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You can find more information on ALSA, including an HOWTO, on the web:
  http://www.alsa-project.org

The Advanced Linux Sound Architecture (ALSA) is still in beta, but its
API is stable, so this libmikmod version should work with future
versions of ALSA.

This version of the libmikmod ALSA driver works with either ALSA
versions 0.3.x (for Linux kernels 2.0.x) and 0.4.x (for Linux kernels
2.2.x and later).
The latest versions, 0.5.x and 0.9.x, are currently not supported natively,
although you can use the OSS emulation without problems.

If the sound comes out jerky, you can pass the "buffer=xx" option to the
driver, to tweak the ALSA settings. The default value (if this option is
not used) is 4; the slower your machine is, the greater this value has
to be, but the allowed range is 2 to 16. However, the ALSA generally
finds good settings for your configuration, so I doubt you'll have to
use this option.


>> ENLIGHTENED SOUND DAEMON SPECIFIC INFORMATION (Unix specific)
------------------------------------------------

The Enlightened Sound Daemon (EsounD) is still experimental and may
change a lot until it reaches the 1.0 release. Thus, this libmikmod
version might not work with future versions of EsounD.

You can find more information on EsounD on the web:
  http://www.tux.org/~ricdude/EsounD.html
However, this page is getting very out of date. Recent EsounD work can
be found on the GNOME project:
  http://www.gnome.org/applist/view.php3?name=esound
which not kept up-to-date either...

The version of the libmikmod EsounD driver coincides with the latest
EsounD release available when this version of libmikmod was released;
for the 3.1.10 release, this is EsounD v0.2.23, but libmikmod should
work with any version starting from 0.2.6, although the latest version
is recommended.

Please note that between 0.2.8 and 0.2.12 the server port and the
protocol have changed, thus clients compiled with libesd from 0.2.8 can
not communicate with 0.2.12 (and later) esd, and vice versa.

If the esd daemon dies, libmikmod will try to reconnect every 5 seconds
and every new module, if a module ends. So, you can safely restart esd
and wait 5 seconds, and voila! Sound is back...

If you run esd and a libmikmod application on the same machine,
everything should work fine. However, if there is a real network
connection, synchronization problems can occur.

If sound clicks or gets chopped, then you've likely got a
synchronization problem. Pausing the player for a second should cause
the problem to disappear.  If there's still problems, perhaps your
network is not fast enough. Lowering the playback rate will hopefully
solve the problem.

Also, the performance of the esd is really abominable if the esd
playback frequency can't be divided by the libmikmod playback rate. For
example, runinng a libmikmod application at 42000 Hz with esd at 44100
Hz will sound horrible, and take a lot of CPU time due to resampling.


>> SGI DRIVER SPECIFIC INFORMATION (IRIX specific)
----------------------------------

The SGI audio driver was written by Stephan Kanthak in 1996 and its
author grants to distribute it with the libmikmod package under the same
restrictions as the library.

If you encounter any problems concerning crackles or short stops while
playing, feel free to experiment with the values of the fragsize and
bufsize options of the driver. The default values are 20000 for fragsize
and 40000 for bufsize. Increasing bufsize might result in nonstop sound
on slow machines, but increases latency of interactive applications. The
value of fragsize should be set to about half of bufsize in most cases
and needs to be increased only if you own a very slow SGI.

Common problems

- libmikmod does not compile on my SGI?
  First check out whether you have the SGI audio library (libaudio) or
  not. If the audio library is missing you should upgrade to IRIX 5.3 or
  newer and you will obtain the media development package automatically
  with it. If you have the audio library installed, check out if it is
  in the linker path.

  Also, the audio API has been extended in recent IRIX releases (6.4 and
  later). The older API used by libmikmod is supposed to be still supported,
  please drop me a note if it is not on your IRIX release.

- Sound is _very_ noisy?
  Change sample size to 16 bits.

- Sound crackles or stops temporarily?
  Try to increase the value of the fragsize driver option (default value
  is 20000). Switch to mono mode if necessary.

- libmikmod applications only react very slowly?
  This is a typical effect on SGI machines because the audio library
  sets up an internal buffer that seems to be quite large on many
  installations. Try to decrease the bufsize driver option (default
  value is 40000).

