'\" t
.\"		Title: glasscoder
.\"    Author: Fred Gleason <fredg@paravelsystems.com>
.\" Generator: DocBook XSL Stylesheets v1.79.1 <http://docbook.sf.net/>
.\"		 Date: 01/27/2020
.\"    Manual: Linux Audio Manual
.\"    Source: October 2019
.\"  Language: English
.\"
.TH "GLASSCODER" "1" "01/27/2020" "October 2019" "Linux Audio Manual"
.\" -----------------------------------------------------------------
.\" * Define some portability stuff
.\" -----------------------------------------------------------------
.\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
.\" http://bugs.debian.org/507673
.\" http://lists.gnu.org/archive/html/groff/2009-02/msg00013.html
.\" ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
.ie \n(.g .ds Aq \(aq
.el		  .ds Aq '
.\" -----------------------------------------------------------------
.\" * set default formatting
.\" -----------------------------------------------------------------
.\" disable hyphenation
.nh
.\" disable justification (adjust text to left margin only)
.ad l
.\" -----------------------------------------------------------------
.\" * MAIN CONTENT STARTS HERE *
.\" -----------------------------------------------------------------

.SH "NAME"
glasscoder \- Minimalist audio encoder for live streaming

.SH "SYNOPSIS"

.HP \w'\fBglasscoder\fR\ 'u
\fBglasscoder\fR [\fIOPTIONS\fR]
.br

.SH "DESCRIPTION"

.PP
\fBglasscoder\fR(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\&.

.PP
\fBglasscoder\fR(1)
has no GUI or configuration file components at all; its sole \*(Aquser interface\*(Aq being its command\-line invocation\&. As such, it is particularly well suited for being driven by an external process or controller such as
\fBglassgui\fR(1)
or
\fBglasscommander\fR(1)\&.

.SH "OPTIONS"

.PP
\fB\-\-audio\-atomic\-frames\fR
.RS 4
Emit a stream consisting of self\-contained frames \-\-e\&.g\&. by disabling the MPEG\-1 bit reservoir\&. Useful mostly for debugging\&.
.RE

.PP
\fB\-\-audio\-bitrate=\fR\fIkbps\fR
.RS 4
The constant stream data rate in kilobits per second\&. Default value is
\fB128\fR\&. Use of this option is mutually exclusive with that of the
\fB\-\-audio\-quality\fR
option (see below)\&.
.RE

.PP
\fB\-\-audio\-channels=\fR\fIchans\fR
.RS 4
The number of audio channels to use\&. Valid values are
\fB1\fR
or
\fB2\fR\&. Default value is
\fB2\fR\&.
.RE

.PP
\fB\-\-audio\-device=\fR\fItype\fR
.RS 4
The type of audio device to use\&. The default value is
\fBJACK\fR\&. See the
\fBDEVICE OPTIONS\fR
section (below) for the options appropriate for each audio device type\&. Valid values are:

.PP
\fBALSA\fR
.RS 4
The Advanced Linux Sound Architecture\&.
.RE
.sp

.PP
\fBFILE\fR
.RS 4
Stream directly from a file\&.
.RE
.sp

.PP
\fBJACK\fR
.RS 4
The Jack Audio Connection Kit\&.
.RE
.sp

.RE

.PP
\fB\-\-audio\-format=\fR\fIfmt\fR
.RS 4
The audio encoding format to use\&. The default value is
\fBVORBIS\fR\&. Valid
\fIfmt\fR
values are:
.PP
\fBMP3\fR
.RS 4
MPEG\-1/1\&.5 Layer 3
.RE
.sp

