + +@item VideoIntraOnly (@emph{encoding,video}) +Transmit only intra frames (useful for low bitrates, but kills frame rate). + +@item VideoGopSize @var{n} (@emph{encoding,video}) +If non-intra only, an intra frame is transmitted every VideoGopSize +frames. Video synchronization can only begin at an intra frame. + +@item VideoTag @var{tag} (@emph{encoding,video}) +Set video tag. + +@item VideoHighQuality (@emph{encoding,video}) +@item Video4MotionVector (@emph{encoding,video}) + +@item BitExact (@emph{encoding,video}) +Set bitexact encoding flag. + +@item IdctSimple (@emph{encoding,video}) +Set simple IDCT algorithm. + +@item Qscale @var{n} (@emph{encoding,video}) +Enable constant quality encoding, and set video qscale (quantization +scale) value, expressed in @var{n} QP units. + +@item VideoQMin @var{n} (@emph{encoding,video}) +@item VideoQMax @var{n} (@emph{encoding,video}) +Set video qmin/qmax. + +@item VideoQDiff @var{integer} (@emph{encoding,video}) +Set video @option{qdiff} encoding option. + +@item LumiMask @var{float} (@emph{encoding,video}) +@item DarkMask @var{float} (@emph{encoding,video}) +Set @option{lumi_mask}/@option{dark_mask} encoding options. + +@item AVOptionVideo @var{option} @var{value} (@emph{encoding,video}) +Set generic option for video stream. + +@item AVPresetVideo @var{preset} (@emph{encoding,video}) +Set preset for video stream. + +@var{preset} must be the path of a preset file. +@end table + +@subsection Server status stream + +A server status stream is a special stream which is used to show +statistics about the @command{ffserver} operations. + +It must be specified setting the option @option{Format} to +@samp{status}. + +@section Redirect section + +A redirect section specifies where to redirect the requested URL to +another page. + +A redirect section must be introduced by the line: +@example +<Redirect NAME> +@end example + +where @var{NAME} is the name of the page which should be redirected. + +It only accepts the option @option{URL}, which specify the redirection +URL. + +@chapter Stream examples + +@itemize +@item +Multipart JPEG +@example +<Stream test.mjpg> +Feed feed1.ffm +Format mpjpeg +VideoFrameRate 2 +VideoIntraOnly +NoAudio +Strict -1 +</Stream> +@end example + +@item +Single JPEG +@example +<Stream test.jpg> +Feed feed1.ffm +Format jpeg +VideoFrameRate 2 +VideoIntraOnly +VideoSize 352x240 +NoAudio +Strict -1 +</Stream> +@end example + +@item +Flash +@example +<Stream test.swf> +Feed feed1.ffm +Format swf +VideoFrameRate 2 +VideoIntraOnly +NoAudio +</Stream> +@end example + +@item +ASF compatible +@example +<Stream test.asf> +Feed feed1.ffm +Format asf +VideoFrameRate 15 +VideoSize 352x240 +VideoBitRate 256 +VideoBufferSize 40 +VideoGopSize 30 +AudioBitRate 64 +StartSendOnKey +</Stream> +@end example + +@item +MP3 audio +@example +<Stream test.mp3> +Feed feed1.ffm +Format mp2 +AudioCodec mp3 +AudioBitRate 64 +AudioChannels 1 +AudioSampleRate 44100 +NoVideo +</Stream> +@end example + +@item +Ogg Vorbis audio +@example +<Stream test.ogg> +Feed feed1.ffm +Metadata title "Stream title" +AudioBitRate 64 +AudioChannels 2 +AudioSampleRate 44100 +NoVideo +</Stream> +@end example + +@item +Real with audio only at 32 kbits +@example +<Stream test.ra> +Feed feed1.ffm +Format rm +AudioBitRate 32 +NoVideo +</Stream> +@end example + +@item +Real with audio and video at 64 kbits +@example +<Stream test.rm> +Feed feed1.ffm +Format rm +AudioBitRate 32 +VideoBitRate 128 +VideoFrameRate 25 +VideoGopSize 25 +</Stream> +@end example + +@item +For stream coming from a file: you only need to set the input filename +and optionally a new format. + +@example +<Stream file.rm> +File "/usr/local/httpd/htdocs/tlive.rm" +NoAudio +</Stream> +@end example + +@example +<Stream file.asf> +File "/usr/local/httpd/htdocs/test.asf" +NoAudio +Metadata author "Me" +Metadata copyright "Super MegaCorp" +Metadata title "Test stream from disk" +Metadata comment "Test comment" +</Stream> +@end example +@end itemize + @c man end +@include config.texi +@ifset config-all +@ifset config-avutil +@include utils.texi +@end ifset +@ifset config-avcodec +@include codecs.texi +@include bitstream_filters.texi +@end ifset +@ifset config-avformat +@include formats.texi +@include protocols.texi +@end ifset +@ifset config-avdevice +@include devices.texi +@end ifset +@ifset config-swresample +@include resampler.texi +@end ifset +@ifset config-swscale +@include scaler.texi +@end ifset +@ifset config-avfilter +@include filters.texi +@end ifset +@end ifset + @chapter See Also @ifhtml -The @file{doc/ffserver.conf} example, +@ifset config-all +@url{ffserver.html,ffserver}, +@end ifset +@ifset config-not-all +@url{ffserver-all.html,ffserver-all}, +@end ifset +the @file{doc/ffserver.conf} example, @url{ffmpeg.html,ffmpeg}, @url{ffplay.html,ffplay}, @url{ffprobe.html,ffprobe}, @url{ffmpeg-utils.html,ffmpeg-utils}, @url{ffmpeg-scaler.html,ffmpeg-scaler}, @@ -263,7 +868,13 @@ The @file{doc/ffserver.conf} example, @end ifhtml @ifnothtml -The @file{doc/ffserver.conf} example, ffmpeg(1), ffplay(1), ffprobe(1), +@ifset config-all +ffserver(1), +@end ifset +@ifset config-not-all +ffserver-all(1), +@end ifset +the @file{doc/ffserver.conf} example, ffmpeg(1), ffplay(1), ffprobe(1), ffmpeg-utils(1), ffmpeg-scaler(1), ffmpeg-resampler(1), ffmpeg-codecs(1), ffmpeg-bitstream-filters(1), ffmpeg-formats(1), ffmpeg-devices(1), ffmpeg-protocols(1), ffmpeg-filters(1) |