\input texinfo @c -*- texinfo -*- @settitle ffserver Documentation @titlepage @center @titlefont{ffserver Documentation} @end titlepage @top @contents @chapter Synopsis 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} receives prerecorded files or FFM streams from some @command{ffmpeg} instance as input, then streams them over RTP/RTSP/HTTP. An @command{ffserver} instance will listen on some port as specified in the configuration file. You can launch one or more instances of @command{ffmpeg} and send one or more FFM streams to the port where ffserver is expecting to receive them. Alternately, you can make @command{ffserver} launch such @command{ffmpeg} instances at startup. Input streams are called feeds, and each one is specified by a @code{} section in the configuration file. For each feed you can have different output streams in various formats, each one specified by a @code{} section in the configuration file. @section Status stream 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. For example if you have: @example Format status # Only allow local people to get the status ACL allow localhost ACL allow 192.168.0.0 192.168.255.255 @end example 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: @example ffserver -f doc/ffserver.conf & ffmpeg -i INPUTFILE http://localhost:8090/feed1.ffm @end example At this point you should be able to go to your Windows machine and fire up Windows Media Player (WMP). Go to Open URL and enter @example http://:8090/test.asf @end example You should (after a short delay) see video and hear audio. WARNING: trying to stream test1.mpg doesn't work with WMP as it tries to transfer the entire file before starting to play. The same is true of AVI files. @section What happens next? 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 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. However, there are a number of caveats, including the fact that the ffserver parameters must match the original parameters used to record the file. If they do not, then ffserver deletes the file before recording into it. (Now that I write this, it seems broken). You can fiddle with many of the codec choices and encoding parameters, and there are a bunch more parameters that you cannot control. Post a message to the mailing list if there are some 'must have' parameters. Look in ffserver.conf for a list of the currently available controls. It will automatically generate the ASX or RAM files that are often used in browsers. These files are actually redirections to the underlying ASF or RM file. The reason for this is that the browser often fetches the entire file before starting up the external viewer. The redirection files are very small and can be transferred quickly. [The stream itself is often 'infinite' and thus the browser tries to download it and never finishes.] @section Tips * When you connect to a live stream, most players (WMP, RA, etc) want to buffer a certain number of seconds of material so that they can display the signal continuously. However, ffserver (by default) starts sending data in realtime. This means that there is a pause of a few seconds while the buffering is being done by the player. The good news is that this can be cured by adding a '?buffer=5' to the end of the URL. This means that the stream should start 5 seconds in the past -- and so the first 5 seconds of the stream are sent as fast as the network will allow. It will then slow down to real time. This noticeably improves the startup experience. You can also add a 'Preroll 15' statement into the ffserver.conf that will add the 15 second prebuffering on all requests that do not otherwise 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 grabbed is marginally less than the number that ought to be grabbed. This means that the timestamp in the encoded data stream gets behind realtime. This means that if you say 'Preroll 10', then when the stream gets 10 or more seconds behind, there is no Preroll left. Fixing this requires a change in the internals of how timestamps are handled. @section Does the @code{?date=} stuff work. Yes (subject to the limitation outlined above). Also note that whenever you start ffserver, it deletes the ffm file (if any parameters have changed), thus wiping out what you had recorded before. The format of the @code{?date=xxxxxx} is fairly flexible. You should use one of the following formats (the 'T' is literal): @example * YYYY-MM-DDTHH:MM:SS (localtime) * YYYY-MM-DDTHH:MM:SSZ (UTC) @end example You can omit the YYYY-MM-DD, and then it refers to the current day. However note that @samp{?date=16:00:00} refers to 16:00 on the current day -- this may be in the future and so is unlikely to be useful. 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 fftools-common-opts.texi @section Main options @table @option @item -f @var{configfile} Use @file{configfile} instead of @file{/etc/ffserver.conf}. @item -n Enable no-launch mode. This option disables all the Launch directives within the various sections. Since ffserver will not launch any ffmpeg instances, you will have to launch them manually. @item -d Enable debug mode. This option increases log verbosity, directs log messages to stdout. @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{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. @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/RTPS 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. @end table @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
