glasscoder

Name

glasscoder — Minimalist audio encoder for live streaming

Synopsis

glasscoder [OPTIONS]

Description

glasscoder(1) is an audio encoder that is capable of generating live streams using a variety of formats and sending them to an Icecast or Shoutcast audio streaming server or posting them as HTTP Live Streams [HLS]. It is also capable of acting as an Icecast-compatible server in its own right, serving streams directly to client players and thus eliminating the need for an intervening Icecast server instance.

glasscoder(1) has no GUI or configuration file components at all; its sole 'user interface' being its command-line invocation. As such, it is particularly well suited for being driven by an external process or controller such as glassgui(1) or glasscommander(1).

Options

--audio-atomic-frames

Emit a stream consisting of self-contained frames --e.g. by disabling the MPEG-1 bit reservoir. Useful mostly for debugging.

--audio-bitrate=kbps

The constant stream data rate in kilobits per second. Default value is 128. Use of this option is mutually exclusive with that of the --audio-quality option (see below).

--audio-channels=chans

The number of audio channels to use. Valid values are 1 or 2. Default value is 2.

--audio-device=type

The type of audio device to use. The default value is JACK. See the DEVICE OPTIONS section (below) for the options appropriate for each audio device type. Valid values are:

ALSA
The Advanced Linux Sound Architecture.

ASIHPI
AudioScience HPI.

FILE
Stream directly from a file.

JACK
The Jack Audio Connection Kit.

--audio-format=fmt

The audio encoding format to use. The default value is VORBIS. Valid fmt values are:

AAC
MPEG-2 Advanced Audio Coding (Main Profile)

AACP
MPEG-4 Advanced Audio Coding (High Efficiency Profile)

MP2
MPEG-1/1.5 Layer 2

MP3
MPEG-1/1.5 Layer 3

PCM16
PCM16 Uncompressed

VORBIS
Ogg Vorbis

--audio-quality=qual

Use variable bitrate streaming at the given audio quality. qual can be in the range 0.0 (lowest quality) to 1.0 (highest). Use of this option is mutually exclusive with that of the --audio-bitrate option (see above).

--audio-samplerate=rate

The audio sample rate to use for streaming. If the underlying audio layer is operating at a different sample rate, the input will be automatically resampled to this rate. Default value is 44100.

--errors-string=string

Prepend string to messages sent to the syslog service (see the --errors-to option, below). Useful for disambiguating messages from multiple glasscoder(1) instances.

--errors-to=dest

Send error messages to dest (default standard error). Valid destinations are:

STDERR
Standard error.

SYSLOG
The system syslog service.

STDOUT
Standard output,in machine readable format (useful for communication with another 'controller' program). See also the --meter-data option below.

--help

Print a short usage message and exit.

--list-codecs

Print a list of available codecs and then exit.

--list-devices

Print a list of available source devices and then exit.

--metadata-port=port

Accept metadata updates via HTTP at port port. Default value is 0, which disables metadata updates. Both IceCast and ShoutCast style metadata updates are supported (but see the NOTES section below).

--meter-data

Output meter level updates on standard output. Useful for driving an external metering display.

--server-auth=[username][:password]

The authentication parameters to use. This parameter has no default.

--server-exit-on-last

Exit the program upon closure of the last player connection. This setting is used only by the IceStreamer server.

--server-max-connections=conns

Allow a maximum of conns simultaneous player connections. Players beyond this maximum attempting to connect will receive an immediate TCP disconnect before the HTTP handshake. This setting is used only by the IceStreamer server.

--server-pipe=pathname

Location to create a UNIX socket for piping connection socket descriptors. Useful for implementing proxy connectors for the IceStreamer server. For further details about this feature, see the Proxy Connections section of the glasscoder-ipc(7) man page. The default is to create no UNIX socket. This setting is used only by the IceStreamer server.

--server-script-down=cmd

Run the command cmd when the connection enters the disconnected state.

--server-script-up=cmd

Run the command cmd when the connection enters the connected state.

--server-start-connections=conns

Do not start the audio transport until at least conns connections have been established. Used only by the IceStreamer server in conjunction with the FILE audio device. Default value is 0 --i.e. start the transport immediately.

