mpg123 (1)

SYNOPSIS

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 ... | -

DESCRIPTION

mpg123 reads one or more file\^ s (or standard input if ``-'' is specified) or URL\^ s 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.

OPTIONS

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 occurs.

-s , -\^-stdout

The decoded audio samples are written to standard output, 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 (headerless) linear PCM audio data, 16 bit, stereo, host byte order.

-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 , -\^-single1

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 , -\^-4to1

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 buffering 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 --mono.

-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 option.

-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 combined 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 standard 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 recognized).

-z , -\^-shuffle

Shuffle play. Randomly shuffles the files specified on the command line and in the list file.

--stereo

Force stereo output

--reopen

Forces reopen of the audiodevice after ever song

--8bit

Forces 8bit output

-Z , --random

Full random play