\input texinfo   @c -*-texinfo-*-
@c %**start of header
@setfilename emms.info
@settitle The Emms Manual 0.1.23
@c %**end of header

@c CVS info:
@c $Revision: 1.24 $

@c Maintainer comments:
@c There is always work to do in a manual.

@dircategory Emacs
@direntry
* Emms: (emms).           The Emacs Multimedia System
@end direntry

@copying
 @copyright{} (c) 2004, 2005
   Mario Domgoergen, Jorgen Schaefer, Yoni Rabkin
@quotation
Permission is granted to copy, distribute and/or modify this document
under the terms of the GNU Free Documentation License, Version 1.1 or
any later version published by the Free Software Foundation; with no
Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts.  A
copy of the license is included in the section entitled "GNU Free
Documentation License".
@end quotation
@end copying

@c For printed material
@titlepage
@title The Emms Manual

@page
@vskip 0pt plus 1filll
@insertcopying
@end titlepage

@contents
@c END For printed material

@ifnottex
@node Top, Copying, (dir), (dir)
@top Emms Manual 0.1.21

This is the Manual for the Emacs Multimedia System

@menu
* Copying::             The GNU General Public License gives you permission to
                            redistribute Emms on certain terms; it also explains
                            that there is no warranty.
* The GNU FDL::         The license for this documentation.

Starting out
* Introduction::        Introduction to Emms
* Installation::        How to install Emms on your System
* Quick Setup::         Quick start in Emms
* Configuration Example::     Bare bones configuration

Emms basics
* Basic Commands::      How to control Emms with ease
* The Core File::       The inner core of Emms
* Sources::             Sources for playlists-creation
* Simple Players::      Some simple players

Advanced Features
* Info Tags::           More narrative track descriptions
* The Playlist Buffer:: Interactive Playlist
* Scoring::             Playing files based on their rating
* Extending Emms::           How to define new players and modules
* Streaming Audio::          Interface to streaming audio

Indices
* Concept Index::
* Function Index::
* Variable Index::
* Keybinding Index::

@detailmenu
--- The Detailed Node Listing ---

Here are some other nodes which are really inferiors of the ones
already listed, mentioned here so you can get to them in one step:

Installation
* Compiling Emms::      Compiling Emms into Byte-Code

Info Tags
* Ogg Info::    Reading ogg info tags
* MP3 Info::    Reading mp3 info tags
@end detailmenu

The Playlist Buffer
* Playlist Buffer::     Browsing buffer known by other players
* Playlist Popup::      Poping-up the playlist buffer
* Playlist Manipulation::         Some playlist manipulation functions

Extending Emms
* New Player::  How to define a new player

New Player
* Simple Player for @command{play}:: Example player using @command{play}
* More Complex Player:: Example of a complex player using @command{mpg321}
@end menu

@end ifnottex

@c including the relevant licenses
@include gpl.texi
@include fdl.texi

@node Introduction
@chapter Introduction

@cindex introduction

Emms is the Emacs Multi-Media System. It tries to be a clean and small
application to play multimedia files from Emacs using external
players. Many of its ideas are derived from MpthreePlayer
(http://www.nongnu.org/mp3player), but it tries to be more general and
more clean.

The basic functionality of Emms consists of three parts: The core, the
sources, and the players.

The core resides in emms.el, and provides a simple playlist and the
basic functionality to use all the other features of Emms. It provides
the common user commands and interfaces for other parts. It thinks in
tracks, where a track is the combination of a type and a name - e.g.
the track type 'file has a name that is the file name. Other track
types are possible.

To get to tracks, the core needs sources. The file emms-source-file.el
provides simple sources to interact with the file system.

When Emms finally has the sources in the playlist, it needs a player
to play them. emms-player-simple.el defines a few useful players, and
allows you to define your own in a very simple way.

Emms is easy to customise by using the modules shipped with
emms. @xref{Extending Emms}.

Emms can also be customised by using `M-x customize'.

@node Installation
@chapter Installation

@cindex installation

You need to put all the .el files of emms in a directory in your
load-path. For example, if you put all those files into ~/elisp/emms/,
then in your ~/.emacs, you should do:

@lisp
(add-to-list 'load-path "~/elisp/emms/")
@end lisp
@noindent

@menu
* Compiling Emms::      Compiling Emms into Byte-Code
@end menu

@node Compiling Emms
@section Compiling Emms

@cindex compiling

You can byte-compile Emms by first entering the directory containing the
Emms source code, followed by invoking:

@command{make}

Which will byte compile Emms. You can then invoke:

@command{make install}

Which will install Emms into your Emacs directories (provided you have
the appropriate permissions to do so on your system).

