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diff --git a/doc/avserver.texi b/doc/avserver.texi deleted file mode 100644 index 88e6221..0000000 --- a/doc/avserver.texi +++ /dev/null @@ -1,276 +0,0 @@ -\input texinfo @c -*- texinfo -*- - -@settitle avserver Documentation -@titlepage -@center @titlefont{avserver Documentation} -@end titlepage - -@top - -@contents - -@chapter Synopsys - -The generic syntax is: - -@example -@c man begin SYNOPSIS -avserver [options] -@c man end -@end example - -@chapter Description -@c man begin DESCRIPTION - -WARNING: avserver is unmaintained, largely broken and in need of a -complete rewrite. It probably won't work for you. Use at your own -risk. - -avserver 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 avserver.conf). - -This documentation covers only the streaming aspects of avserver / -avconv. All questions about parameters for avconv, codec questions, -etc. are not covered here. Read @file{avconv.html} for more -information. - -@section How does it work? - -avserver receives prerecorded files or FFM streams from some avconv -instance as input, then streams them over RTP/RTSP/HTTP. - -An avserver instance will listen on some port as specified in the -configuration file. You can launch one or more instances of avconv and -send one or more FFM streams to the port where avserver is expecting -to receive them. Alternately, you can make avserver launch such avconv -instances at startup. - -Input streams are called feeds, and each one is specified by a <Feed> -section in the configuration file. - -For each feed you can have different output streams in various -formats, each one specified by a <Stream> section in the configuration -file. - -@section Status stream - -avserver 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 -<Stream status.html> -Format status - -# Only allow local people to get the status -ACL allow localhost -ACL allow 192.168.0.0 192.168.255.255 -</Stream> -@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 What do I need? - -I use Linux on a 900 MHz Duron with a cheapo Bt848 based TV capture card. I'm -using stock Linux 2.4.17 with the stock drivers. [Actually that isn't true, -I needed some special drivers for my motherboard-based sound card.] - -I understand that FreeBSD systems work just fine as well. - -@section How do I make it work? - -First, build the kit. It *really* helps to have installed LAME first. Then when -you run the avserver ./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 avconv: - -@example -./avserver -f doc/avserver.conf & -./avconv -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://<linuxbox>: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 avserver.conf file to suit your needs (in terms of -frame rates etc). Then install avserver and avconv, 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 avconv 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 avconv. - -@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 -avserver parameters must match the original parameters used to record the -file. If they do not, then avserver 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 -avserver.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, avserver (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 avserver.conf that will -add the 15 second prebuffering on all requests that do not otherwise -specify a time. In addition, avserver 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 avserver.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 avserver, 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 - -@chapter Options -@c man begin OPTIONS - -@include avtools-common-opts.texi - -@section Main options - -@table @option -@item -f @var{configfile} -Use @file{configfile} instead of @file{/etc/avserver.conf}. -@item -n -Enable no-launch mode. This option disables all the Launch directives -within the various <Stream> sections. Since avserver will not launch -any avconv 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 -@c man end - -@ignore - -@setfilename avserver -@settitle avserver video server - -@c man begin SEEALSO - -avconv(1), avplay(1), avprobe(1), the @file{avserver.conf} -example and the Libav HTML documentation -@c man end - -@c man begin AUTHORS -The Libav developers -@c man end - -@end ignore - -@bye |
