1mpg123(1) General Commands Manual mpg123(1)
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6 mpg123 - play audio MPEG 1.0/2.0/2.5 stream (layers 1, 2 and 3)
7
9 mpg123 [ options ] file-or-URL...
10
12 mpg123 reads one or more files (or standard input if ``-'' is speci‐
13 fied) or URLs and plays them on the audio device (default) or outputs
14 them to stdout. file/URL is assumed to be an MPEG audio bit stream.
15
17 The following operands are supported:
18 file(s) The path name(s) of one or more input files. They must be
20 valid MPEG-1.0/2.0/2.5 audio layer 1, 2 or 3 bit streams. If a
21 dash ``-'' is specified, MPEG data will be read from the stan‐
22 dard input. Furthermore, any name starting with ``http://'' is
23 recognized as URL (see next section).
24
26 mpg123 options may be either the traditional POSIX one letter options,
27 or the GNU style long options. POSIX style options start with a single
28 ``-'', while GNU long options start with ``--''. Option arguments (if
29 needed) follow separated by whitespace (not ``=''). Note that some
30 options can be absent from your installation when disabled in the build
31 process.
32
34 -k num, --skip num
35 Skip first num frames. By default the decoding starts at the
36 first frame.
37 -n num, --frames num
39 Decode only num frames. By default the complete stream is
40 decoded.
41 --fuzzy
43 Enable fuzzy seeks (guessing byte offsets or using approximate
44 seek points from Xing TOC). Without that, seeks need a first
45 scan through the file before they can jump at positions. You
46 can decide here: sample-accurate operation with gapless features
47 or faster (fuzzy) seeking.
48 -y, --no-resync
50 Do NOT try to resync and continue decoding if an error occurs in
51 the input file. Normally, mpg123 tries to keep the playback
52 alive at all costs, including skipping invalid material and
53 searching new header when something goes wrong. With this
54 switch you can make it bail out on data errors (and perhaps
55 spare your ears a bad time). Note that this switch has been
56 renamed from --resync. The old name still works, but is not
57 advertised or recommened to use (subject to removal in future).
58 --resync-limit bytes
60 Set number of bytes to search for valid MPEG data once lost in
61 stream; <0 means search whole stream. If you know there are
62 huge chunks of invalid data in your files... here is your ham‐
63 mer. Note: Only since version 1.14 this also increases the
64 amount of junk skipped on beginning.
65 -p URL | none, --proxy URL | none
67 The specified proxy will be used for HTTP requests. It should
68 be specified as full URL (``http://host.domain:port/''), but the
69 ``http://'' prefix, the port number and the trailing slash are
70 optional (the default port is 80). Specifying none means not to
71 use any proxy, and to retrieve files directly from the respec‐
72 tive servers. See also the ``HTTP SUPPORT'' section.
73 -u auth, --auth auth
75 HTTP authentication to use when recieving files via HTTP. The
76 format used is user:password.
77 --ignore-mime
79 Ignore MIME types given by HTTP server. If you know better and
80 want mpg123 to decode something the server thinks is image/png,
81 then just do it.
82 --no-seekbuffer
84 Disable the default micro-buffering of non-seekable streams that
85 gives the parser a safer footing.
86 -@ file, --list file
88 Read filenames and/or URLs of MPEG audio streams from the speci‐
89 fied file in addition to the ones specified on the command line
90 (if any). Note that file can be either an ordinary file, a dash
91 ``-'' to indicate that a list of filenames/URLs is to be read
92 from the standard input, or an URL pointing to a an appropriate
93 list file. Note: only one -@ option can be used (if more than
94 one is specified, only the last one will be recognized).
95 -l n, --listentry n
97 Of the playlist, play specified entry only. n is the number of
98 entry starting at 1. A value of 0 is the default and means
99 playling the whole list, a negative value means showing of the
100 list of titles with their numbers...
101 --continue
103 Enable playlist continuation mode. This changes frame skipping
104 to apply only to the first track and also continues to play fol‐
105 lowing tracks in playlist after the selected one. Also, the
106 option to play a number of frames only applies to the whole
107 playlist. Basically, this tries to treat the playlist more like
108 one big stream (like, an audio book). The current track number
109 in list (1-based) and frame number (0-based) are printed at exit
110 (useful if you interrupted playback and want to continue later).
111 Note that the continuation info is printed to standard output
112 unless the switch for piping audio data to standard out is used.