Note that Emms is a light-weight and agile program, you can therefore
run Emms just fine without byte compiling it.

@node Quick Setup
@chapter Quick setup

Emms is quite simple to set up. For the most basic needs, you will
just need the following line,

@lisp
(require 'emms)
@end lisp
@noindent

which installs the core of Emms.

Now we need to do some configuration.

The Emms module `emms-default' provides the function `emms-setup',
which is a way to quickly configure your Emms. You can add any number
of directories which contain media. The first argument is the
complexity level of the user interface. Here's an example:

@lisp
(require 'emms-default)
(emms-setup 'tiny "directory")
@end lisp

Here is a list of the interface complexity options:

@table @samp
@item minimalistic
Define the players and play directory but nothing more.
@item tiny
Features the pbi (playlist buffer interface).
@item default
Features info reading for MP3 and OGG files.
@item advanced
Features the tageditor and playlist manipulation.
@item cvs
Features playlist pop-up, pbi marking, mode-line, asynchronous loading
of tags and (of course) the kitchen sink.
@end table

Now your configuration is done.

The (optional) directory is used for
`emms-source-file-default-directory', in case you were wondering.

@node Configuration Example
@chapter Configuration Example

@cindex Configuration Example

The following code fragment provides a minimal EMMS setup without
using the layer of `emms-default'. It can maybe be used to better
understand the internals of EMMS. You can see how EMMS needs to know
about players (these are defined in `emms-player-simple') and about
sources for tracks (trivial file system based sources, such as this
`emms-directory-tree', are defined in `emms-source-file').

@lisp
(require 'emms-player-simple)
(require 'emms-source-file)
(setq emms-player-list '(emms-player-mpg321
                         emms-player-ogg123
                         emms-player-mplayer))
@end lisp
@noindent

@node Basic Commands
@chapter Basic Commands

@cindex basic commands
@cindex commands, basic

Before you can use the interface commands, you need a playlist to
start with. The following commands allow you to create or add to the
current playlist from different sources:

@defun emms-play-file file
Play the single file @var{file}.
@end defun
@defun emms-add-file file
Add the single file @var{file} to the playlist.
@end defun
@defun emms-play-directory dir
Play the single directory @var{dir}.
@end defun
@defun emms-add-directory dir
Add the single directory @var{dir} to the playlist.
@end defun
@defun emms-play-directory-tree dir
Play the entire directory tree of which @var{dir} is the top directory.
@end defun
@defun emms-add-directory-tree dir
Add the entire directory tree of which @var{dir} is the top directory.
@end defun
@defun emms-play-url url
Play streaming audio from @var{url}.
@end defun
@defun emms-add-url url
Add the streaming audio station at @var{url} to the playlist.
@end defun
@defun emms-play-m3u-playlist playlist
Play the M3U (XMMS) playlist from the file @var{playlist}.
@end defun
@defun emms-add-m3u-playlist playlist
Add an M3U (XMMS) playlist to Emms from the file @var{playlist}.
@end defun
@defun emms-play-find dir regexp
Search for files in @var{dir} matching @var{regexp} to play.
@end defun
@defun emms-add-find dir regexp
Search for files in @var{dir} matching @var{regexp} to add.
@end defun

The basic functionality of Emms is just to play music without being
noticed. It provides a few commands to skip the current track and
such, but other than that it doesn't show up. Emms provides the
following basic user commands (which you might want to bind to
keystrokes):

@defun emms-start
Start playing the current playlist
@end defun
@defun emms-stop
Stop playing
@end defun
@defun emms-next
Go to the next track in the playlist
@end defun
@defun emms-previous
Go to the previous track in the playlist
@end defun
@defun emms-shuffle
Shuffle the playlist
@end defun
@defun emms-show &optional insertp
Describe the current Emms track in the minibuffer. If @var{insertp} is
non-nil, insert the description into the current buffer instead.
@end defun

@node The Core File
@chapter The Core File

The file @file{emms.el} provides all basic functions for playing
music, generating a playlist and defining player.

