Presented by Alex Rudnick & Martin Robinson on November 16, 2002
Table of Contents
- 1. History
- 1.1. Overview
- 1.2. Some Silly Dates
- 2. Hardware Considerations
- 2.1. Sound
- 3. Multimedia Utilities
- 3.1. Music
- 3.1.1. amp
- 3.1.2. mpg123
- 3.1.3. mpg321
- 3.1.4. xmms
- 3.1.5. Ogg Vorbis Tools
- 3.2. Video
- 3.3. Tracked Modules
- 3.4. CD Ripping
- 3.1. Music
- 4. Resources
1. History
1.1. Overview
In the past, the use of multimedia in Linux was hampered by the
rarity of hardware accelerated XFree86 servers and finicky ISAPNP
configuration. Full motion video software lacked the codec support
that other operating systems enjoyed. The permeation of quality audio
decoders on the platform, though, was well on its way.
As the accelerated XFree86 server and the release of DVD movies became
more common, Linux became a usable platform for high quality multimedia
video.
1.2. Some Silly Dates
| March | 1996 | Oldest date in isapnptool’s changelog |
| September | 1996 | O’Reilly publishes Linux Multimedia Guide by Jeff Trante |
| 1997 | Amp, written by Tomislav Uzelac, is the first desktop MP3 decoder | |
| November | 1997 | First X11Amp Beta released |
| January | 2000 | MPAA files lawsuits for DeCSS DMCA violations |
2. Hardware Considerations
Multimedia demands more from computer hardware than many other
computing activities, so there are some general requirements for
having a fulfilling multimedia experience in Linux. Recently, support
for popular hardware in Linux has been common.
2.1. Sound
Most new sound cards have at least basic support in Linux. While
many are supported directly by the kernel, there are several alternative
options including the Advanced Linux Sound Architecture and (a
commercial offering) the Open Sound System.
A sound card capable of 16-bit PCM output will suffice for all but
the most extreme audiophile. Hardware MIDI support is less frequent
for most cards, but utilities like timidity can simulate MIDI devices
in software.
3. Multimedia Utilities
3.1. Music
Linux users have available to them a plethora of programs for use in
playing MP3 audio, which may or may not continue to be the format of
choice for storing gigs upon gigs of perfectly legal backups of your
CD collection. Recently more popular, in light of legal hullabaloo
when Fraunhofer began making demands on royalties for MP3 software,
is the Ogg Vorbis format, which has some excellent software available
as well. We’ll discuss a few interesting options for playback.
3.1.1. amp
amp, with its last release in 1997, was created by Tomislav Uzelac while
he was a graduate student at the University of Zagreb in Croatia.
This is yet a very viable solution for playing MP3 audio files — it is
non-interactive, and Just Works from the commandline. A webpage from
the PlayMedia site refers to amp’s MP3 decoding algorithms as "the
Rolls-Royce of MP3 playback technology." What I like about it is that
it’s very simple, and works nicely in small scripts. amp comes with
Slackware, and there is a Debian package for it in the "non-free"
section; it’s not GPL’d, but the source is available and the author
describes it as "free software". AMP stands for "Advanced Multimedia
Products", which was Uzelac’s company, later absorbed by PlayMedia.
AMP is also the AMP in X11AMP, WinAMP, and MacAMP, which are (or
at one point were) derivative works.
To learn more about Tomislav Uzelac, see
http://www.playmedia.hr/tomislav.htm.
3.1.2. mpg123
mpg123 plays and decodes MP3 audio files, and does it rather well. It’s
generally used for its simplicity, and because it works nicely as a backend
for other programs, some of which work from the commandline, under X, with
ncurses, or from within Emacs. While its source is available, mpg123′s
license does not allow for commercial uses, and as such, it isn’t Free
Software. Take a look at mpg321 for a Free option.
mpg123 can be found at http://www.mpg123.de/.
3.1.3. mpg321
mpg321 is a Free replacement for mpg123, intended to replicate its
functionality and allow people to integrate its code into new projects
without licensing entanglements. It uses the Ogg Vorbis project’s libao,
although as of yet it doesn’t play Ogg files (for that, see ogg123). In
a move that could either be seen as helpful or obnoxious, mpg321′s install
scripts by default create a symlink called mpg123 to the mpg321 binary.
mpg321 lives at http://mpg321.sourceforge.net/.
3.1.4. xmms
xmms stands for X MultiMedia System (formerly known as x11amp), and
is a graphical, modular program, using various plugins to handle
various sorts of media files that you might wish to play. It looks
and feels very much like Winamp, for those familiar with that
particular program. Most significantly, it’s used to play MP3,
although it also supports Ogg. xmms’s plugin system allows new file
formats, output methods, and effects to be added without disturbing
the rest of the program. Particularly entertaining is the "voice
removal" plugin, which comes with xmms. In a recent test, it managed
to nearly completely remove Frank Sinatra’s voice from "The Coffee
Song", allowing for an almost perfect karaoke experience. Success
with this particular plugin varies from vocalist to vocalist.
3.1.5. Ogg Vorbis Tools
Ogg Vorbis is an "open, free" audio codec, free from patents and
royalty problems, with a slick variable quality feature. It probably
deserves its own presentation sometime later. Generally
available are the excellent programs oggenc and ogg123, which encode
and decode .ogg files, respectively. Particularly under Slackware,
these ship as the "oggtools" package, but from vorbis.com, they
can be had as vorbis-tools-1.0.tar.gz. These are not the only
programs available for playing oggs, however — as mentioned earlier,
xmms works nicely, as does Zinf (formerly FreeAMP), apparently.
Various other packages are available, as are shell scripts to
convert your entire MP3 collection into oggs. This is generally
not considered as a good idea, however, as converting from one lossy
format to another format lossy in different ways results in a
cumulative loss of sound quality. The xiph.org folks recommend
keeping one’s MP3s (or just re-encoding straight from the CDs
to Ogg) and encoding new music with oggenc, as many players can handle
both formats. xmms supports Ogg Vorbis with no modification, and
oggenc and ogg123 are very easy to use.
With great alacrity (and For Great Justice), take a look at:
3.2. Video
Video is generally the last mile in Linux multimedia. Most hardware
acceleration still requires a fair amount of effort, although the most
popular new cards are well supported. Nvidia releases a closed source
accelerated driver for XFree86 (Linux only), while the now-defunct 3DFX’s
line of Voodoo cards and ATI’s Radeon line have DRI (Direct Rendering
Infrastructure) support in the Linux kernel.
Full motion video utilities can display hardware accelerated output
through the X-Video (Xv) extensions available in XFree86 4.X. X-Video
allows images to be displayed with quality scaling and filtering using
shared memory segments. To test whether hardware accelerated Xv output
is available, use the xvinfo(1) command.
Example xvinfo(1) output
$ xvinfo
X-Video Extension version 2.2
screen #0
3.3. Tracked Modules
Xmp, the Extended Module Player, is a tracked module player which has
support for a multitude of tracked module formats including XM, S3M,
MOD, IT, and many others. If you have GUS or SoundBlaster AWE hardware,
xmp can use the sequencer to play the modules. For more information see
http://xmp.sf.net/.
3.4. CD Ripping
There are quite a few useful utilities for ripping and encoding CD audio.
Among these are cdparanoia, an excellent command-line ripper with error
correction, lame, an MP3 encoder which supports MPEG 1, 2, and 2.5 layer
III encoding, and oggenc, the official Ogg Vorbis encoder. Grip, a GNOME
application can serve as a front end to all these utilities and will
automate the entire ripping/encoding/tagging process involved in archiving
CD audio.