plan9-gpl/sys/man/7/juke

.TH JUKE 7
.SH NAME
juke \- music jukebox
.SH SYNOPSIS
.B juke
[
.B \-t
]
[
.B \-w
]
[
.B \-h
.I srvhost
]
[
.B \-s
.I srvname
]
.ift .sp 0.5
.ifn .sp
.B games/jukebox
[
.B \-t
]
[
.B \-w
]
.ift .sp 0.5
.ifn .sp
.B games/jukefs
[
.B \-m
.I mountpoint
]
[
.B \-s
.I srvname
]
[
.I mapfile
]
.SH DESCRIPTION
.I Jukebox
controls a playlist server
(see
.IR playlistfs (7))
through a graphical user interface.  It connects to a music database server which reads a set of
.I map
files that describe recordings and their location.  Currently, there is
one set of maps, mostly for classical music, with some jazz and other stuff
thrown in.  These are served by
.BR jukefs ,
which presents a file system conventionally mounted at
.BR /mnt/juke .
The playlist, explained below, is managed by a file system implemented by
.IR playlistfs (7)
and normally mounted on
.BR /mnt .
.PP
.I Jukebox
is most easily started through the
.I juke
shell script.
.PP
.I Jukebox
has four windows, which can be selected by clicking the appropriate tab
at the top of the window.
.PP
Above the tab are nine buttons and a volume slider.  The
.ift buttons, shown below,
.ifn buttons
are named, from left to right,
.IR Exit ,
.IR Pause ,
.IR Play ,
.IR Halt ,
.IR Back ,
.IR Forward ,
.IR Root ,
.IR Delete ,
and
.IR Help .
The buttons are
.I active
when they are displayed in dark green (or red).  When they are pale blue
they are
.IR inactive .
The Exit button is always active; it exits the program (but leaves the playlist and music database
servers running).
.PP
The
.I browse
window is for browsing through the music and selecting music to play.
Browsing down in the music hierarchy is done by clicking button one on
an item.  Clicking button three goes back up.
Clicking button two recursively adds all files below the selected item to
the
.IR "play list" .
.PP
The selected music is displayed in the
.I playlist 
window.
The track currently playing is shown in the
.I playing
window.
.PP
The
.I Root
button browses back to the root.
.PP
The
.I Delete
button empties the playlist.
.PP
The
.I Help
displays a minimal on-line manual.
.PP
.I Play
starts playing at the beginning of the play list, or at the selected track in
the play list.
.PP
During play,
.IR Pause ,
.IR Stop ,
.IR Back ,
and
.I Forward
are active.
.I Back
and
.I Forward
go back or forward a track at a time.  The other buttons do the obvious thing.
.PP
The
.B \-t
flag chooses a tiny font, useful for handhelds.
.PP
The
.B \-w
flag creates the jukebox in a new window.  Normally, the jukebox takes over
the window in which it is invoked.
.PP
The
.B \-s
flag specifies the name under which the file descriptors of the playlist and databse servers are posted
in /srv.  This allows two or more play list servers to exist on one platform, e.g., when
there are several audio devices.  The default value of the flag is
.B $\f2user\fP
for a playlist server at
.B /srv/playlistfs.$\f2user\fP
and a database server at
.BR /srv/jukefs.$\f2user\fP .
.sp
.LP
.B Jukefs
reads a set of
.I maps
describing the music data, builds an in-memory database, and provides
lookup service to
.IR jukebox .
The default map is
.BR /sys/lib/music/map .
It consists of a hierarchical set of
.IR objects .
Each object has a type, a value, zero or more attribute-value
pairs and zero or more subobjects.    An object consists of the
type, followed by its contents between curly brackets.
Attribute value pairs consist
of a single line containing an attribute name, an equals sign, and
a value.
The value of an object is any text not containing curly brackets or equals
signs.  Here is an example:
.EX
.ps -2
.vs -2p
.sp
category {
	composer = mahler

	Gustav Mahler
	(1860 — 1911)

	work {
		path {classic/mahler}
		class = symphonic
		orchestra = rfo
		conductor = Waart,~Edo~de

