libmodplug - the library which was part of the Modplug-xmms project
Web page: http://modplug-xmms.sf.net/

 Based on the ModPlug sound engine by Olivier Lapicque <olivierl@jps.net>
 XMMS plugin by Kenton Varda <temporal@gauge3d.org> (~2002)
 Maintainer is now Konstanty Bialkowski <konstanty@ieee.org> (~2006)

On Wed 14 Aug 2013 the repository was forked / cloned to GitHub.
The current release is libmodplug v0.8.8.5. 

History
-------
Olivier Lapicque, author of Modplug, which is arguably the best quality
MOD-playing software available, has placed his sound rendering code in the
public domain.  This library and plugin is based on that code.

This code was originally part of modplug-xmms, and was split into a library - libmodplug
and the modplug-xmms code. Also since then an example rendering project called modplugplay and
modplug123 were introduced. They are still available on the sourceforge website.

For more information on libmodplug, the library for decoding mod-like music
formats, see libmodplug/README.

Contents
--------
 1. Requirements
 2. Features
 3. Options
 4. Troubleshooting

---------------
1. Requirements
---------------
- POSIX OS (Linux or other unix*)
- XMMS 1.0.0 or higher (only for modplug-xmms plugin).

* This library is only guaranteed to work on Linux.  I have received
  conflicting reports on whether or not it will work on Solaris x86.
  One person reported that the plugin compiled fine with the
  "-fpermissive" compiler flag, which I have added.  Others had far
  more trouble.  Note that a recent change to the library should allow
  it to work on PPC and other big-endian systems.

* Under linux there is also modplugplay contributed, which allows command
 line playing of mod files under Linux. (Available at http://modplug-xmms.sf.net/)

-----------
2. Features
-----------
- Plays 22 different mod formats, including:
    MOD, S3M, XM, IT, 669, AMF (both of them), AMS, DBM, DMF, DSM, FAR,
    MDL, MED, MTM, OKT, PTM, STM, ULT, UMX, MT2, PSM
- Plays zip, rar, gzip, and bzip2 compressed mods.  The following
    extensions are recognized:
    zip:  MDZ,  S3Z,  XMZ,  ITZ
    rar:  MDR,  S3R,  XMR,  ITR
    gzip: MDGZ, S3GZ, XMGZ, ITGZ
   You can also load plain old ZIP, RAR, and GZ files.  If ModPlug finds
   a mod in them, it will play it.
   Note: To play these formats, you need to have the associated
    decompression utilities (unzip, gunzip, unrar) installed.
   Note(2): The format of the mod is NOT determined from the extension on
    compressed mods.  For example, if you zipped a UMX mod and gave it the
    extension MDZ, it would work fine.
- plays timidity's GUS patch files (*.pat):
   a multi sample pat file with n samples can be played with a Frere Jacques 
   canon with n voices.
- plays all types of MIDI files (*.mid):
   uses the timidity .pat files for samples (when available)
   recognizes environment variables:

     MMPAT_PATH_TO_CFG	set to the directory where the file "timidity.cfg" and
      the subdirectory "instruments" can be found,
       default: "/usr/local/share/timidity".
      MMMID_SPEED for experimenting with the mod speed (1 thru 9)
      MMMID_VERBOSE for feedback on the conversion process
      MMMID_DEBUG for sake of completeness, only useful for maintainers

- plays textfiles written in the ABC music notation (*.abc):
   uses the timidity .pat files for samples (when available)
   recognizes environment variables:

      MMPAT_PATH_TO_CFG	set to the directory where the file "timidity.cfg" and
       the subdirectory "instruments" can be found,
       default: "/usr/local/share/timidity".

      MMABC_NO_RANDOM_PICK when not set and the abc file contains multiple songs
       (X:n) the first song to be played will be picked at random another click 
       on the play button advances to the next
       song in the file (or the first when the last song has been
       played), when set it can be 0 (zero) or not numeric
       to let it play all songs in the file, a positive number n to
       let it play the n-th song in the file, a negative number -n to
       let it play the n-th song in the file and advancing to the next
       song when the play button is clicked.