.PP
\fBOPUS\fR
.RS 4
Ogg Opus (RFC\-6716)
.RE
.sp

.PP
\fBPCM16\fR
.RS 4
PCM16 Uncompressed
.RE
.sp

.PP
\fBVORBIS\fR
.RS 4
Ogg Vorbis
.RE
.sp
.RE

.PP
\fB\-\-audio\-quality=\fR\fIqual\fR
.RS 4
Use variable bitrate streaming at the given audio quality\&.
\fIqual\fR
can be in the range
\fB0\&.0\fR
(lowest quality) to
\fB1\&.0\fR
(highest)\&. Use of this option is mutually exclusive with that of the
\fB\-\-audio\-bitrate\fR
option (see above)\&.
.RE

.PP
\fB\-\-audio\-samplerate=\fR\fIrate\fR
.RS 4
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
\fB44100\fR\&.
.RE

.PP
\fB\-\-errors\-string=\fR\fIstring\fR
.RS 4
Prepend
\fIstring\fR
to messages sent to the
\fBsyslog\fR
service (see the
\fB\-\-errors\-to\fR
option, below)\&. Useful for disambiguating messages from multiple
\fBglasscoder\fR(1)
instances\&.
.RE

.PP
\fB\-\-errors\-to=\fR\fIdest\fR
.RS 4
Send error messages to
\fIdest\fR
(default standard error)\&. Valid destinations are:

.PP
\fBSTDERR\fR
.RS 4
Standard error\&.
.RE
.sp

.PP
\fBSYSLOG\fR
.RS 4
The system syslog service\&.
.RE
.sp

.PP
\fBSTDOUT\fR
.RS 4
Standard output,in machine readable format (useful for communication with another \*(Aqcontroller\*(Aq program)\&. See also the
\fB\-\-meter\-data\fR
option below\&.
.RE
.sp

.RE

.PP
\fB\-\-help\fR
.RS 4
Print a short usage message and exit\&.
.RE

.PP
\fB\-\-list\-codecs\fR
.RS 4
Print a list of available codecs and then exit\&.
.RE

.PP
\fB\-\-list\-devices\fR
.RS 4
Print a list of available source devices and then exit\&.
.RE

.PP
\fB\-\-metadata\-port=\fR\fIport\fR
.RS 4
Accept metadata updates via HTTP at port
\fIport\fR\&. Default value is
\fB0\fR, which disables metadata updates\&. See the METADATA section (below) for information regarding the supported update formats\&.
.RE

.PP
\fB\-\-meter\-data\fR
.RS 4
Output meter level updates on standard output\&. Useful for driving an external metering display\&.
.RE

.PP
\fB\-\-server\-auth=\fR[\fIusername\fR][\fB:\fR\fIpassword\fR]
.RS 4
The authentication parameters to use\&. This parameter has no default\&.
.RE

.PP
\fB\-\-server\-exit\-on\-last\fR
.RS 4
Exit the program upon closure of the last player connection\&. This setting is used only by the IceStreamer server\&.
.RE

.PP
\fB\-\-server\-max\-connections=\fR\fIconns\fR
.RS 4
Allow a maximum of
\fIconns\fR
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\&.
.RE

.PP
\fB\-\-server\-pipe=\fR\fIpathname\fR
.RS 4
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
\fBglasscoder\-ipc\fR(7)
man page\&. The default is to create no UNIX socket\&. This setting is used only by the IceStreamer server\&.
.RE

.PP
\fB\-\-server\-script\-down=\fR\fIcmd\fR
.RS 4
Run the command
\fIcmd\fR
when the connection enters the
disconnected
state\&.
.RE

.PP
\fB\-\-server\-script\-up=\fR\fIcmd\fR
.RS 4
Run the command
\fIcmd\fR
when the connection enters the
connected
state\&.
.RE

.PP
\fB\-\-server\-start\-connections=\fR\fIconns\fR
.RS 4
Do not start the audio transport until at least
\fIconns\fR
connections have been established\&. Used only by the IceStreamer server in conjunction with the
\fBFILE\fR
audio device\&. Default value is
\fB0\fR
\-\-i\&.e\&. start the transport immediately\&.
.RE