113 Also, it really makes sense to work with actual playlist files
114 instead of lists of file names as arguments, to keep track posi‐
115 tions consistent.
116 --loop times
118 for looping track(s) a certain number of times, < 0 means infi‐
119 nite loop (not with --random!).
120 --keep-open
122 For remote control mode: Keep loaded file open after reaching
123 end.
124 --timeout seconds
126 Timeout in (integer) seconds before declaring a stream dead (if
127 <= 0, wait forever).
128 -z, --shuffle
130 Shuffle play. Randomly shuffles the order of files specified on
131 the command line, or in the list file.
132 -Z, --random
134 Continuous random play. Keeps picking a random file from the
135 command line or the play list. Unlike shuffle play above, ran‐
136 dom play never ends, and plays individual songs more than once.
137 --no-icy-meta
139 Do not accept ICY meta data.
140 -i, --index
142 Index / scan through the track before playback. This fills the
143 index table for seeking (if enabled in libmpg123) and may make
144 the operating system cache the file contents for smoother oper‐
145 ating on playback.
146 --index-size size
148 Set the number of entries in the seek frame index table.
149 --preframes num
151 Set the number of frames to be read as lead-in before a seeked-
152 to position. This serves to fill the layer 3 bit reservoir,
153 which is needed to faithfully reproduce a certain sample at a
154 certain position. Note that for layer 3, a minimum of 1 is
155 enforced (because of frame overlap), and for layer 1 and 2, this
156 is limited to 2 (no bit reservoir in that case, but engine spin-
157 up anyway).
158
161 -o module, --output module
162 Select audio output module. You can provide a comma-separated
163 list to use the first one that works.
164 --list-modules
166 List the available modules.
167 -a dev, --audiodevice dev
169 Specify the audio device to use. The default is system-depen‐
170 dent (usually /dev/audio or /dev/dsp). Use this option if you
171 have multiple audio devices and the default is not what you
172 want.
173 -s, --stdout
175 The decoded audio samples are written to standard output,
176 instead of playing them through the audio device. This option
177 must be used if your audio hardware is not supported by mpg123.
178 The output format per default is raw (headerless) linear PCM
179 audio data, 16 bit, stereo, host byte order (you can force mono
180 or 8bit).
181 -O file, --outfile
183 Write raw output into a file (instead of simply redirecting
184 standard output to a file with the shell).
185 -w file, --wav
187 Write output as WAV file. This will cause the MPEG stream to be
188 decoded and saved as file file , or standard output if - is used
189 as file name. You can also use --au and --cdr for AU and CDR
190 format, respectively. Note that WAV/AU writing to non-seekable
191 files, or redirected stdout, needs some thought. Since 1.16.0,
192 the logic changed to writing the header with the first actual
193 data. This avoids spurious WAV headers in a pipe, for example.
194 The result of decoding nothing to WAV/AU is a file consisting
195 just of the header when it is seekable and really nothing when
196 not (not even a header). Correctly writing data with prophetic
197 headers to stdout is no easy business.
198 --au file
200 Does not play the MPEG file but writes it to file in SUN audio
201 format. If - is used as the filename, the AU file is written to
202 stdout. See paragraph about WAV writing for header fun with non-
203 seekable streams.
204 --cdr file
206 Does not play the MPEG file but writes it to file as a CDR file.
207 If - is used as the filename, the CDR file is written to stdout.
208 --reopen
210 Forces reopen of the audiodevice after ever song
211 --cpu decoder-type
213 Selects a certain decoder (optimized for specific CPU), for
214 example i586 or MMX. The list of available decoders can vary;
215 depending on the build and what your CPU supports. This options
216 is only availabe when the build actually includes several opti‐
217 mized decoders.
218 --test-cpu
220 Tests your CPU and prints a list of possible choices for --cpu.
221 --list-cpu
223 Lists all available decoder choices, regardless of support by
224 your CPU.
225 -g gain, --gain gain
227 [DEPRECATED] Set audio hardware output gain (default: don't
228 change). The unit of the gain value is hardware and output mod‐
229 ule dependent. (This parameter is only provided for backwards
230 compatibility and may be removed in the future without prior
231 notice. Use the audio player for playing and a mixer app for
232 mixing, UNIX style!)