@defopt emms-source-list
A list of sources Emms can get tracks from.
@lisp
(setq emms-source-list '((emms-source-directory-tree \"~/media\")))
@end lisp
@noindent
@end defopt
@defopt emms-player-list
A list of players Emms can use. You need to set this in order to play
files. Unless you use @file{emms-player-simple} you have to define a
player with @command{emms-define-player} first.
@end defopt
@defopt emms-show-format
The format to use for @command{emms-show}. The only argument %s is the
string returned by @command{emms-track-description}
@end defopt
@defopt emms-repeat-playlist
Non-nil for repeating the playlist after playing the last track.
@end defopt
@defopt emms-track-description-function
A function to be called to give a nice, user-friendly description of
the track passed to it as an argument.
@end defopt
@defopt emms-sort-lessp-function
A function that compares two tracks, and returns non-nil if the first
track should be sorted before the second (see `sort').
@end defopt
@defopt emms-playlist-changed-hook
A hook run when the playlist of Emms has changed.
@end defopt
@defopt emms-playlist-current-changed-hook
A hook run when the current track in the playlist of Emms has
changed.
@end defopt
@defopt emms-player-started-hook
A hook run when an Emms player started playing.
@end defopt
@defopt emms-player-stopped-hook
A hook run when an Emms player stopped playing.
@end defopt

@defun emms-next-noerror
Play the next track in the playlist, but don't signal an error when
we're at the end. This should be called when no player is playing.
This is a suitable function to put in @var{emms-player-stopped-hook}.
@end defun
@defun emms-sort
Sort the playlist.
@end defun
@defun emms-sort-track-name-less-p a b
Return non-nil if the track name of @var{a} is before @var{b}.
@end defun
@defun emms-track type name
Create a track with type @var{type} and name @var{name}.
@end defun
@defun emms-track-type track
Return the type of @var{track}.
@end defun
@defun emms-track-name track
Return the name of @var{track}.
@end defun
@defun emms-track-get name track &optional inexistent
Return the value of @var{name} for @var{track}. If there is no value, return
@var{inexistent} (or nil if not given).
@end defun
@defun emms-track-set track name value
Set the value of @var{name} for @var{track} to @var{value}.
@end defun
@defun emms-track-description track
A simple function to give a user-readable description of @var{track}.
If it's a file track, it's just the filename.
Else it's the type and the name with a colon in between.
@end defun
@defun emms-playlist-current
Return a description of the currently playing track.
This uses @var{emms-track-description-function}.
@end defun
@defun emms-playlist-current-track
Return the currently playing track.
@end defun
@defun emms-playlist-get n
Return a description of the @var{n}th entry of the current playlist.
This uses `emms-track-description-function'
@end defun
@defun emms-playlist-get-track n
Return the @var{n}th track of the current playlist.
@end defun
@defun emms-playlist-set-playlist new
Set the playlist to @var{new}.
This runs `emms-playlist-changed-hook'.
@end defun
@defun emms-playlist-get-playlist
Return the current playlist.
@end defun
@defun emms-playlist-set-current n
Set the current track in the playlist to @var{n} (a number).
This runs `emms-playlist-current-changed-hook'.
@end defun
@defun emms-playlist-get-current
Return the number of the current track, or nil if the playlist is
empty.
@end defun
@defun emms-playlist-next
Advance the current track to the next entry in the playlist and
return non-nil. Return nil if there is no next track.
@end defun
@defun emms-playlist-previous
Set the current track to the previous entry in the playlist and
return non-nil. Return nil if there is no previous track.
@end defun
@defun emms-playlist-add seq &optional idx
Add each track of the sequence @var{seq} to the current playlist.
Insert at @var{idx}, which defaults to the end.
@end defun
@defun emms-playlist-remove idx
Remove track at @var{idx} from playlist.
@end defun
@defun emms-playlist-shuffle
Shuffle the current playlist.
@end defun
@defun emms-playlist-sort
Sort the current playlist according to `emms-sort-lessp-function'
@end defun
@defun emms-playlist-shuffle-vector vector
Shuffle @var{vector}.
@end defun
@defun emms-playlist-sort-vector vector
Sort @var{vector} according to `emms-sort-lessp-function'.
@end defun
@defun emms-source-play lis
Play the tracks returned by @var{lis}.
@end defun
@defun emms-player-for track
Return the player which is responsible for @var{track}, or nil if
there is none.
@end defun
@defun emms-player-start track
Start playing @var{track}.
@end defun
@defun emms-player-stop
Stop the currently playing player.
@end defun
@defun emms-player-stopped
Declare that the current player has finished playing.
This should only be called by a player.
@end defun

@node Sources
@chapter Sources

@cindex sources

@defopt emms-source-file-default-directory
The default directory to look for media files.
@end defopt