.PP
\fB\-\-server\-type=\fR\fItype\fR
.RS 4
The type of streaming server to use (default is
\fBIcecast2\fR)\&. Valid values for
\fItype\fR
are:

.PP
\fBFILE\fR
.RS 4
Local file
.RE

.PP
\fBFILEARCHIVE\fR
.RS 4
Local file archive\&. Stream to a set of files on the local system, starting a new file at the beginning of each hour\&.
.RE

.PP
\fBHLS\fR
.RS 4
HLS/HTTP Live Streaming
.RE

.PP
\fBIceCast2\fR
.RS 4
IceCast v2
.RE

.PP
\fBIceOut\fR
.RS 4
Output an Icecast\-compatible stream on standard output\&.
.RE

.PP
\fBIceStreamer\fR
.RS 4
Stream directly to players using the internal Icecast\-compatible server\&.
.RE

.PP
\fBShout1\fR
.RS 4
Shoutcast v1
.RE

.PP
\fBShout2\fR
.RS 4
Shoutcast v2
.RE
.sp

.RE

.PP
\fB\-\-server\-url=\fR\fIurl\fR
.RS 4
The URL describing the server resource to stream to\&. See the SUPPORTED URL SCHEMES section (below) for a list of what URL schemes are appropriate for which server types\&.
.sp

When used with a
\fB\-\-server\-type\fR
of
\fBIceStreamer\fR, the host part of the URL is used to specify the address of the network interface to use for streaming (use
\fB0\&.0\&.0\&.0\fR
to indicate ALL interfaces)\&. This parameter has no default\&.
.RE

.PP
\fB\-\-server\-user\-agent=\fR\fIagent\-string\fR
.RS 4
The
User\-Agent
header value to use when connecting to external servers\&. Default value is
\fBGlassCoder/1\&.0\&.0\fR\&. This setting is used only by
\fBIceCast2\fR
and
\fBHLS\fR
servers\&.
.RE

.PP
\fB\-\-stream\-aim=\fR\fIaim\fR
.RS 4
The AOL Instant Messenger ID to associate with the stream\&. There is no default value\&. This setting is used only by Shoutcast servers\&.
.RE

.PP
\fB\-\-stream\-description=\fR\fIstring\fR
.RS 4
The string to show as the stream description\&. There is no default value\&. This setting is used only by Icecast servers\&.
.RE

.PP
\fB\-\-stream\-genre=\fR\fIstring\fR
.RS 4
The string to show as the stream genre\&. There is no default value\&. This setting is used only by Icecast and Shoutcast servers\&.
.RE

.PP
\fB\-\-stream\-icq=\fR\fIicq\fR
.RS 4
The ICQ ID to associate with the stream\&. There is no default value\&. This setting is used only by Shoutcast servers\&.
.RE

.PP
\fB\-\-stream\-irc=\fR\fIirc\fR
.RS 4
The Internet Relay Chat ID to associate with the stream\&. There is no default value\&. This setting is used only by Shoutcast servers\&.
.RE

.PP
\fB\-\-stream\-name=\fR\fIstring\fR
.RS 4
The string to show as the stream name\&. There is no default value\&. This setting is used only by Icecast and Shoutcast servers\&.
.RE

.PP
\fB\-\-stream\-timestamp\-offset=\fR\fIoffset\fR
.RS 4
The offset to add to the value of stream timestamps, in seconds\&. Default value is
\fB0\fR\&. This setting is used only for HLS streams\&.
.RE

.PP
\fB\-\-stream\-url=\fR\fIurl\fR
.RS 4
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\&.
.RE

.PP
\fB\-\-verbose\fR
.RS 4
Increase verbosity level of information printed to standard error\&. WARNING: this may cause cleartext passwords to printed!
.RE

.PP
\fB\-\-version\fR
.RS 4
Output version information and exit\&.
.RE
.SH "DEVICE OPTIONS"