233 -f factor, --scale factor
235 Change scale factor (default: 32768).
236 --rva-mix, --rva-radio
238 Enable RVA (relative volume adjustment) using the values stored
239 for ReplayGain radio mode / mix mode with all tracks roughly
240 equal loudness. The first valid information found in ID3V2 Tags
241 (Comment named RVA or the RVA2 frame) or ReplayGain header in
242 Lame/Info Tag is used.
243 --rva-album, --rva-audiophile
245 Enable RVA (relative volume adjustment) using the values stored
246 for ReplayGain audiophile mode / album mode with usually the
247 effect of adjusting album loudness but keeping relative loudness
248 inside album. The first valid information found in ID3V2 Tags
249 (Comment named RVA_ALBUM or the RVA2 frame) or ReplayGain header
250 in Lame/Info Tag is used.
251 -0, --single0; -1, --single1
253 Decode only channel 0 (left) or channel 1 (right), respectively.
254 These options are available for stereo MPEG streams only.
255 -m, --mono, --mix, --singlemix
257 Mix both channels / decode mono. It takes less CPU time than
258 full stereo decoding.
259 --stereo
261 Force stereo output
262 -r rate, --rate rate
264 Set sample rate (default: automatic). You may want to change
265 this if you need a constant bitrate independent of the mpeg
266 stream rate. mpg123 automagically converts the rate. You should
267 then combine this with --stereo or --mono.
268 -2, --2to1; -4, --4to1
270 Performs a downsampling of ratio 2:1 (22 kHz) or 4:1 (11 kHz) on
271 the output stream, respectively. Saves some CPU cycles, but at
272 least the 4:1 ratio sounds ugly.
273 --pitch value
275 Set hardware pitch (speedup/down, 0 is neutral; 0.05 is 5%).
276 This changes the output sampling rate, so it only works in the
277 range your audio system/hardware supports.
278 --8bit Forces 8bit output
280 --float
282 Forces f32 encoding
283 -e enc, --encoding enc
285 Choose output sample encoding. Possible values look like f32
286 (32-bit floating point), s32 (32-bit signed integer), u32
287 (32-bit unsigned integer) and the variants with different num‐
288 bers of bits (s24, u24, s16, u16, s8, u8) and also special vari‐
289 ants like ulaw and alaw 8-bit. See the output of mpg123's
290 longhelp for actually available encodings.
291 -d n, --doublespeed n
293 Only play every n'th frame. This will cause the MPEG stream to
294 be played n times faster, which can be used for special effects.
295 Can also be combined with the --halfspeed option to play 3 out
296 of 4 frames etc. Don't expect great sound quality when using
297 this option.
298 -h n, --halfspeed n
300 Play each frame n times. This will cause the MPEG stream to be
301 played at 1/n'th speed (n times slower), which can be used for
302 special effects. Can also be combined with the --doublespeed
303 option to double every third frame or things like that. Don't
304 expect great sound quality when using this option.
305 -E file, --equalizer
307 Enables equalization, taken from file. The file needs to con‐
308 tain 32 lines of data, additional comment lines may be prefixed
309 with #. Each data line consists of two floating-point entries,
310 separated by whitespace. They specify the multipliers for left
311 and right channel of a certain frequency band, respectively.
312 The first line corresponds to the lowest, the 32nd to the high‐
313 est frequency band. Note that you can control the equalizer
314 interactively with the generic control interface.
315 --gapless
317 Enable code that cuts (junk) samples at beginning and end of
318 tracks, enabling gapless transitions between MPEG files when
319 encoder padding and codec delays would prevent it. This is
320 enabled per default beginning with mpg123 version 1.0.0 .
321 --no-gapless
323 Disable the gapless code. That gives you MP3 decodings that
324 include encoder delay and padding plus mpg123's decoder delay.
325 --no-infoframe
327 Do not parse the Xing/Lame/VBR/Info frame, decode it instead
328 just like a stupid old MP3 hardware player. This implies dis‐
329 abling of gapless playback as the necessary information is in
330 said metadata frame.
331 -D n, --delay n
333 Insert a delay of n seconds before each track.
334 -o h, --headphones
336 Direct audio output to the headphone connector (some hardware
337 only; AIX, HP, SUN).
338 -o s, --speaker
340 Direct audio output to the speaker (some hardware only; AIX,
341 HP, SUN).
342 -o l, --lineout
344 Direct audio output to the line-out connector (some hardware
345 only; AIX, HP, SUN).