--server-type=type

The type of streaming server to use (default is Icecast2). Valid values for type are:

FILE
Local file
FILEARCHIVE
Local file archive. Stream to a set of files on the local system, starting a new file at the beginning of each hour.
HLS
HLS/HTTP Live Streaming
IceCast2
IceCast v2
IceOut
Output an Icecast-compatible stream on standard output.
IceStreamer
Stream directly to players using the internal Icecast-compatible server.
Shout1
Shoutcast v1
Shout2
Shoutcast v2

--server-url=url

The URL describing the server resource to stream to. When used with a --server-type of IceStreamer, the host part of the URL is used to specify the address of the network interface to use for streaming (use 0.0.0.0 to indicate ALL interfaces). This parameter has no default.

--stream-aim=aim

The AOL Instant Messenger ID to associate with the stream. There is no default value. This setting is used only by Shoutcast servers.

--stream-description=string

The string to show as the stream description. There is no default value. This setting is used only by Icecast servers.

--stream-genre=string

The string to show as the stream genre. There is no default value. This setting is used only by Icecast and Shoutcast servers.

--stream-icq=icq

The ICQ ID to associate with the stream. There is no default value. This setting is used only by Shoutcast servers.

--stream-irc=irc

The Internet Relay Chat ID to associate with the stream. There is no default value. This setting is used only by Shoutcast servers.

--stream-name=string

The string to show as the stream name. There is no default value. This setting is used only by Icecast and Shoutcast servers.

--stream-timestamp-offset=offset

The offset to add to the value of stream timestamps, in seconds. Default value is 0. This setting is used only for HLS streams.

--stream-url=url

The URL to show for a page giving more information about the stream. There is no default value. This setting is used only by Icecast and Shoutcast servers, but is ignored by Shoutcast v2 servers.

--verbose

Increase verbosity level of information printed to standard error. WARNING: this may cause cleartext passwords to printed!

--version

Output version information and exit.

Device Options

Advanced Linux Sound Architecture (--audio-device=ALSA)

--alsa-device=dev: The name of the ALSA device to use. If no --audio-device option is given, then the hw:0 device will be used.

AudioScience HPI (--audio-device==ASIHPI)

--asihpi-adapter-index=index

The index number of the audio adapter to use.

--asihpi-input-index=index

The number of the input audio stream to use on the specified adapter.

--asihpi-input-gain=gain

The gain to apply to the input audio on the specified adapter in dB. Valid values are -100 to +20 inclusive. Default value is 0.

--asihpi-channel_mode=mode

The channel mode for the input audio on the specified adapter. The default value is NORMAL. Valid values are:

NORMAL
Left signal goes to left channel, right signal goes to right channel.
SWAP
Left signal goes to right channel, right signal goes to left channel.
LEFT
Left signal goes to both left and right channels.
RIGHT
Right signal goes to both left and right channels.

--asihpi-input-source=src-node

The input source to use on the specified adapter. See the HPI Source Nodes section below for the list of valid src-node values. The default value is LINEIN.

--asihpi-input-type=src-node

The input type to use on the specified adapter. See the HPI Source Nodes section below for the list of valid src-node values. The default value is LINEIN.

HPI Source Nodes

The following values can used for the --asihpi-input-source and --asihpi-input-type options above:

NONE , OSTREAM: Internal output stream
LINEIN: Generic input signal
AESEBU: AES3 digital input
TUNER: Tuner
RF: RF input
CLOCK: Clock source
BITSTREAM: Raw bitstream
MIC: Microphone
COBRANET: CobraNet
ANALOG: Analog input
ADAPTER: Adapter
RTP , INTERNAL: Device internal
AVB: AVB input

Direct File Streaming (--audio-device=FILE)

--file-name=name: The name of the file to stream. If no --file-name option is given, then the name of the file will be read from standard input.

The Jack Audio Connection Kit (--audio-device=JACK)

--jack-server-name=name: The name of the JACK server instance to use.
--jack-client-name=name: The name of the JACK client to use. Default is glasscoder.

Notes

HTTP Live Streams [HLS] require support for the HTTP PUT and DELETE methods on the publishing web server. See the GlassCoder documentation directory for a sample configuration for the Apache Web Server.

Not all server backends support all types of metadata. glasscoder(1) supports both IceCast- and ShoutCast-style metadata updates and will attempt to impedance-match updates to the server type as best as possible.

Author

Fred Gleason <fredg@paravelsystems.com>