.PP
\fBAdvanced Linux Sound Architecture\fR (\fB\-\-audio\-device=\fR\fBALSA\fR)
.RS 4
.PP
\fB\-\-alsa\-device=\fR\fIdev\fR
.RS 4
The name of the ALSA device to use\&. If no
\fB\-\-audio\-device\fR
option is given, then the
\fBhw:0\fR
device will be used\&.
.RE
.sp
.RE

.PP
\fBDirect File Streaming\fR (\fB\-\-audio\-device=\fR\fBFILE\fR)
.RS 4
.PP
\fB\-\-file\-name=\fR\fIname\fR
.RS 4
The name of the file to stream\&. If no
\fB\-\-file\-name\fR
option is given, then the name of the file will be read from standard input\&.
.RE
.sp
.RE

.PP
\fBThe Jack Audio Connection Kit\fR (\fB\-\-audio\-device=\fR\fBJACK\fR)
.RS 4
.PP
\fB\-\-jack\-client\-name=\fR\fIname\fR
.RS 4
The name of the JACK client to use\&. Default is
\fBglasscoder\fR\&.
.RE
.PP
\fB\-\-jack\-gain=\fR\fIgain\fR
.RS 4
Apply a fixed gain of
\fIgain\fR
dB before encoding\&. Default is
\fB0\fR
dB\&.
.RE
.PP
\fB\-\-jack\-server\-name=\fR\fIname\fR
.RS 4
The name of the JACK server instance to use\&.
.RE
.sp
.RE

.SH "SUPPORTED URL SCHEMES"
.PP
Not all URL schemes are supported by all server types\&. The following chart breaks down the options\&.
.sp
.it 1 an-trap
.nr an-no-space-flag 1
.nr an-break-flag 1
.br
.B Table\ \&1.\ \&Supported URL Schemes by Server Type
.TS
allbox tab(:);
cB cB cB cB.
T{
Server Type
T}:T{
FILE://
T}:T{
HTTP://
T}:T{
SFTP://
T}
.T&
l c c c
l c c c
l c c c
l c c c
l c c c
l c c c
l c c c
l c c c
l s s s
l s s s
l s s s.
T{
FILE
T}:T{
Yes
T}:T{
No
T}:T{
No
T}
T{
FILEARCHIVE
T}:T{
Yes
T}:T{
No
T}:T{
No
T}
T{
HLS
T}:T{
Yes
T}:T{
Yes [1]
T}:T{
Yes [3]
T}
T{
IceCast2
T}:T{
No
T}:T{
Yes [2]
T}:T{
No
T}
T{
IceOut
T}:T{
No
T}:T{
Yes
T}:T{
No
T}
T{
IceStreamer
T}:T{
No
T}:T{
Yes
T}:T{
No
T}
T{
Shout1
T}:T{
No
T}:T{
Yes [2]
T}:T{
No
T}
T{
Shout2
T}:T{
No
T}:T{
Yes [2]
T}:T{
No
T}
T{
[1] Utilizes the HTTP \fIPUT\fR and \fIDELETE\fR methods
T}
T{
[2] Utilizes the HTTP \fIGET\fR method
T}
T{
[3] Supports \fBssh\fR(1) password authentication only
T}
.TE
.sp 1
.SH "METADATA"
.PP
GlassCoder supports the notion of two types of metadata: "channel\-based" metadata, which applies to the stream as a whole and does not change for the duration of an encoding session; and "timed" metadata, which can be changed in synchronization with the content of the audio stream\&. Channel\-based metadata can be specified by means of options given to
\fBglasscoder\fR(1)
and will be covered in detail in the sections devoted to specific server types (below)\&.
.PP
The primary mechanism for supplying timed metadata in GlassCoder is by means of a JSON document containing the desired metadata, sent to the target
\fBglasscoder\fR(1)
instance at the port specified by the
\fB\-\-metadata\-port\fR
option by means of an HTTP
\fIPOST\fR
operation\&. The basic format of the JSON document is as follows:

