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mpg123 (1)
  • >> mpg123 (1) ( Solaris man: Команды и прикладные программы пользовательского уровня )
  • mpg123 (1) ( Linux man: Команды и прикладные программы пользовательского уровня )
  • Ключ mpg123 обнаружен в базе ключевых слов.
         mpg123 - play audio MPEG 1.0/2.0 file (layers 1, 2 and 3)
         mpg123 [ -tscvqy01m24 ] [ -b size ] [ -k num ] [ -n num ]  [
         -f factor ] [ -r rate ] [ -g gain ] [ -a dev ] [ -o s | -o h
         | -o l ] [ -d n ] [ -h n ] [ -p proxy ] [ -@ file ] file ...
         | URL ... | -
         mpg123 reads one or more files (or standard input  if  ``-''
         is  specified)  or  URLs  and plays them on the audio device
         (default) or outputs them to stdout.  file/URL is assumed to
         be an MPEG-1/2 audio bit stream.
         mpg123 options may  be  either  the  traditional  POSIX  one
         letter  options, or the GNU style long options.  POSIX style
         options start with a single ``-'', while  GNU  long  options
         start with ``--''.
         -t, --test
              Test mode.  The audio stream is decoded, but no  output
         -s, --stdout
              The decoded audio samples are written to standard  out-
              put,  instead of playing them through the audio device.
              This option must be used if your audio hardware is  not
              supported by mpg123.  The output format is raw (header-
              less) linear PCM audio data, 16 bit, stereo, host  byte
         -c, --check
              Check for filter range violations, and report them  for
              each frame if any occur.
         -v, --verbose
              Increase the verbosity level.   For  example,  displays
              the frame numbers during decoding.
         -q, --quiet
              Quiet.  Suppress diagnostic messages.
         -y, --resync
              Try to resync and continue decoding if an error  occurs
              in  the  input  file.  Also try to recover from certain
              broken headers.  Useful if you have a broken MPEG file,
              on  which  mpg123  normally  gives  up  saying `Illegal
              header'.  Be careful:  Broken locations in  MPEG  files
              might  cause  sharp,  loud  pops or clicks, which might
              damage your speakers if played too loud.
         -0, --single0; -1,
              Decode only channel 0  (left)  or  channel  1  (right),
              respectively.   These  options are available for stereo
              MPEG streams only.
         -m, --singlemix
              Mix both channels.  This option is available for stereo
              MPEG layer-3 streams only.  It takes less CPU time than
              full stereo decoding.
         -2, --2to1; -4,
              Performs a downsampling of ratio 2:1 (22  kHz)  or  4:1
              (11 kHz) on the output stream, respectively. Saves some
              CPU cycles, but at least the 4:1 ratio sounds ugly.
         -b size, --buffer size
              Use an audio output buffer of  size  Kbytes.   This  is
              useful   to   bypass  short  periods  of  heavy  system
              activity, which would normally cause the  audio  output
              to  be interrupted. You should specify a buffer size of
              at least 1024 (i.e. 1 Mb, which equals about 6  seconds
              of  audio  data)  or more; less than about 300 does not
              make much sense.  The default is 0, which turns buffer-
              ing off.
         -k num, --skip num
              Skip first num frames.  By default the decoding  starts
              at the first frame.
         -n num, --frames num
              Decode only num frames.  By default the complete stream
              is decoded.
         -f factor, --scale factor
              Change scale factor (default: 32768).
         -r rate, --rate rate
              Set sample rate (default: automatic).  You may want  to
              change  this  if you need a constant bitrate independed
              of the mpeg stream rate. mpg123 automagically  converts
              the rate. You should then combine this with --stereo or
         -g gain, --gain gain
              Set audio hardware output gain (default: don't change).
         -a dev, --audiodevice dev
              Specify the  audio  device  to  use.   The  default  is
              system-dependent (usually /dev/audio or /dev/dsp).  Use
              this option if you have multiple audio devices and  the
              default is not what you want.
         -o s, --speaker
              Direct audio output to the speaker.
         -o h, --headphones
              Direct audio output to the headphone connector.
         -o l, --lineout
              Direct audio output to the line-out connector.
         -d n, --doublespeed n
              Only play every n'th frame.  This will cause  the  MPEG
              stream  to  be played n times faster, which can be used
              for special effects.  Can also  be  combined  with  the
              --halfspeed  option  to  play  3  out  of 4 frames etc.
              Don't  expect  great  sound  quality  when  using  this
         -h n, --halfspeed n
              Play each frame n times.   This  will  cause  the  MPEG
              stream  to  be played at 1/n'th speed (n times slower),
              which can be used for special effects. Can also be com-
              bined  with  the  --doublespeed  option to double every
              third frame or things like that.   Don't  expect  great
              sound quality when using this option.
         -p URL | none, --proxy URL | none
              The specified proxy will be used for HTTP requests.  It
              should      be      specified      as      full     URL
              (``http://host.domain:port/''),  but  the   ``http://''
              prefix,  the  port  number  and  the trailing slash are
              optional (the default port  is  80).   Specifying  none
              means  not  to  use  any  proxy,  and to retrieve files
              directly from the respective  servers.   See  also  the
              ``HTTP SUPPORT'' section.
         -u auth, --auth auth
              HTTP authentication to use  when  recieving  files  via
              HTTP.  The format used is user:password.
