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11.2. Sound and video playing

11.2.1. CD playing and copying

The cdp package comes with most distributions and provides cdp or cdplay, a text-based CD player. Desktop managers usually include a graphical tool, such as the gnome-cd player in Gnome, that can be started from a menu.

Be sure to understand the difference between an audio CD and a data CD. You do not have to mount an audio CD into the file system in order to listen to it. This is because the data on such a CD are not Linux file system data; they are accessed and sent to the audio output channel directly, using a CD player program. If your CD is a data CD containing .mp3 files, you will first need to mount it into the file system, and then use one of the programs that we discuss below in order to play the music. How to mount CDs into the file system is explained in Section 7.5.5.

The cdparanoia tool from the package with the same name reads audio directly as data from the CD, without analog conversions, and writes data to a file or pipe in different formats, of which .wav is probably the most popular. Various tools for conversion to other formats, formats, such as .mp3, come with most distributions or are downloadable as separate packages. The GNU project provides several CD playing, ripping and encoding tools, database managers; see the Free Software Directory, Audio section for detailed information.

Audio-CD creation is eased, among many others, with the kaudiocreator tool from the KDE suite. It comes with clear information from the KDE Help Center.

CD burning is covered in general in Section 9.2.2.

11.2.2. Playing music files

11.2.2.1. mp3 files

The popular .mp3 format is widely supported on Linux machines. Most distributions include multiple programs that can play these files. Among many other applications, XMMS, which is presented in the screenshot below, is one of the most wide-spread, partially because it has the same look and feel as the Windows tool.

Figure 11-1. XMMS mp3 player

Also very popular for playing music are AmaroK, a KDE application that is steadily gaining popularity, and MPlayer, which can also play movies.

NoteRestrictions
 

Some distributions don't allow you to play MP3's without modifying your configuration, this is due to license restrictions on the MP3 tools. You might need to install extra software to be able to play your music.

In text mode, you can use the mplayer command:


[tille@octarine ~]$ mplayer /opt/mp3/oriental/*.mp3
MPlayer 1.0pre7-RPM-3.4.2 (C) 2000-2005 MPlayer Team
CPU: Advanced Micro Devices Duron Spitfire (Family: 6, Stepping: 1)
Detected cache-line size is 64 bytes
CPUflags:  MMX: 1 MMX2: 1 3DNow: 1 3DNow2: 1 SSE: 0 SSE2: 0
Playing /opt/oldopt/mp3/oriental/Mazika_Diana-Krozon_Super-Star_Ensani-Ma-
Bansak.mp3.
Cache fill:  1.17% (98304 bytes)    Audio file detected.
Clip info:
Title: Ensani-Ma-Bansak.mp3
Artist: Diana-Krozon
Album: Super-Star
Year:
Comment:
Genre: Unknown
==========================================================================
Opening audio decoder: [mp3lib] MPEG layer-2, layer-3
mpg123: Can't rewind stream by 450 bits!
AUDIO: 44100 Hz, 2 ch, s16le, 160.0 kbit/11.34% (ratio: 20000->176400)
Selected audio codec: [mp3] afm:mp3lib (mp3lib MPEG layer-2, layer-3)
==========================================================================
Checking audio filter chain for 44100Hz/2ch/s16le -> 44100Hz/2ch/s16le...
AF_pre: 44100Hz/2ch/s16le
AO: [oss] 44100Hz 2ch s16le (2 bps)
Building audio filter chain for 44100Hz/2ch/s16le -> 44100Hz/2ch/s16le...
Video: no video
Starting playback...
A: 227.8 (03:23:.1) 1.8% 12%

11.2.2.2. Other formats

It would lead us too far to discuss all possible audio formats and ways to play them. An (incomplete) overview of other common sound playing and manipulating software:

  • Ogg Vorbis: Free audio format: see the GNU audio directory for tools - they might be included in your distribution as well. The format was developed because MP3 is patented.

  • Real audio and video: realplay from RealNetworks.

  • SoX or Sound eXchange: actually a sound converter, comes with th e play program. Plays .wav, . ogg and various other formats, including raw binary formats.

  • Playmidi: a MIDI player, see the GNU directory.

  • AlsaPlayer: from the Advanced Linux Sound Architecture project, see the AlsaPlayer web site.

  • mplayer: plays just about anything, including mp3 files. More info on the MPlayerHQ website.

  • hxplay: supports RealAudio and RealVideo, mp3, mp4 audio, Flash, wav and more, see HelixDNA (not all components of this software are completely free).

  • rhythmbox: based on the GStreamer framework, can play everything supported in GStreamer, which claims to be able to play everything, see the Rhythmbox and GStreamer sites.

Check your system documentation and man pages for particular tools and detailed explanations on how to use them.

NoteI don't have these applications on my system!
 

A lot of the tools and applications discussed in the above sections are optional software. It is possible that such applications are not installed on your system by default, but that you can find them in your distribution as additional packages. It might also very well be that the application that you are looking for is not in your distribution at all. In that case, you need to download it from the application's web site.

11.2.2.3. Volume control

aumix and alsamixer are two common text tools for adjusting audio controls. Use the arrow keys to toggle settings. The alsamixer has a graphical interface when started from the Gnome menu or as gnome-alsamixer from the command line. The kmix tool does the same in KDE.

Regardless of how you choose to listen to music or other sounds, remember that there may be other people who may not be interested in hearing you or your computer. Try to be courteous, especially in office environments. Use a quality head-set, rather than the ones with the small ear pieces. This is better for your ears and causes less distraction for your colleagues.

11.2.3. Recording

Various tools are again available that allow you to record voice and music. For recording voice you can use arecord on the command line:


alexey@russia:~> arecord /var/tmp/myvoice.wav
Recording WAVE '/var/tmp/myvoice.wav' : Unsigned 8 bit, Rate 8000 Hz, Mono
Aborted by signal Interrups...

"Interrupt" means that the application has caught a Ctrl+C. Play the sample using the simple play command.

This is a good test that you can execute prior to testing applications that need voice input, like Voice over IP (VoIP). Keep in mind that the microphone input should be activated. If you don't hear your own voice, check your sound settings. It often happens that the microphone is muted or on verry low volume. This can be easily adjusted using alsamixer or your distribution-specific graphical interface to the sound system.

In KDE you can start the krec utility, Gnome provides the gnome-sound-recorder.