.sp
.if n \{\
.RS 4
.\}
.nf
{
	"Metadata": {
		"Field1": "Some value",
		"Field2": "Some other value"
	}
}
.fi
.if n \{\
.RE
.\}
.PP
Not all server types support metadata, and those that do utilize wildly different schemas\&. Following is a breakdown of the available metadata options by server type:
.SS "IceCast2"
.sp
.it 1 an-trap
.nr an-no-space-flag 1
.nr an-break-flag 1
.br
.ps +1
\fBChannel Metadata\fR
.RS 4
.PP
IceCast2 supports the following channel metadata fields:

.PP
Name
.RS 4
Specified by the
\fB\-\-stream\-name\fR
option\&.
.RE
.PP
Description
.RS 4
Specified by the
\fB\-\-stream\-description\fR
option\&.
.RE
.PP
URL
.RS 4
Should be a link to content related to the stream\&. Specified by the
\fB\-\-stream\-url\fR
option\&.
.RE
.PP
Genre
.RS 4
Should be a single word describing the nature of the stream content\&. Specified by the
\fB\-\-stream\-genre\fR
option\&.
.RE
.RE
.sp
.it 1 an-trap
.nr an-no-space-flag 1
.nr an-break-flag 1
.br
.ps +1
\fBTimed Metadata\fR
.RS 4
.PP
IceCast2 provides one field of text, called
StreamTitle, which can be dynamically updated to reflect the content currently playing on the stream\&. By convention, this is usually formatted as \*(Aq\fBArtist\fR
\-
\fBTitle\fR\*(Aq on streams containing musical content\&.
.PP
For example, to set the
StreamTitle
field to
\fBThe Beatles \- Hey Jude\fR, the following JSON could be used:
.sp
.if n \{\
.RS 4
.\}
.nf
{
	"Metadata": {
		"StreamTitle": "The Beatles \- Hey Jude"
	}
}

.fi
.if n \{\
.RE
.\}
.sp

.RE
.sp
.it 1 an-trap
.nr an-no-space-flag 1
.nr an-break-flag 1
.br
.ps +1
\fBLegacy Interface\fR
.RS 4
.PP
In addition to the primary JSON interface, the
StreamTitle
can be set by sending an HTTP
\fIGET\fR
request to a running
\fBglasscoder\fR(1)
instance, using the TCP port specified in the
\fB\-\-metadata\-port=\fR\fIport\fR
option\&. The request must be in the following format:
.sp
.if n \{\
.RS 4
.\}
.nf
http://\fIhostname\fR:\fItcp\-port\fR/admin/metadata?mount=\fImount\-point\fR&mode=updinfo&song=\fIstring\fR

.fi
.if n \{\
.RE
.\}
.sp

.PP
Where:

.PP
\fIhostname\fR
\- The hostname or IP address of the system running
\fBglasscoder\fR(1)

.PP
\fItcp\-port\fR
\- The TCP port number specified in the
\fB\-\-metadata\-port\fR
option to
\fBglasscoder\fR(1)

.PP
\fImount\-point\fR
\- The mountpoint of the stream

.PP
\fIstring\fR
\- The string to set, encoded as specified in Section 2 of RFC3986

.PP
For example, to set a string of "The Beatles \- Hey Jude" via a
\fBglasscoder\fR(1)
instance running at
\fBencoder\&.example\&.com\fR
with a
\fB\-\-metadata\-port\fR
value of
\fB1234\fR
for a mountpoint of
\fBMyStream\fR, the URL would be:

.PP
\fB http://encoder\&.example\&.com:1234/admin/metadata?mount=MyStream&mode=updinfo&song=The%20Beatles%20\-%20Hey%20Jude \fR
.RE

