Flussonic Media Server Documentation

Contents

Data Source Types

A source is from where Flussonic receives a stream of video data. A source can be an IP camera, a satellite headend, an HTTP server, and so on. To specify the source of a stream, you need to know its address and the video protocol over which Flussonic receives video data, in other words, you need to know the URL.

The url parameter in the stream settings specifies the source of a video stream. This page includes examples of URLs for various protocols and other types of sources.

What not to specify as a source via the url parameter

  • Flussonic Media Server does not support the http data source type, and specifying an URL as http://host/path will result in an error. You should use a URL that explicitly specifies a video protocol — HTTP MPEG-TS, HLS, or any other protocol supported by the system.

  • Do not specify a file on the server as a source. Broadcasting of files is configured differently from live sources. Learn more in VOD file broadcasting.

Important. To send video data between Flussonic Media Servers we recommend using Flussonic's internal protocol M4F.

On this page:

M4F

We recommend using M4F to send video between Flussonic servers. This protocol is ideal for setting up replication of a DVR archive or for re-streaming individual streams in a cluster.

  • m4f://hostname:port/stream — syntax
  • m4f://flussonic.example.com/channel_01 — example

About the M4F protocol

MPEG-TS over HTTP

  • tshttp://hostname:port/stream — syntax (ingest over HTTP)
  • tshttps://hostname:port/stream — syntax (ingest over HTTPS)
  • tshttp://192.168.100.1/worldnews.ts — example of a URL

An HTTP MPEG-TS data source is, for example, VLC.

MPEG-TS over UDP

  • udp://239.255.1.1:5500 — multicast URL
  • udp://239.255.1.1:5500/192.168.10.1 — ingest of a multicast stream through the specified interface
  • udp://192.168.0.1:12345 — unicast URL. Where 192.168.0.1 is the source IP. Flussonic is filtering input UDP unicast by specified IP.

MPEG-TS over TCP

A TCP MPEG-TS data source:

  • tstcp://192.168.0.1:54321

HLS

  • hls://HOSTNAME/PATH/TO/MANIFEST.m3u8 — syntax
  • hls://10.0.0.1/news.m3u8 — example of an HLS URL
  • hls://example.com/news/index.m3u8 — example of an HLS URL.
  • hlss://HOSTNAME/PATH/TO/MANIFEST.m3u8 — syntax of ingest over HTTPS

A generic HTTP server could serve a pre-packaged HLS manifest and chunks with video data. In the case where the manifest file is static Flussonic would not be able to ingest HLS stream. Flussonic Media Server will wait for new segments to appear until till timeout, then it will restart this source and try to fetch again the existing segments.

It is possible to validate a playlist by its modification time, but this method is not very reliable. By default, Flussonic Media Server has enabled feature called "stalled check". Here, the server downloads only the new segments after the first fetch, making sure that no segments from first fetch will be used.

Sometimes you would want to make sure that your source is not a generic HTTP server, but a streaming server that will not serve outdated segments and you want to enable HLS source in ondemand configuration.

To make sure that your streaming server would not serve outdated segments in ondemand you should use this option.

Stale protection option affects stream startup time, when this option is enabled Flussonic Media Server will wait for at least 2-3 new segments before making stream available.

You can disable stale protection with this directive: skip_stalled_check=true;

Use this feature at your own risk — with it enabled, old content might be repeated over and over.

stream origin {
  url fake://fake;
}
stream input_hls {
  url hls://localhost:80/origin/index.m3u8 skip_stalled_check=true;
}

For HLS sources you can set the user_agent option:

hls://source:80/stream/index.m3u8 user_agent="Custom Agent v1.2"

RTSP

When receiving a stream from an RTSP camera, you should include the camera's IP address and the path to its RTSP stream in the URL. The path is not always published in the camera's user manual. You might need to contact the camera's vendor or manufacturer to get this information.

  • rtsp://hostname/path — syntax
  • rtsp://user:password@ip/path — URL with authorization
  • rtsp2://hostname/path — the rtsp2 protocol instructs Flussonic to transcode the audio stream into AAC. Learn more
  • rtsp://192.168.0.100/h264 — example of an RTSP URL

You can use the tracks=1 option to receive only video track.

stream fake {
  url fake://fake;
}
stream input_rtsp {
  url rtsp://localhost/fake tracks=1;
}

RTMP

  • rtmp://hostname/application/stream
  • rtmp://10.0.0.1/live/news

stream clock {
 url fake://fake;
}
stream input_rtmp {
 url rtmp://localhost:1935/static/clock;
}

The RTMP protocol requires that an RTMP URL has at least two segments. The first segment (application) is by default used as the name of the RTMP application.

If the name of the RTMP application on the server consists of more than one segments, add two slashes to the URL in order to explicitly divide the RTMP application and stream name.