@defun emms-play-find
Play all files in @var{emms-source-file-default-directory} that match
a specific regular expression.
@end defun
@defun emms-play-dired
Play marked files from the current dired buffer
@end defun
@defun emms-play-playlist
Play all files from a playlist file.
@end defun
@defun emms-source-file &optional file
An Emms source for a single file - either @var{file}, or queried from the
user.
@end defun
@defun emms-source-files files
An Emms source for a list of @var{files}.
@end defun
@defun emms-source-directory &optional dir
An Emms source for a whole directory tree - either @var{dir}, or queried
from the user
@end defun
@defun emms-source-directory-tree & optional dir
An Emms source for multiple directory trees - either @var{dir}, or the
value of @var{emms-source-file-default-directory}.
@end defun
@defun emms-source-find &optional dir regex
An Emms source that will find files in @var{dir} or
@var{emms-source-file-default-directory} that match @var{regexp}.
@end defun
@defun emms-source-file-directory-tree &optional dir
Return a list of all files under @var{dir} that match @var{regex}.
@end defun
@defun emms-source-playlist-file file
Return all files from playlist @var{file}.
@end defun
@defun emms-source-dired
Play all marked files of a dired buffer
@end defun
@defun emms-source-file-regex
Return a regexp that matches everything any player (that supports
files) can play.
@end defun
@defun emms-save-playlist filename
Export the current playlist as to @var{filename}.  See also
@command{emms-source-playlist-file}.
@end defun
@defun emms-locate
Search for REGEXP and display the results in a locate buffer
@end defun

@node Simple Players
@chapter Simple Players

@cindex players, simple

@defmac define-emms-simple-player
Returns a simple player with the use of emms-define-player.
NAME is used to construct the name of the function like
emms-player-NAME. REGEX must be a regexp that matches the
filenames the player can play. COMMAND specifies the command line
argument to call the player and ARGS are the command line
arguments.
@end defmac

@defun emms-player-simple-stop
Stop the currently playing process, if indeed there is one
@end defun
@defun emms-player-simple-start
Starts a process playing FILENAME using the specified CMDNAME with
the specified PARAMS.
@end defun
@defun emms-player-simple-sentinel
Sentinel for determining the end of process
@end defun

@node Info Tags
@chapter Info Tags

@cindex track information

The file @file{emms-info.el} provides an interface for different
methods of reading info about the files that Emms is playing, and
displaying it.

To create a method for retrieving info about a file, you create an
object like this:

@lisp
(define-emms-info-method emms-info-mp3info
  :providep 'emms-info-mp3info-providep
  :get 'emms-info-mp3info-get
  :set 'emms-info-mp3info-set)
@end lisp
@noindent

Then you register it with emms-info, by adding it to
@var{emms-info-methods-list}.

If you wish to use 'emms-info-mp3info' you will need the mp3info
program which is available at http://www.ibiblio.org/mp3info/.
Otherwise Emms will display an error when you attempt to access MP3
info.

@lisp
(add-to-list 'emms-info-methods-list 'emms-info-mp3info)
@end lisp
@noindent

There are already two predefined methods for retrieving info

@menu
* Ogg Info::    Reading ogg info tags
* MP3 Info::    Reading mp3 info tags
@end menu

@defun emms-info-get-cached track
Return cached info for the track @var{track}, nil of no cache.
@end defun
@defun emms-info-set-cached
Set cached info for @var{track} to @var{info}
@end defun
@defun emms-info-method-for track
Return an info-method suitable for @var{track}.
@end defun
@defun emms-info-get track &optional dont-use-cached
Return an emms-info structure representing the track @var{track}.
if @var{dont-USE-CACHED} is non-nil, then always read from the file.
@end defun
@defun emms-info-get-multiple callback tracks &optional dont-use-cached
Asynchronously get all info tags from the tracks in the listlaw
@var{tracks}. For each file, call @var{callback} with the track and the info
structure.
@end defun
@defun emms-info-set track info
Set the info of the file @var{track} to the emms-info structure @var{info}.
@end defun
@defun emms-info-file-info-song-artist track
Returns a description of @var{track}, build from it's comments.

If @var{emms-info-methods-list} indicates how to retrieve special info
about it, use this. Otherwise returns the name alone.
@end defun

@defopt emms-info-methods-list
List of info-methods. You need to set this!
@end defopt
@defopt emms-info-cache
Boolean value, indicating whether or not to use a cache for
info-structures.
@end defopt
@defopt emms-info-get-multiple-idletime
The number of seconds emacs should be idle to get the next info.
Increase this if emacs becomes unresponsive when building the
playlist.
@end defopt

@node Ogg Info
@section Ogg Info
The file @file{emms-info-ogg.el} provides an interface to retrieving
comments from ogg-files, using Lawrence Mitchells ogg-comment.el.

To activate, put something like this in your ~/.emacs:

@lisp
(require 'emms-info-ogg)
(add-to-list 'emms-player-alist
             '("\\.ogg$" . emms-info-ogg-comments))
@end lisp
@noindent

Of course, you'll also need a player if you want to actually play the
files.