         -@ file, --list file
              Read filenames and/or URLs of MPEG audio  streams  from
              the specified file in addition to the ones specified on
              the command line (if  any).   Note  that  file  can  be
              either  an ordinary file, a dash ``-'' to indicate that
              a list of filenames/URLs is to be read from  the  stan-
              dard input, or an URL pointing to a an appropriate list
              file.  Note: only one -@ option can be  used  (if  more
              than one is specified, only the last one will be recog-
         -z, --shuffle
              Shuffle play.  Randomly shuffles the files specified on
              the command line and in the list file.
              Force stereo output
              Forces reopen of the audiodevice after ever song
              Forces 8bit output
         -Z, --random
              Full random play
         The following operands are supported:
         file(s) The path name(s) of one or more input  files.   They
                 must  be  valid MPEG-1/2 audio layer-1, -2 or -3 bit
                 streams.  If a dash ``-'' is  specified,  MPEG  data
                 will  be read from the standard input.  Furthermore,
                 any name starting with ``http://'' is recognized  as
                 URL (see next section).
         In addition to reading  MPEG  audio  streams  from  ordinary
         files and from the standard input, mpg123 supports retrieval
         of MPEG audio files via the HTTP protocol, which is used  in
         the  World Wide Web (WWW).  Such files are specified using a
         so-called URL (universal resource  location),  which  starts
         with  ``http://''.   When a file with that prefix is encoun-
         tered, mpg123 attempts to open an  HTTP  connection  to  the
         server in order to retrieve that file to decode and play it.
         It is often useful to retrieve files through a WWW cache  or
         so-called  proxy.   To  accomplish this, mpg123 examines the
         environment for variables named  MP3_HTTP_PROXY,  http_proxy
         and  HTTP_PROXY,  in this order.  The value of the first one
         that is set will be used as proxy specification.   To  over-
         ride  this,  you can use the -p command line option (see the
         ``OPTIONS'' section).  Specifying -p none will enforce  con-
         tacting the server directly without using any proxy, even if
         one of the above environment variables is set.
         Note that, in order to play MPEG  audio  files  from  a  WWW
         server,  it  is necessary that the connection to that server
         is fast  enough.   For  example,  a  128  kbit/s  MPEG  file
         requires  the  network  connection to be at least 128 kbit/s
         (16 kbyte/s) plus protocol overhead.   If  you  suffer  from
         short network outages, you should try the -b option (buffer)
         to bypass such outages.  If your network connection is  gen-
         erally  not  fast  enough  to  retrieve  MPEG audio files in
         realtime, you can first download the  files  to  your  local
         harddisk (e.g. using lynx(1)) and then play them from there.
         If authentication is needed to access the  file  it  can  be
         specified with the -u user:pass.
         You can abort mpg123 at any time by pressing Ctrl-C.  If you
         are  playing multiple files, this will stop the current file
         and begin playing the next one.  If you want to abort  play-
         ing  immediately instead of skipping to the next file, press
         Ctrl-C twice in short succession (within about one second).
         Note that the result of pressing Ctrl-C might not be audible
         immediately,  due  to audio data buffering in the audio dev-
         ice.  This delay is system dependent, but it is usually  not
         more than one or two seconds.
         lynx(1), sox(1), intro(1)
         MPEG audio decoding requires a good deal of CPU performance,
         especially  layer-3.   To  decode it in realtime, you should
         have at least a Pentium,  Alpha,  SuperSparc  or  equivalent
         processor.  You can also use the -singlemix option to decode
         mono only, which reduces the CPU load somewhat  for  layer-3
         streams.  See also the -2 and -4 options.
         If everything else fails, use the -s  option  to  decode  to
         standard  output,  direct  it  into  a  file and then use an
         appropriate utility to play that file.  You  might  have  to
         use  a tool such as sox(1) to convert the output to an audio
         format suitable for your audio player.
         Also note that mpg123 always generates 16  bit  stereo  data
         (if  one  of  the  -single*  options  is used, two identical
         stereo channels are generated).  If your  hardware  requires
         some  other format, for example 8 bit mono, you also have to
         use a converter such as sox(1).
         If your system is generally fast enough to decode  in  real-
         time,  but  there are sometimes periods of heavy system load
         (such as cronjobs, users logging in  remotely,  starting  of
         ``big'' programs etc.) causing the audio output to be inter-
         rupted, then you should use the -b option to use a buffer of
         at least 1000 Kbytes.
         Known bugs and limitations:
              MPEG-2, Layer 1 and 2 not tested. May not work.  (Layer
              3 should work.)
              Free format streams are not supported.
              Layer-1 support is not heavily tested.
              No CRC error checking is performed.
              There is currently no support for audio hardware on DEC
              Digital  Unix,  Ultrix  and  IBM  AIX, therefore the -s
              option has to be used on those platforms.
         Main author:
              Michael Hipp <>
         Uses code (or at least ideas) from:
              MPEG Software Simulation Group (Base package)
              Philipp Knirsch  <>  (DCT36/manual
              Tobias Bading  <>  (subband  syn-
              Jeff Tsay <> (DCT36)
              Thomas Woerner (SGI Audio)
              Damien  Clermonte  <>   (HP-UX   audio
              Oliver Fromme <>
         Internet references:
         (includes information about the mpg123 mailing list)
         The latest version is also available from here:

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