.SS "ShoutCast"
.sp
.it 1 an-trap
.nr an-no-space-flag 1
.nr an-break-flag 1
.br
.ps +1
\fBChannel Metadata\fR
.RS 4
.PP
ShoutCast supports the following channel metadata fields:

.PP
Name
.RS 4
Specified by the
\fB\-\-stream\-name\fR
option\&.
.RE
.PP
URL
.RS 4
Should be a link to content related to the stream\&. Specified by the
\fB\-\-stream\-url\fR
option\&.
.RE
.PP
Genre
.RS 4
Should be a single word describing the nature of the stream content\&. Specified by the
\fB\-\-stream\-genre\fR
option\&.
.RE
.PP
ICQ ID
.RS 4
Should be User Identification Number for an ICQ user associated with the stream content\&. Specified by the
\fB\-\-stream\-icq\fR
option\&.
.RE
.PP
AOL Instant Messenger ID
.RS 4
Should be an ID for an AOL Instant Messenger user associated with the stream content\&. Specified by the
\fB\-\-stream\-aim\fR
option\&.
.RE
.PP
IRC ID
.RS 4
Should be an ID for an Internet Relay Chat channel associated with the stream content\&. Specified by the
\fB\-\-stream\-irc\fR
option\&.
.RE
.RE
.sp
.it 1 an-trap
.nr an-no-space-flag 1
.nr an-break-flag 1
.br
.ps +1
\fBTimed Metadata\fR
.RS 4
.PP
ShoutCast provides two fields of text which can be dynamically updated to reflect the content currently playing on the stream, called
StreamTitle
and
StreamUrl\&. By convention, the
StreamTitle
is usually formatted as \*(Aq\fBArtist\fR
\-
\fBTitle\fR\*(Aq on streams containing musical content, while
StreamUrl
is used to provide a URL whence stream specific content \-\-e\&.g\&. album cover art \-\- can be retrieved\&.
.PP
For example, to set the
StreamTitle
field to
\fBThe Beatles \- Hey Jude\fR
and the
StreamUrl
field to
\fBhttp://images\&.example\&.com/1234\&.png\fR, the following JSON could be used:
.sp
.if n \{\
.RS 4
.\}
.nf
{
	"Metadata": {
		"StreamTitle": "The Beatles \- Hey Jude",
		"StreamUrl": "http://images\&.example\&.com/1234\&.png"
	}
}

.fi
.if n \{\
.RE
.\}
.sp

.if n \{\
.sp
.\}
.RS 4
.it 1 an-trap
.nr an-no-space-flag 1
.nr an-break-flag 1
.br
.ps +1
\fBNote\fR
.ps -1
.br

The use of either of these fields is optional in any given metadata
update\&. If only one field is given, the other will remain unchanged\&.
.sp .5v
.RE
.RE
.sp
.it 1 an-trap
.nr an-no-space-flag 1
.nr an-break-flag 1
.br
.ps +1
\fBLegacy Interface\fR
.RS 4
.PP
In addition to the primary JSON interface, the
StreamTitle
and
StreamUrl
fields can be set by sending an HTTP
\fIGET\fR
request to a running
\fBglasscoder\fR(1)
instance, using the TCP port specified in the
\fB\-\-metadata\-port=\fR\fIport\fR
option\&. The request must be in the following format:
.sp
.if n \{\
.RS 4
.\}
.nf
http://\fIhostname\fR:\fItcp\-port\fR/admin\&.cgi?pass=\fIpassword\fR&mode=updinfo&song=\fIstream\-title\fR&url=\fIstream\-url\fR

.fi
.if n \{\
.RE
.\}
.sp

.PP
Where:

.PP
\fIhostname\fR
\- The hostname or IP address of the system running
\fBglasscoder\fR(1)

.PP
\fItcp\-port\fR
\- The TCP port number specified in the
\fB\-\-metadata\-port\fR
option to
\fBglasscoder\fR(1)