How to contact the driver author:
Stephan Kanthak <[e-mail]>
Please cc: me (miod), just in case.


>> SUNOS, SOLARIS, NETBSD AND OPENBSD DRIVER SPECIFIC INFORMATION
-----------------------------------------------------------------

The above mentioned systems use the same interface to the audio device.
The libmikmod driver for this interface is the Sun driver. It was coded
by Valtteri Vuorikoski <[e-mail]> and updated to libmikmod 3 by Tor
Norbye <[e-mail]>, and has been modified to work under NetBSD
and OpenBSD by the current maintainer.

This driver works with old sound hardware using 8 KHz mono ulaw, and
with modern hardware using pcm mono or stereo at any frequency. If your
settings aren't supported by the audio device, sound initialization will
fail. Refer to the audio(7) man page under SunOS/Solaris and the
audio(4) man page under NetBSD/OpenBSD for more details on your audio
hardware and its capabilities.

On Sun workstations, you might be interested in passing the "headphone"
option to the driver to force output on the headphones, since plugging
the headphones is not enough.

If you run NetBSD or OpenBSD, the driver does not support the headphone
and speaker parameters, but you can achieve the same effect with
audioctl(1), for example:
  audioctl -w play.port=1
will select the speaker, while a value of 2 would have selected the
headphone.

If sound is jerky, you can pass the "buffer=xx" option to the driver to
increase its internal buffer size. The default value (when this option
is not used) is 12; the slower your machine, the greater this value has
to be, in the range 7-17.

If you can't get libmikmod to work with your hardware, you can use its
raw disk writer driver, in 8 bit mono 8 kHz, and send the music.raw file
to /dev/audio with sox, using the following command line:
    sox -t raw -c 1 -r 8000 -u -b music.raw -t raw -U -r 8000 \
        -c 1 -b /dev/audio
(or use the piped output driver with this command line)

Or if you played in 16 bit stereo, you can convert the file to a .au
file:
  audioconvert -o music.au -f sun \
               -i rate=44.1k,channels=stereo,encoding=linear16 music.raw
and play the file:
    audioplay -p headphone -v 10 music.au


>> SAM9407 DRIVER SPECIFIC INFORMATION (Linux specific)
--------------------------------------

The SAM9407 driver provides an OSS-compatible driver for the soundcards
based on the sam9407 audio chip (MaxiSound 64 and Terratec EWS, among
others), and provides advanced features such as hardware module
playback.

You can find more information on this driver on the web:
  http://www.anime.net/~sam9407

The version of the libmikmod sam9407 driver coincides with the latest sam9407
driver release available when this version of libmikmod was released; for the
3.1.10 release, this is sam9407 driver v1.0.0.


>> THANKS
---------

I would like to thank everyone who contributed to libmikmod. Their names
are in the AUTHORS file for the significative contributions, but some
other names can be found in the NEWS file. Thanks a lot! Keeping
libmikmod alive wouldn't be much fun without you.


>> LICENSE
----------

The libmikmod sound library is covered by the GNU Library General Public
License as published by the Free Software Fundation (you'll find it in
the file COPYING.LIB); either version 2 of the licence, or (at your
option) any later version.

The GNU Lesser General Public License, version 2.1, in file
COPYING.LESSER, can be considered as a later version of the LGPL, and is
strongly recommended for people who will embed libmikmod in their
application as a shared library.

Parts of the library (in playercode/mdulaw.c) are derived from the files
libst.h and raw.c from an old version of the sox (SOund eXchange)
package written by Lance Norskog and Jef Poskanzer. The following
copyright notice applies to these parts:

   Copyright (C) 1989 by Jef Poskanzer.

   Permission to use, copy, modify, and distribute this software and its
   documentation for any purpose and without fee is hereby granted, provided
   that the above copyright notice appear in all copies and that both that
   copyright notice and this permission notice appear in supporting
   documentation.  This software is provided "as is" without express or
   implied warranty.


>> CONTACT AND DOWNLOAD INFO
----------------------------

* email:
  Please send all your libmikmod related e-mail to me, at:
    [e-mail]

* web:
  libmikmod home page is located at:
    http://mikmod.raphnet.net