@defun emms-info-ogg-comment-providep
Return non-nil if this info-method provides info for the track.
@end defun
@defun emms-info-ogg-get-comment
@end defun
@defun emms-info-ogg-comment-get
Retrieve an emms-info structure as an ogg-comment
@end defun

@node MP3 Info
@section MP3 Info

This code has been adapted from code found in mp3player.el, written by
Jean-Philippe Theberge @email{jphiltheberge@@videotron.ca}, Mario Domgoergen
@email{kanaldrache@@gmx.de} and Jorgen Schäfer @email{forcer@@forcix.cx}

To activate this method for getting info, use something like:

@lisp
(require 'emms-info-mp3info)
(add-to-list 'emms-info-methods-alist
             '("\\.mp3$" . emms-info-mp3info))
@end lisp
@noindent

Of course, you'll also need a player if you want to actually play the
files.

@defun emms-info-mp3info-providep
Return non-nil if this info-method provides info for the track.
@end defun
@defun emms-info-mp3info-set track info
Set the id3v1 tag of file @var{track} to id3info @var{info}, using the
@var{mp3info-program}.
@end defun
@defun emms-info-mp3info-get track
Get the id3v1 tag of file @var{track}, using the mp3info-program and
return an emms-info structure representing it.
@end defun

@defopt emms-info-mp3info-program-name
*The name/path of the mp3info-program.
@end defopt

@node The Playlist Buffer
@chapter The Playlist Buffer
@cindex playlist buffer

@menu
* Playlist Buffer::     Browsing buffer known by other players
* Playlist Popup::      Poping-up the playlist buffer
* Playlist Manipulation::         Some playlist manipulation functions
@end menu

@node Playlist Buffer
@section Playlist buffer

@table @code
@findex emms-pbi
@item emms-pbi
Switch to playlist buffer

The playlist-buffer *Playlist* will be created and put into
emms-pbi-mode, which give you some usefull keybinings
@end table

@table @kbd
@item ?
@kindex ? (Emms-pbi)
@findex describe-mode
Describe the keybindings
@item <mouse-2>
@kindex <mouse-2> (Emms-pbi)
@findex emms-pbi-play-current-line
Play the current line
@item RET
@kindex RET (Emms-pbi)
@findex emms-pbi-play-current-line
Play the current line
@item q
@kindex q
@findex bury-buffer
@item Q
@kindex Q
@findex emms-pbi-quit
Stops emms and kill the playlist buffer
@item f
@kindex f
@findex emms-pbi-show-current-line
Show the trackname on current line
@item s
@kindex s
@findex emms-stop
Stop Emms
@item C-y
@kindex C-y
@findex emms-pbi-yank
Yank a filename from @var{emms-kill-ring} into the playlist.
@item C-k
@kindex C-k
@findex emms-pbi-kill-line
Kill the current line from the playlist.

Send the filename to the @var{emms-kill-ring}. Make sure hooks that regenerate
the entire playlist aren't run.
@item c
@kindex c
@findex emms-pbi-recenter
Center on current playing track
@item p
@kindex p
@findex emms-previous
Play the previous track in the playlist.
@item n
@kindex n
@findex emms-next
Play the next track in the playlist.
This might behave funny in @var{emms-player-stopped-hook}, use
@var{emms-next-noerror} instead for that.
@item C-x C-s
@kindex C-x C-s
@findex emms-pbi-export-playlist
Export the current playlist as to FILENAME. See also:
@var{emms-pbi-import-playlist}.
@end table

Prior versions of emms-pbi had their own linenumbering functions. But
these functions were either error prone or very slow. And besides
there was already a emacs mode that does exactly the same: setnu.el So
we remove the linenumbering functions in favour of setnu. You can get
setnu from @url{http://www.wonderworks.com/download/setnu.el}. To get
line numbers just put the following code in your @file{~/.emacs} and put
setnu.el somewhere on your loadpath:

@lisp
(require 'setnu)
(add-hook 'emms-pbi-after-build-hook (lambda (setnu-mode 1)))
@end lisp