File

  • file://vod-location/file.mp4 syntax
  • file://vod/bunny.mp4 a real configuration, more details about VOD path read here

Flussonic can create a loop-stream from any .mp4 or .ts file. Specify a stream source using the file:// schema.

DVB-S cards

  • url mpts-dvb://a0 program=1234

The scheme mpts-dvb:// allows capturing video from a DVB-S card directly into Flussonic. Learn more

Timeshift

  • timeshift://STREAM/3600

The timeshift:// is a scheme that allows you to create a new stream identical to the stream but with a predefined delay. In this example the delay is 3600 seconds (one hour). It is delivered from the recorded archive.

SHOUTcast

  • shout://source:80

The shout:// scheme is used to ingest SHOUTcast and ICEcast internet radio streams.

H323

  • h323://192.168.100.150

The scheme h323:// is used to ingest video via the VoIP protocol H323. Learn more

Mixer

  • mixer://stream1,stream2

Use the scheme mixer:// to mux video from the first specified stream with audio from the second one. Learn more

Mosaic

  • mosaic://cam1,cam2,cam3,cam4?fps=20&preset=ultrafast&bitrate=1024k&size=340x240&mosaic_size=4

Use the scheme mosaic:// to create a mosaic — a combination of multiple video streams in one. Learn more

MPEG-TS options

When working with tshttp://, udp://, and tstcp:// sources, you can use MPEG2-TS specific options.

Ingesting specific MPEG-TS programs and PIDs

stream clock {
  url fake://fake;
}
stream example {
  url tshttp://localhost:80/clock/mpegts program=1 pids=211;
}

Subtitles options

You can manage DVB subtitles in an output stream with the option subtitles, which has the following values:

  • drop — an output stream will have no subtitles track. See the example in Disabling subtitles below.
  • accept — an output stream will have a subtitles track in DVB, without conversion to text.
  • ocr_replace — an output stream will have a track containing subtitles converted to a text format (WebVTT).
  • ocr_add — an output stream will have two tracks containing subtitles: the original track with subtitles in DVB and a new track with text subtitles.

Accepting subtitles

By default, Flussonic Media Server always ingests subtitles from published streams. This is true for streams with either static or dynamic names. You generally don't need to explicitly set the option subtitles=accept.

Disabling subtitles

If you do not need subtitles in a stream, set the option subtitles to drop:

stream origin {
  url file://vod/subs.ts;
}
stream example {
  url tshttp://localhost:80/origin/mpegts subtitles=drop;
}

Note. For live published streams (streams with dynamic names), subtitles are always ingested and cannot be disabled. The subtitles=drop option will not work.

The option allow_subtitles is now deprecated and supported only for backward compatibility.

Converting subtitles

Learn more about recognition and conversion of DVB subtitles in Converting DVB Subtitles to WebVTT

Editing the Language descriptor in the Program Map Table (PMT)

If an incoming MPEG-TS stream does not have the Language descriptor in audio PIDs, there might be problems playing on set-top-boxes, for example, if a certain language was set as preferred.

Flussonic 20.05 allows setting or editing the language for audio tracks in output MPEG-TS. For this the option lang in an input stream settings is used. It sets the ISO 639 language codes:

stream example {
  url file://vod/multilang2.ts lang.a1=eng lang.a2=rus lang.default=eng;
}

This coniguration adds the Language descriptors to the PMT of an output stream.

HTTP options

When connecting to a stream over HTTP, you can set the User-Agent HTTP header with the user_agent option:

stream example {
  url tshttp://source:80/stream user_agent="VLC"
}

To specify a custom HTTP header, for example 'Referer':

stream example {
  url tshttp://source:80/stream header.Referer=https://flussonic.com;
}

Passing closed captions in HLS and DASH

Flussonic allows passing CEA-608/708 closed captions from MPEG-TS:

  • in the WebVTT format — to HLS
  • in the WebVTT and TTML formats — to DASH.

After transcoding a stream that has closed captions, Flussonic keeps the closed captions in the output stream.

To use this feature, add the option closed_captions=PID to the stream's URL.

For MPEG-TS streams:

stream example_stream {
  url tshttps://HOST/STREAM/mpegts closed_captions=211;
}

For HLS streams:

stream example_stream {
  url hlss://HOST/STREAM/index.m3u8 closed_captions=211;
}

To position subtitles on the video, use the option substyle valign=top|middle|bottom align=left|center|right, for example:

stream example_stream {
  url tshttps://HOST/STREAM/mpegts closed_captions=211;
  substyle valign=top align=left;
}

After the conversion, an output stream has closed captions:

Flussonic closed captions

Choosing subtitles format for DASH playback

As two formats of subtitles are included in a DASH manifest, you can choose one of them when playing an output stream:

https://HOST/STREAM/index.mpd?text=wvtt

or

https://HOST/STREAM/index.mpd?text=ttml (TTML is the default format, though)