path: root/README

/*! \mainpage Muggle: Media Juggler for VDR

This is a plugin for the Video Disk Recorder (VDR).

Written by:                  Andi Kellner,
                             Lars von Wedel <vonwedel@web.de>,
                             Ralf Klueber <r@lf-klueber.de>, 
                             Wolfgang Rohdewald <wolfgang@rohdewald.de>

Project's homepage:          http://www.htpc-tech.de/htpc/muggle.htm

Latest version available at: http://www.htpc-tech.de/htpc/muggle-dev.htm

See the file COPYING for license information.

\section foreword PLEASE!

This is a difficult plugin. It's nice but difficult.
With difficult I mean, that due to the underlying
database, many more sources of error can occur as
opposed to other plugins.

Take some time to carefully read these instructions.
Please provide feedback to the authors whenever you
think, these instructions are not appropriate, wrong,
or useless in any other sense.

\section desc DESCRIPTION

The muggle plugin provides a database link for VDR so that selection of media becomes more flexible.
Prerequisites are describedin Section 2, Notes on Compilation are in Section 3. Before using the plugin, 
you need to import your media into the database (cf. Section 4). The configuration of VDR and startup
parameters are descibed in Section 5.

\section prereq PREREQUISITES

The plugin currently runs on versions 1.3.17- of VDR (including 1.2.6). It also compiles on 1.3.18 
but your mileage may vary. In addition, the following pieces of software are required:

 - mySQL server (tested with 4.0.18) (Debian packages mysql-server, mysql-client)
 - mySQL client libraries
   (Debian package libmysqlclient-dev or 
    http://www.mysql.org)
 - libmad (for mp3 decoding)
   (Debian package libmad0-dev or 
    http://www.underbit.com/products/mad/)
 - libtag (for ID3 tag reading/writing)
   (Debian package libtag1-dev or 
    http://developer.kde.org/~wheeler/taglib.html)
 - optionally libvorbis and libvorbisfile to replay OGG Vorbis files
   (Debian packages libvorbis-dev or
    http://www.xiph.org/ogg/vorbis/)
 - optionally libFLAC++ to replay FLAC files
   (Debian package libflac++-dev or sources from flac.sourceforge.net)
The developer versions are needed because their headers are required for compilation.
The server need not be on the same machine as the VDR. Also, music tracks can reside somewhere else,
if they are available through a remote filesystem (NFS, Samba). However, in this case you should
know what you are doing in terms of networking and security issues.

\section install INSTALLING 

Unpack the sources in PLUGINS/src below your VDR directory (i.e. where all your other plugins are.
For example (paths and version numbers may vary)

\verbatim
   cd /usr/local/src/VDR/PLUGINS/src
   tar xvjf muggle-0.1.1.tgz
\endverbatim

Establish a symlink as you would for other plugins:

\verbatim
   ln -s muggle-0.1.1 muggle
\endverbatim

Within the VDR main directory (e.g. /usr/local/src/VDR) issue

\verbatim
   make plugins
\endverbatim

This should build all relevant stuff. If you have difficulties, check that required libraries are 
in the library directories stated in the muggle Makefile.

\section import IMPORT

The import is done in two steps: First, a database is created and initialized with proper data structures (so-called schema).
Then, these data structures are filled from the ID3 tags of your music tracks.

\subsection dbsetup Setup Database

This step can be done on the database server or on some other client machine.
Within the directory scripts there are a few helpful files to support setting
up the database. Change into that directory:#

\verbatim
   cd scripts
\endverbatim

The first step is to essentially create the database:

\verbatim
   mysql -u root -p < createdb.mysql
\endverbatim

You will need to enter your root password that you choose during mySQL installation.
Next, we generate the database tables (schema):

\verbatim
   mysql -u root -p < createtables.mysql 
\endverbatim

Further, initial data about known languages, genres, sources and musictypes is fed into the database:
Execute these commands on a single line, the \ for the linebreak ist just for presentation purposes here.

\verbatim
   echo " use GiantDisc; load data local infile 'genres.txt' into table genre;" | \
      mysql -u root -p  --local-infile=1

   echo "use GiantDisc; load data local infile 'languages.txt' into table language;" | \
      mysql -u root --local-infile=1

   echo "use GiantDisc; load data local infile 'musictypes.txt' into table language;" | \
      mysql -u root --local-infile=1

   echo "use GiantDisc; load data local infile 'sources.txt' into table language;" | \
      mysql -u root --local-infile=1
\endverbatim

You can find the sequence of commands in the file scripts/make-empty-db. Use it at your own luck after making necessary modification (program paths, database names, servers, users, etc.).

Please note, that the scripts and commands above are quite basic in terms of security (e.g. no
password set for the vdr user, no proper selection of privileges). You may want to spend some
time reading the mySQL documentation in order to set up a proper configuration. Especially when
VDR and mySQL will run on different machines you'll have to invest some time into mySQL
networking and access rights.