@defun emms-pbi
Turn on emms-playlist if prefix argument ARG is a positive integer,
off otherwise.
@end defun
@defun emms-pbi-shorten-entry-to-max-length
Cut off an entry-text to make sure it's no longer than
`emms-pbi-playlist-entry-max-length' characters long.
@end defun
@defun emms-pbi-entry-info-updated
Update the track-entry based on the info
@end defun
@defun emms-pbi-rebuild-playlist-buffer
This function rebuilds the playlist-buffer if necessary.
@end defun
@defun emms-pbi-build-playlist-buffer
Build a playlist-buffer based on the current playlist.
@end defun
@defun emms-pbi-insert-tag
Insert the TRACK tag at point.
The tag is automatically shortened by
@command{emms-pbi-shorten-entry-to-max-length'}.
@end defun
@defun emms-pbi-insert-entry
Insert an entry in the playlist
@end defun
@defun emms-pbi-async-alternative-text filename
Generates a single replacement-text for @var{filename}, to be
displayed in the playlist while the info is being loaded.
@end defun
@defun emms-pbi-update-current-face
Updates the file line with the current-face
@end defun
@defun emms-pbi-add-properties-current-line
Adds the correct faces and other properties to the current line
@end defun
@defun emms-pbi-play-current-line
Play the current line
@end defun
@defun emms-pbi-show-current-line
Show filename and info for track on current line.
@end defun
@defun emms-pbi-export-playlist filename
Export the current playlist as to @var{filename}.
@end defun
@defun emms-pbi-quit
Stops emms and kill the playlist buffer
@end defun
@defun emms-pbi-kill-line
Kill the current line from the playlist.

Send the filename to @var{emms-kill-ring}. Make sure hooks that
regenerate the entire playlist aren't run.
@end defun
@defun emms-pbi-yank
Yank a filename from `kill-ring' into the playlist.
@end defun
@defun emms-pbi-return-current-line-index
Return the index position in the playlist of the current line.
@end defun
@defun emms-pbi-recenter
Center on current playing track
@end defun

@defopt emms-pbi-playlist-entry-generate-function
The function to call for generating a single item of the
playlist. This will be called with a string argument FILENAME, and
should return the text to be inserted in the playlist.
@end defopt
@defopt emms-pbi-playlist-entry-max-length
The maximum length of an entry in the playlist. If this is nil, the
entire string provided by `emms-track-description-function'.  will be
used. Beware, the output of that function is cut off to fit the
max-length before running `emms-pbi-playlist-entry-generate-function'.
@end defopt
@defopt emms-pbi-async-alternative-text-function
The function to call for generating the replacement-text for a
playlist-item, while the info is lazy-loading. This will be called
with a string argument FILENAME, and should return the text to be
processed by emms-pbi-playlist-entry-generate-function.
@end defopt
@defopt emms-pbi-playlist-buffer-name
Name of the buffer to use as a playlist-buffer
@end defopt
@defopt emms-pbi-load-info-async
Whether or not to use emms-info.el's features for async loading
info. Defaults to t when emms-info is available, and nil otherwise.
@end defopt
@defopt emms-pbi-after-build-hook
Hook that is run after the playlist buffer is built.
That might be usefull to change the playlist buffer before the
buffer is set read-only.
@end defopt
@defopt emms-pbi-current-line-face-changed-hook
Hook that is called when the face of the current line changes.
@end defopt
@defopt emms-pbi-manually-change-song-hook
Hook that is called when the song is manually changed.
@end defopt

@node Playlist Popup
@section Playlist Popup

The emms-pbi-popup module makes it easy to popup the playlist buffer
and restore the old window configuration after choosing a new track.

This module defines the following functions:

@table @code
@findex emms-pbi-popup-playlist
@item emms-pbi-popup-playlist
Popup Playlist buffer

After changing manually the track with @command{emms-pbi-play-current-line} the
old window configuration is restored. It might be useful to bind that
function to a global-key in your .emacs, for example:

@lisp
(global-set-key (kbd "<f3>") 'emms-pbi-popup-playlist)
@end lisp

@end table

@node Playlist Manipulation
@section Playlist Manipulation

The file @file{emms-pl-manip} offers various advanced playlist-manipulations functions for
Emms.

Basically just load up this file, and check out some of these
functions.

@defun vector-sort vec pred &optional beg end
Sort a vector @var{vec}, using the predicate @var{pred}, and return the new
vector. If @var{beg} and @var{end} are specified, sort only this subrange.

@var{pred} is called with 2 elements and should return true, if the first is
less than the other.
@end defun
@defun emms-pl-manip-sort by pred
Sorts the Emms-playlist, by applying @var{by} as a function to each
filename in the list, and then comparing the results with @var{pred}.
@end defun
@defun emms-pl-manip-sort-by-filename

@end defun
@defun emms-pl-manip-sort-by-name

@end defun
@defun emms-pl-manip-sort-by-info-artist
Sort the playlist, using
@end defun
@defun emms-playlist-reshuffle
Reshuffle the playlist.
@end defun

@node Scoring
@chapter Scoring

Scoring allows you to assign scores to individual files and play media
according to your mood.