		Symphony Nº 5 in c♯ (RFO, Vienna)
		performance{
			Radio Filharmonisch Orkest Holland
			Edo de Waart, conductor

			recorded: Musikverein, Vienna, May 6, 1996
		}
		command {number}
		track {
			Trauermarsch (In gemessenem Schritt. Streng. Wie ein Kondukt)
			time {13:55}
			file {034.pac}
		}
		track {
			Stürmisch bewegt, mit größter Vehemenz
			time {15:34}
			file {035.pac}
		}
		track {
			Scherzo (Kräftig, nicht zu schnell)
			time {18:54}
			file {036.pac}
		}
		track {
			Adagietto (Sehr Langsam)
			time {10:01}
			file {037.pac}
		}
		track {
			Rondo–Finale (Allegro)
			time {15:44}
			file {038.pac}
		}
	}
}
.EE
.LP
This example shows a
.I category
object for the composer Gustav Mahler (the value consists of the two
lines `Gustav Mahler' and `(1860 — 1911)') with one subobject, a
.I work
object whose value is `Symphony Nº 5 in c♯ (RFO, Vienna)'.  The work object
contains six subobjects: one
.I performance
object and five
.I track
objects.
.PP
.I Category
objects must contain exactly one attribute-value pair.  The attribute
names a subobject of the root under which this category object will
be placed.  Gustav Mahler, thus, will be placed in
Root→composer.
.IR Work ,
.IR Recording ,
.IR Part ,
and
.IR Track ,
objects all describe named containers for subunits.
A
.IR Lyrics ,
.IR Performance ,
or
.IR Soloists
object adds information to a
.IR Work ,
.IR Recording ,
.IR Part ,
or
.IR Track ,
object.  It should only contain text.
The same is true for a
.I Time
object; however, it should only be used adjacent to
.I File
objects and it should contain the running time of that file (this
is for future use).
.PP
A
.I File
object specifies a file to be played.  When the
.I Select
button is pressed, all file objects contained hierarchically in the
selected object are added to the playlist.
.PP
There are a number of pseudo objects:
.I Command
may contain either
.I sort
or
.IR number .
The
.I sort
command sorts the subobjects of the object it appears in by
.I key
or textual content.
The
.I number
commands prepends numbers to the texts of its subobjects
(e.g., for the parts in a symphony)
.PP
An
.I Include
object is replaced by the contents of the named file.
.PP
A
.I Key
object specifies a key for sorting subobjects.
.PP
Finally, a
.I Path
object specifies a path to be prepended to the files named in
hierarchically contained
.I File
objects.
.PP
The attribute-value value pairs arrange for entries to be made of the
current object in a
.I Category
object named by the attribute directly under the root.
.sp
.LP
The interface to the browsing database is through a file system
implemented by
.BR jukefs .
The file system synthesises a directory per object.  Each directory contains a set of files
describing the object's attributes:
.TP
.B children
contains a new-line separated list of subobject names.  For each name,
.I x
the directory
.BI /mnt/juke/ x
describes the subobject.
.TP
.B digest
contains a one-line summary of the object
.TP
.B files
is a new-line separated list of file objects contained in this object.
Each line consists of object name and file name.
.TP
.B fulltext
is the fulltextual value of the object.
.TP
.B key
contains the key by which objects are sorted
.TP
.B miniparentage
is a one-line summary of the objects and the path leading to it from the root.
This is the line displayed in the playlist and bottom browse windows of
.BR games/jukebox .
.TP
.B parent
is the object reference to the parent of this object.
.TP
.B parentage
is a full description of the path leading to this object and the object itself.
This is the string displayed in the top of the Browse and Playing windows
of
.BR games/jukebox .
.TP
.B text
is the text field of the object.
.TP
.B type
is the type of the object
.LP
.SH FILES
.BR /sys/lib/music/map :
Default map file
.BR /mnt/juke :
Default mount point for the music database.
.SH SOURCE
.B /sys/src/games/music
.SH SEE ALSO
.IR playlistfs (7),
.IR audio (7)