      MMABC_DUMPTRACKS when set it gives diagnostic information on stdout, 
       values can be:

        all - every event is printed
        nonotes - only the control events (looping, breaks etc.) are printed
           any other value prints the control events and every note event
           immediately succeeding the control events.
- Slightly better sound quality than Mikmod.  Vastly superior quality
   over Winamp.
- All XMMS calls are supported except for the band gains on the
   equalizer.  The preamp is supported, but MOD music is not anywhere
   near as cheap to equalize as MP3.  Thus, equalization does is not
   supported in this version.  However, a variable bass boost option
   is available in the configuration dialog (see below).
- Tons of playback options (see below).

----------
3. Options
----------
All of the following items are configurable from the plugin
configuration dialog box.

Sampling rate: Higher is better.  Note that the sound is rendered at a
 higher sampling rate and converted down to increase quality.

Bits per sample: 8-bit or 16-bit sound.  Note that all computations are
 done at 32-bit and converted down to the sampling rate you specify.

Channels: mono/stereo.  Note that all computations are done in stereo.
 If you choose mono, the channels will be mixed.

Resampling: Method used to convert samples to different sampling rates.
 "Nearest" is the fastest setting (but sounds terrible), while
 "8-tap fir" is the best-quality setting.

Noise Reduction: Reduces noise. :)

Fast Playlist Info: When this option is on, names of songs in your
 playlist will load considerably faster, but song lengths will not be
 shown and only MOD, S3M, XM, and IT formats will have their names shown.
 Don't worry, though, because all the data which is skipped will still be
 loaded when you actually play the song.  This should probably always be
 on.

Reverb: A nice reverb effect.  The depth and delay of the reverb can be
 tuned to your liking using the sliders.

Bass boost: Variable bass boost effect.  The "range" slider controls the
 frequency range of the bass boost.  If you increase this value, higher
 frequencies will be boosted, but the overall volume increase will be
 less.  (you can compensate by using the volume slider:)

Surround: Dolby Pro-Logic surround effect.  Depth and delay can be fine
 tuned.

Preamp: A global volume boost.  Note that setting the preamp too high
 will cause clipping (nasty clicks and pops).

Looping: Some mods have loops built-in.  Normally, these loops are
 ignored because otherwise the same mod would play forever.  However,
 you can choose to respect the loops, or even set a number of times to
 follow a loop.

------------------
4. Troubleshooting
------------------

Problem:
 Some of my files load up, but show garbled info in the playlist and/or
 don't play correctly.

Possible cause:
 The mod is in a different format than its file format suggests.
 Modplug-XMMS uses a combination of file extension and contents to figure
 out what format a mod is in, and can be thrown off if a mod is
 incorrectly labeled.

Solution:
 Turning off "fast info" in the configuration may fix the problem.  This
 will cause Modplug-XMMS to detect all basic mod types by content, but
 archive types will still be detected by extension.  If this doesn't
 solve the problem, then you probably have files which are actually
 compressed archives but are not labeled as such.  For example, you may
 have a file "aws_anew.xm" which is actually a ZIP archive.  You will
 have to either unzip these files or rename them to have an extension
 associated with their type.  In the case of a ZIP, you can use any of
 the extensions "ZIP, MDZ, S3Z, XMZ, ITZ".  (Note that these five types
 are all treated exactly the same -- the actual format of the mod is
 detected by contents.)


Problem:
 Everything appears to be working, but no sound is being generated.
 MP3's play just fine.

Possible cause:
 Modplug has a relatively low default volume, and you may just not be
 hearing it.  (Note:  Yes, more that one person has e-mailed me with
 this problem.)

Solution:
 Turn up your volume.  You may wish to do this via the "preamp"
 setting in the ModPlug configuration.  This way, you won't have to
 turn down your volume again when you play an MP3.


Problem:
 You have a mod which is rendered incorrectly by ModPlug-XMMS.

Possible cause:
 This could be our fault. :)

Solution:
 First, test the mod using the Windows version of ModPlug, if you can.
 If it sounds wrong there, then send the mod and a bug report to
 Olivier Lapicque <olivierl@jps.net>.  If the mod plays correctly in
 Windows, however, then the bug is my fault.  In that case, e-mail
 me (Konstanty) <konstanty@ieee.org>. (previously Kenton Varda at 
 <temporal@gauge3d.org>).


Problem:
 I have a problem which is not listed here, or an idea for a cool
 feature.

Solution:
 E-mail me (Konstanty) at <konstanty@ieee.org>.  I would be
 happy to hear any suggestions or problems you have.