When you load @file{emms-score}, you are set to a default mood 'emms-default-mood'
A mood is a one word string describing how you feel (like "funny",
"tired", "aggressive"...)  Each mood have is own set of scoring rules.

You can change your mood with M-x @command{emms-score-change-mood}

Every music file start with a default score of 0 the command
emms-score-up-current and emms-score-down-current modify the score of
the file you are currently listening by 1 In addition, skipping a file
(with emms-skip) automatically score the file down.

With scoring on (this mean the variable @var{emms-use-scoring} is t), emms
will compare the score of the file with your tolerance to decide if it
is played or not.

The default tolerance level is 0 (or the variable
@var{emms-score-min-score}).  This mean files with a score of 0 or more will
be played and files with a score of -1 or less will be skipped.

You can change the tolerance (by 1) with
@command{emms-score-lower-tolerance} and @command{emms-score-be-more-tolerant}.

@table @code
@findex emms-score
@item emms-score
Activate scoring
@findex emms-score-change-mood
@item emms-score-change-mood
Change current mood
@findex emms-score-up-current
@item emms-score-up-current
Score up the current track
@findex emms-score-down-current
@item emms-score-down-current
Score down the current track
@findex emms-score-up-file-on-line
@item emms-score-up-file-on-line
Score up file on line
@findex emms-score-down-file-on-line
@item emms-score-down-file-on-line
Score down file on line
@findex emms-score-be-more-tolerant
@item emms-score-be-more-tolerant
Lower minimum score
@findex emms-score-lower-tolerance
@item emms-score-lower-tolerance
Raise minimum score
@end table

@node Extending Emms
@chapter Extending Emms

@cindex new players
@cindex defining players
@cindex new players, defining

Emms introduces a high abstraction layer for playing music so you can
customise a lot of things to morph Emms into @emph{your} media player.

@menu
* New Player::  How to define a new player
@end menu

@node New Player
@section New Player

The file @file{emms-player-simple.el} defines some easy players to
start with, but it shouldn't be hard to provide a function for your
favourite player. We will start with an easy example that shows how
we can use the @command{play} command under Unix to play our WAV files.

@menu
* Simple Player for @command{play}:: An example player using @command{play}
* More Complex Player:: Example of a complex player using @command{mpg321}
@end menu

@node Simple Player for @command{play}
@subsection Simple Player for @command{play}

Play is a very easy command line player for various format. If you
want your emms to play WAV files just put the following lines in you
@file{.emacs}:

@lisp
(require 'emms-player-simple)
(define-emms-simple-player play "\\.wav$" "play")
@end lisp
@noindent

Huh! Wasn't that easy?

The macro function @command{define-emms-simple-player} takes a minimum
of three arguments. The first argument (@emph{play} in our example)
defines the name of the player. It's used to name the player
functions. The second is a regexp, that defines which files to play
with our player. @emph{\\.wav$} matches any filename ending with a dot
and the string wav. The last argument is the actual command line
command we use to play our files. You can also add the path but we
just assume that the command is in your path. All arguments you add to
these three are optional. They define the command line arguments you
want to add to your argument. If you want to hear the wav file of
your favourite artist in the most possible volume use the following
line:

@lisp
(require 'emms-player-simple)
(define-emms-simple-player play "\\artist-*.wav$" "play" "--volume=100")
@end lisp
@noindent

Please notice that you have to add the arguments as strings!

The command line tool you use for @command{define-emms-simple-player}
has to take one song as argument and stop after playing that
particular song. For any other concept you will need to customise
emms a bit more...

@node More Complex Player
@subsection More Complex Player

The most players you use will be simple players so you don't need to
read this chapter. But if you are curious how you can use (almost) every
player in emms read further...

In this chapter we will use mpg321 to construct a player that
actually can pause a track, restart it and show rest time. We won't
implement all of that, but after that chapter you will know how to
define it.

The command @command{define-emms-simple-player} is just a abstraction
layer for @command{define-emms-player}, which is a little bit more
complicated but much more powerful!

@lisp
(define-emms-player "emms-mpg321-remote"
  :start 'emms-mpg321-remote-start
  :stop 'emms-mpg321-remote-stop
  :playablep 'emms-mpg321-remote-playable-p)
@end lisp
@noindent

So, that almost all! @command{define-emms-player} takes a minimum of
three arguments. The first is the name of the player. The rest are
methods with functions to call. Three methods are required: start,
stop and playable. Start says Emms how to start a track (sic!), stop
how to stop a player and playablep should return non-nil if the
player can play the track.