.PP
\fIpassword\fR
\- The ShoutCast password, encoded as specified in Section 2 of RFC3986

.PP
\fIstream\-title\fR
\- The string to set for
StreamTitle, encoded as specified in Section 2 of RFC3986

.PP
\fIstream\-url\fR
\- The string to set for
StreamUrl, encoded as specified in Section 2 of RFC3986

.PP
For example, to set a
StreamTitle
of "The Beatles \- Hey Jude" and a
StreamUrl
of "http://image\&.example\&.com/1234\&.png" with a password of "MyPassword" via a
\fBglasscoder\fR(1)
instance running at
\fBencoder\&.example\&.com\fR
with a
\fB\-\-metadata\-port\fR
value of
\fB1234\fR, the URL would be:

.PP
\fB http://encoder\&.example\&.com:1234/admin\&.cgi?pass=MyPassword&mode=updinfo&song=The%20Beatles%20\-%20Hey%20Jude&url=http://image\&.example\&.com/1234\&.png \fR
.RE

.SS "HTTP Live Streams (HLS)"
.sp
.it 1 an-trap
.nr an-no-space-flag 1
.nr an-break-flag 1
.br
.ps +1
\fBTimed Metadata\fR
.RS 4
.PP
HLS supports timed metadata in the form of embedded ID3v2\&.4 tags\&. Available fields thus include the entire set of text tags defined in the ID3v2\&.4 frame specification (available at http://id3\&.org/id3v2\&.4\&.0\-frames)\&.
.PP
For example, a typical metadata update could use the following JSON:
.sp
.if n \{\
.RS 4
.\}
.nf
{
	"Metadata": {
		"TIT2": "Hey Jude",
		"TPE1": "The Beatles",
		"TALB": "The White Album",
		"TRSO": "WXYZ Radio"
	}
}

.fi
.if n \{\
.RE
.\}
.sp

.PP
A user defined text information frame (\fBTXXX\fR) can be sent by using the following special notation for the field identifier:
.PP
TXXX\fIdesc\fR
.PP
Where:

.PP
\fIdesc\fR
\- The TXXX Description string (see Section 4\&.2\&.6 of the ID3v2\&.4 Frame Specification)

.PP
For example:
.sp
.if n \{\
.RS 4
.\}
.nf
{
	"Metadata": {
		"TIT2": "Hey Jude",
		"TPE1": "The Beatles",
		"TALB": "The White Album",
		"TRSO": "WXYZ Radio",
		"TXXXxyz": "TXXX frame with a description string of \e"xyz\e""
	}
}

.fi
.if n \{\
.RE
.\}
.sp
.RE
.SH "NOTES"
.PP
The Debian version of GlassCoder does not support the MPEG-4 HE-AAC+ encoding, as it is non-free. The AudioScience HPI source device is excluded for the same reason.

.SH "BUGS"
.PP
SFTP:// transfers are done in "insecure" mode (due to crippled support for
\fBssh\fR(1)
host keys in
\fBcurl\fR(1))\&.
.PP
\fBssh\fR(1)
public key authentication is unsupported (due to crippled support for ed25519 keys in
\fBcurl\fR(1))\&.
.PP
Ogg metadata support is still missing\&.
.SH "AUTHOR"
.PP
Fred Gleason <fredg@paravelsystems\&.com>
.SH "SEE ALSO"
.PP
\fBglasscoder-ipc\fR(7),
\fBglasscommander\fR(1),
\fBglassgui\fR(1),
\fBjackd\fR(1)
.PP
RFC3986 \- Uniform Resource Identifier (URI): Generic Syntax
.PP
ID3v2\&.4 Native Frame Specification (http://id3\&.org/id3v2\&.4\&.0\-frames)

.SH "AUTHOR"
.PP
\fBFred Gleason\fR <\&fredg@paravelsystems\&.com\&>
.RS 4
Application Author
.RE