If you want your database name to be different than 'GiantDisc' you will need to adapt the name
in the files createdb.mysql and createtables.mysql and in the commands above. Now your database
is ready for import.

\subsection importfile Import Music

The next step is to feed all music information into the database. There is a small tool called 'mugglei'
in the muggle main directory. It connects to the database, evaluates ID3 tags from a file, and writes
the tags into the database. It runs on just one file, so you need some more effort using the Unix command
'find' to take all files into consideration. 

For this step, it is helpful, that all music files are somehow gathered under a toplevel directory.
It does not matter whether there are further subdirectories which organize files into genres, artists,
album or whatever. If this is not the case, you may want to take some time to do this. Read on before
you start

You probably do not want to import all files in one go: albums on which tracks of various artists are found
(samplers) require different treatment than files of just one artist. What I did: all samplers are collected
below a special subdirectory "Assorted". Import is then run separately for those tracks. There has been discussion
about this and ideas for better solutions are welcome.

For now, let's assume your music tracks are located in /home/music and samplers are in /home/music/Assorted.

First, import the files in Assorted. This requires the flag -a to mugglei. Further flags -h, -n, -u, and -p
specify database host, name, user and password, respectively. The filename to import is given using the -f
directive. Using 'find' you can import all files for assorted albums with a command like:

\verbatim
   find Assorted -name '*' -type f -exec mugglei -a -f {} \;
\endverbatim

For reasons of simplicity, the arguments -h, -n, -u and -p are not shown. You will need them if the default
values do not apply or modify the source code accordingly (beginning of function main). Also, make sure 
that either mugglei is on your path or specify an absolute or relative path in the above command line.

For "regular" albums, the following command may be helpful:

\verbatim
   find * -path 'Assorted' -prune -o -type f -exec mugglei -f {} \;
\endverbatim

It is important that you perform all these steps from the same location so the filenames are relative to
exactly the same directory (e.g. /home/music in the example case).

Speed should not be an issue: on my machine, it takes about 10 secs to run the import of 60 assorted
albums with more than 600 tracks. Further 1200 tracks or so require 20 more secs. This depends on machine
configuration, of course.

If a track has no ID3 tags, the following defaults will be applied:

- Title: Filename will be used
- Artist: "Unknown"
- Album: "Unassigned"
- Track: 0
- Year: 0

\section config MUGGLE CONFIGURATION

Muggle uses a small set of command line parameters in order to control 
the interaction with the mySQL server. Let's look at an example:

\verbatim
  -P'muggle -h localhost -u vdr -n GiantDisc -t/home/music'
\endverbatim

The -h parameter specifies the database host, -u specifies the user,
-n is the database name. The scripts mentioned above do not make use
of passwords, but restrict database acccess on a server basis. 

The -t argument specifies the top level directory of the music files. 
On a local installation, this is the directory in which you executed the
import steps (Chapter 4.2).

\section quickuse QUICK INTRO

Quick version: select Muggle on the OSD, browse titles (using up/down and Ok),
add them using the red button. Music will start instantly while you can continue
to browse and add tracks.

During playback, Up/Down jumps forth and back in the current playlist. Yellow 
toggles play/pause mode and Ok toggles a display of the replay process. Using
Green, the display can be switched between playlist and single display mode,
Red toggles info and progress view. For VDR 1.3.6- the progress display is
"quite simple", unfortunately.

\section use DETAILED USER'S GUIDE

The core concept of the Muggle user interface is called a *selection*. That is,
as the name suggests, a selection of music tracks. Note, that a selection can be
as small as a single track (a very simple selection, indeed) or as large as the
whole music library.

Selections are used to structure all tracks (the music library) into sets (e.g. 
a selection of all tracks by an author) and subsets (e.g. the tracks of an author 
on a certain album). Such selections are built by means of keys (e.g. author 
or album) defined in the database and are displayed in the *music browser*. The
current selection in the *music browser* contains all tracks defined by the line 
the cursor is on. So if you place the cursor on the line "Pop", all tracks with
Genre Pop are selected. If you then enter Pop and go to the line "Beatles", you
narrow your selection to pop songs from the beatles.

A collection is a special selection. Collections can be defined by the user, and 
he can add or remove any selection to / from a collection. A collection has only 
one order: a number which is incremented for every added track. Otherwise, since 
a collection is also a selection, everything that is valid for selections also 
holds for collections.

Collections can be defined by the user in the sense of a playlist. This is done by
adding/removing selections to/from the *default collection*.

Changing the contents of a collection changes them directly in the data base. Saving
or loading collections is not needed.

An important term while working with Muggle is the *default collection*. This 
is a special collection which is the target of commands working on collections.
Whenever you add selections to somewhere, they will be added to the default
collection. The same happens when you remove selections.

Another important collection is the 'play' collection. This is a temporary collection.
Whatever is added to it will be played in that order. If you add something while muggle
is not playing anything, this collection will first be emptied. However 'temporary' does
not mean that its content is not saved to the data base. 