So we just need these three functions to get our mpg321-remote:

First we code the start function. We will check if there's a open
process and start one otherwise. Then we send a string to the process
with the filename and set a filter.

@lisp
(defun emms-mpg321-remote-start ()
  (unless (get-process "mpg321-remote")
    (setq emms-mpg321-remote-process
	  (start-process "mpg321-remote-process"
			 "*mpg321*" "mpg321" "-R" "abc"))
  (process-send-string "mpg321-remote-process"
		       (concat "l " (emms-track-name track)))
  (set-process-filter emms-mpg321-remote-process 'emms-mpg321-remote-filter)))
@end lisp
@noindent

We need the filter, as mpg321-remote won't quit after playing the
track as the simple player do. We wait until the process send the
output ``@@P 0'' (the signal of mpg321 that the song ended) to the
filter and call emms-mpg321-remote-stop.

@lisp
(defun emms-mpg321-remote-filter (process output)
  (when (string-match "@@P 0" output)
    (emms-mpg321-remote-stop)))
@end lisp
@noindent

@command{emms-mpg321-remote-stop} won't do anything interesting. It
just test if there are other files to play and close the process otherwise.

@lisp
(defun emms-mpg321-remote-stop ()
  (unless emms-playlist
    (process-send-string "mpg321-remote-process" "Q\n"))
@end lisp
@noindent

And to make that a playable example i also added
@command{emms-mpg321-remote-playablep}, which i just really steal
from @file{emms-player-simple.el}

@lisp
(defun emms-mpg321-remote-playablep (track)
       "Return non-nil when we can play this track."
       (and (eq 'file (emms-track-type track))
@end lisp
@noindent

Now we have a ready player and we could add commands like
@command{emms-mpg321-remote-pause} for example.

@node Streaming Audio
@chapter Streaming Audio

@cindex streaming audio
@cindex internet radio

Emms provides a friendly interface for managing and playing streaming
audio in addition to the Emms playlist interface. The interface is
defined in the @file{emms-streams.el} package and can be loaded by
invoking:

@lisp
(require 'emms-streams)
@end lisp

Enter the emms-streams interface by invoking M-x
@command{emms-streams}. The emms-streams interface comes with a
built-in, eclectic list of streaming audio channels from thoughout the
Web. Emms can of-course play other streams than the ones listed by
default, you are free to remove any or all of them and add your
own.@footnote{If you enjoy a particular streaming audio station on the
Web and think that it belongs in the default list, please send us a
link and we will gladly add it!}

The following is a list of the key-bindings for the emms-streams
interface:

@table @kbd
@item RET
@kindex RET (emms-streams)
@vindex emms-stream-default-action
Perform the default action when you press RET in the EMMS Stream
interface.  Can be either ``add'' or ``play''. The default is ``add'',
which adds the station under point to the Emms playlist. When
@var{emms-stream-default-action} is ``play'' then Emms will play the
streaming audio channel under point.
@item q
@kindex q (emms-streams)
@findex emms-stream-quit
Quit the emms-streams interface.
@item a
@kindex a (emms-streams)
@findex emms-stream-add-bookmark
Add a bookmark to a streaming audio URL to the list.
@item d
@kindex d (emms-streams)
@findex emms-stream-delete-bookmark
Remove a bookmark to a streaming audio URL from the list.
@item e
@kindex e (emms-streams)
@findex emms-stream-edit-bookmark
Edit the details of the bookmark under point.
@item h
@kindex h (emms-streams)
@findex describe-mode
Describe the emms-streams mode.
@item n
@kindex n (emms-streams)
@findex emms-stream-next-line
Move to the next line in the emms-streams buffer (same as C-n).
@item p
@kindex p (emms-streams)
@findex emms-stream-previous-line
Move to the previous line in the emms-streams buffer (same as C-p).
@item s
@kindex s (emms-streams)
@findex emms-stream-save-bookmarks-file
Save the bookmarks in the emms-streams interface to disk. The
bookmarks will be to the location designated in the variable
@var{emms-stream-bookmarks-file}.
@item i
@kindex i (emms-streams)
@findex emms-stream-info-bookmark
Return information about the streaming audio at the URL of the
bookmark under point. Note that this will only work if the
`emms-stream-info' has already been loaded.
@end table

@node Concept Index
@unnumbered Concept Index
@printindex cp

@node Function Index
@unnumbered Function Index
@printindex fn

@node Variable Index
@unnumbered Variable Index
@printindex vr

@node Keybinding Index
@unnumbered Keybinding Index
@printindex ky

@bye