ACL DENY
@end example @item Allow/deny access to ranges of addresses from @var{first_address} to @var{last_address}. @example ACL ALLOW ACL DENY @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 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 @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} Set the path where the file is stored on disk. @item FileMaxSize @var{size} Set maximum size of the feed. 0 means unlimited. @item ReadOnlyFile @var{filename} Mark the file as readonly and it will not be deleted or updated. @item Launch @item ACL 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 @end example where @var{STREAM_NAME} specifies the unique name of the stream. The following options are recognized within a Stream section. @table @option @item Feed @var{feed_name} Set the input feed. Must be specified. @item Format @var{format_name} Set the format of the stream. Must be the name of a format recognized by FFmpeg. @item AudioBitRate @var{rate} Set bitrate for the audio stream in KB per second. @item AudioChannels @var{n} Set number of audio channels. @item AudioSampleRate @var{n} 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 VideoBitRate @var{n} Set bitrate for the video stream in KB per second. @item VideoBitRateRange @var{range} Set video bitrate range. @item VideoBitRateRangeTolerance @var{n} @item PixelFormat Set video pixel format. @item VideoBufferSize @var{n} Set ratecontrol buffer size. @item VideoFrameRate @var{n} Set number of video frames per second. @item VideoSize 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 Transmit only intra frames (useful for low bitrates, but kills frame rate). @item VideoGopSize @var{n} If non-intra only, an intra frame is transmitted every VideoGopSize frames. Video synchronization can only begin at an intra frame. @item VideoHighQuality @item Video4MotionVector @item AudioCodec @var{codec_name} @item VideoCodec @var{codec_name} Set audio/video codec. @item NoAudio @item NoVideo Suppress audio/video. @item VideoQMin @var{n} @item VideoQMax @var{n} Set video qmin/qmax. @item AVOptionAudio @var{option} @var{value} @item AVOptionVideo @var{option} @var{value} Set generic option for audio/video stream. @item AVPresetAudio @var{preset} @item AVOptionVideo @var{preset} Set preset for audio/video stream. @var{preset} must be the path of a preset file. @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. @item ACL @var{spec} Set ACL for the stream. @item Author @var{value} @item Comment @var{value} @item Copyright @var{value} @item Title @var{value} Set metadata corresponding to the option. @item StartSendOnKey Do not send stream until it gets the first key frame. By default @command{ffserver} will send data immediately. @item FaviconURL @var{url} Set favicon (favourite icon) for the server status page. It is ignored for regular streams. @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 @code{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 @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 Feed feed1.ffm Format mpjpeg VideoFrameRate 2 VideoIntraOnly NoAudio Strict -1 @end example @item Single JPEG @example Feed feed1.ffm Format jpeg VideoFrameRate 2 VideoIntraOnly #VideoSize 352x240 NoAudio Strict -1 @end example @item Flash @example Feed feed1.ffm Format swf VideoFrameRate 2 VideoIntraOnly NoAudio @end example @item ASF compatible @example Feed feed1.ffm Format asf VideoFrameRate 15 VideoSize 352x240 VideoBitRate 256 VideoBufferSize 40 VideoGopSize 30 AudioBitRate 64 StartSendOnKey @end example @item MP3 audio @example Feed feed1.ffm Format mp2 AudioCodec mp3 AudioBitRate 64 AudioChannels 1 AudioSampleRate 44100 NoVideo @end example @item Ogg Vorbis audio: @example Feed feed1.ffm Title "Stream title" AudioBitRate 64 AudioChannels 2 AudioSampleRate 44100 NoVideo @end example @item Real with audio only at 32 kbits @example Feed feed1.ffm Format rm AudioBitRate 32 NoVideo NoAudio @end example @item Real with audio and video at 64 kbits @example Feed feed1.ffm Format rm AudioBitRate 32 VideoBitRate 128 VideoFrameRate 25 VideoGopSize 25 NoAudio @end example @item For stream coming from a file: you only need to set the input filename and optionally a new format. @example File "/usr/local/httpd/htdocs/tlive.rm" NoAudio @end example @example File "/usr/local/httpd/htdocs/test.asf" NoAudio Author "Me" Copyright "Super MegaCorp" Title "Test stream from disk" Comment "Test comment" @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 @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}, @url{ffmpeg-resampler.html,ffmpeg-resampler}, @url{ffmpeg-codecs.html,ffmpeg-codecs}, @url{ffmpeg-bitstream-filters.html,ffmpeg-bitstream-filters}, @url{ffmpeg-formats.html,ffmpeg-formats}, @url{ffmpeg-devices.html,ffmpeg-devices}, @url{ffmpeg-protocols.html,ffmpeg-protocols}, @url{ffmpeg-filters.html,ffmpeg-filters} @end ifhtml @ifnothtml @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) @end ifnothtml @include authors.texi @ignore @setfilename ffserver @settitle ffserver video server @end ignore @bye