Starting from release 0.1.1 Muggle can be also used without default playlists. There are 
new menu entries "Add X to collection" and "Remove X from collection" which show a list
of all collections to choose from. The concept of a default collection still exists and
both approaches can be used in common. However, you can spceify which commands to use for
the special keys Red/Green/Blueas you like.

\subsection general General remarks

There are two main views in Muggle, the *Music browser* view and the *Collection browser*
view. You can toggle between them using the Yellow key by default, however the key binding
can be changed.

Each of the two views has associated commands. To show a summary of the commands available
for the current view press the blue key. Note, that the red, green and yellow keys do not
have a fixed meaning. Rather, while the commands for a certain view are displayed, you can
press red/green/yellow to make the respective key execute the command currently selected
(highlighted) by the cursor. The commands you choose for red/green/yellow will be saved for
the next time you start muggle. You can define different commands in both view *Music browser*
and *Collection browser*.

\subsection browse Music browser

By default, Muggle starts in the *Music browser* display at the place where you left it 
last time. This browser displays the music library according to a search order, e.g. 
according to artists / albums / tracks or genre / year / track. These search orders are 
currently fixed in the code, but the objective is to make them editable by the user on the 
OSD. Browsing these search orders is done using Up/Down/Left/Right keys. To display the 
contents of a currently selected selection, press Ok. To return to the parent selection 
press Back.

A set of commands can be displayed with the Blue key on the remote control. A new menu 
will open and show the commands explained below. Remember that pressing Red, Green or 
Yellow will make these keys execute the command currently highlighted by the cursor 
from now on.

Those commands are currently available in the *music browser*:

- Instant Play: instantly play the current selection. This does not enter any collection.

- Add to 'play': add the current selection to the default collection. After the first 
start of Muggle, the default collection is 'play'

- Remove from 'play': remove the current selection from the default collection. If 
there are more than one instances of a specific track in the collection, they are all 
removed.

- Collections: switch to the collection view

- Select search order: select another search order

- Export tracklist: generate a file X.m3u containing all tracks from the current selection

- External commands: whatever you define

By default, the red key adds the currently selected collection to the default collection. 
The green key instantly plays the currently selected collection. The yellow key toggles
between the *Music browser* and the *Collection browser*. Thus, if you want to play an
album, browse to it and press green. Remember that you can redefine commands executed by 
Red, Green and Yellow by pressing them while displaying the command list.

\subsection collections Collection browser

The *Collection browser* displays a list of available collections. Browse the list with 
Up/Down and display the collection contents with Ok. Returning to the collection list 
is done by pressing Back. One of the collections (the one called "play" when you start
up Muggle for the first time) is marked with a "->" in front of the name, meaning that
it is the default collection. Whenever you add or remove selections, this default 
collection is the current target, meaning that selections will be added/removed 
to/from this collection.

At the bottom of the list, the entry "Create collection" is displayed. Entering it with 
the right key will make the editor appear on the second half of the line and using the 
keys Up/Down/Left/Right you can enter the name of the new collection. Pressing Ok will 
terminate the editing process and add the new collection to the list. 

Just like with the *music browser*, a set of commands can be displayed with the Blue 
key on the remote control. 

Those commands are currently available in the list of collections. Depending on the
current selection, not all of them are available:

- Instant play: See *music browser*

- Add to 'play': See *music browser*

- Remove from 'play': See *music browser*. Not available when the cursor is on the default collection.

- Remove all entries from 'play': Only available when the cursor is on the default collection.

- Search: switch to the *music browser*

- Set default collection to 'X': as it says.

- Delete collection: Not available for the default collection and for the 'play' collection.

- Export track list: See *music browser*

- External commands: whatever you define

Note that you cannot only add to/remove from collections in the *music browser*.
Rather, also collections can be added/removed. The reason is that - as explained 
above - a collection is also a selection. So everything that can be done with
selections can also be done with collections. An example: if you want to give a
party, you could create a new collection "Party". Now, steer your cursor to the 
collection entitled "Lounge music" and select add. Then go to "Pop 80s" and add 
again. Finally, go to "Dance classics" and add. Now you have created a collection 
"Party" from three already existing collections. To continue this example, let us 
assume that one of your guests has a personal dislike against "Modern Talking". 
Switch to the browser view, go to the artist selection of "Modern Talking" and 
select "Remove". Now all tracks written by Modern Talking will be removed from 
your "Party" collection.

Please note that "Remove" means removing from the default collection. "Delete" will 
delete a collection.

It is possible that a collection holds the same track several times if you add it 
several times. However when you remove that track, all of its occurrences will be removed.

The remote buttons Play, Pause, Stop are also supported while muggle displays its 
OSD. If Stop is pressed, muggle first stops playing what was started by Instant 
Play. Muggle will then continue playing the 'play' collection. A second Stop will 
stop playing the 'play' collection.

*/