346 -b size, --buffer size
348 Use an audio output buffer of size Kbytes. This is useful to
349 bypass short periods of heavy system activity, which would nor‐
350 mally cause the audio output to be interrupted. You should
351 specify a buffer size of at least 1024 (i.e. 1 Mb, which equals
352 about 6 seconds of audio data) or more; less than about 300 does
353 not make much sense. The default is 0, which turns buffering
354 off.
355 --preload fraction
357 Wait for the buffer to be filled to fraction before starting
358 playback (fraction between 0 and 1). You can tune this pre‐
359 buffering to either get faster sound to your ears or safer unin‐
360 terrupted web radio. Default is 0.2 (wait for 20 % of buffer to
361 be full, changed from 1 in version 1.23).
362 --devbuffer seconds
364 Set device buffer in seconds; <= 0 means default value. This is
365 the small buffer between the application and the audio backend,
366 possibly directly related to hardware buffers.
367 --smooth
369 Keep buffer over track boundaries -- meaning, do not empty the
370 buffer between tracks for possibly some added smoothness.
371
374 -t, --test
375 Test mode. The audio stream is decoded, but no output occurs.
376 -c, --check
378 Check for filter range violations (clipping), and report them
379 for each frame if any occur.
380 -v, --verbose
382 Increase the verbosity level. For example, displays the frame
383 numbers during decoding.
384 -q, --quiet
386 Quiet. Suppress diagnostic messages.
387 -C, --control
389 Enable terminal control keys. This is enabled automatically if a
390 terminal is detected. By default use 's' or the space bar to
391 stop/restart (pause, unpause) playback, 'f' to jump forward to
392 the next song, 'b' to jump back to the beginning of the song,
393 ',' to rewind, '.' to fast forward, and 'q' to quit. Type 'h'
394 for a full list of available controls.
395 --no-control
397 Disable terminal control even if terminal is detected.
398 --title
400 In an xterm, rxvt, screen, iris-ansi (compatible, TERM environ‐
401 ment variable is examined), change the window's title to the
402 name of song currently playing.
403 --name name
405 Set the name of this instance, possibly used in various places.
406 This sets the client name for JACK output.
407 --long-tag
409 Display ID3 tag info always in long format with one line per
410 item (artist, title, ...)
411 --utf8 Regardless of environment, print metadata in UTF-8 (otherwise,
413 when not using UTF-8 locale, you'll get ASCII stripdown).
414 -R, --remote
416 Activate generic control interface. mpg123 will then read and
417 execute commands from stdin. Basic usage is ``load <filename> ''
418 to play some file and the obvious ``pause'', ``command. ``jump
419 <frame>'' will jump/seek to a given point (MPEG frame number).
420 Issue ``help'' to get a full list of commands and syntax.
421 --remote-err
423 Print responses for generic control mode to standard error, not
424 standard out. This is automatically triggered when using -s N.
425 --fifo path
427 Create a fifo / named pipe on the given path and use that for
428 reading commands instead of standard input.
429 --aggressive
431 Tries to get higher priority
432 -T, --realtime
434 Tries to gain realtime priority. This option usually requires
435 root privileges to have any effect.
436 -?, --help
438 Shows short usage instructions.
439 --longhelp
441 Shows long usage instructions.
442 --version
444 Print the version string.
445
447 In addition to reading MPEG audio streams from ordinary files and from
448 the standard input, mpg123 supports retrieval of MPEG audio files or
449 playlists via the HTTP protocol, which is used in the World Wide Web
450 (WWW). Such files are specified using a so-called URL, which starts
451 with ``http://''. When a file with that prefix is encountered, mpg123
452 attempts to open an HTTP connection to the server in order to retrieve
453 that file to decode and play it.
454 It is often useful to retrieve files through a WWW cache or so-called
456 proxy. To accomplish this, mpg123 examines the environment for vari‐
457 ables named MP3_HTTP_PROXY, http_proxy and HTTP_PROXY, in this order.
458 The value of the first one that is set will be used as proxy specifica‐
459 tion. To override this, you can use the -p command line option (see
460 the ``OPTIONS'' section). Specifying -p none will enforce contacting
461 the server directly without using any proxy, even if one of the above
462 environment variables is set.
463 Note that, in order to play MPEG audio files from a WWW server, it is
465 necessary that the connection to that server is fast enough. For exam‐
466 ple, a 128 kbit/s MPEG file requires the network connection to be at
467 least 128 kbit/s (16 kbyte/s) plus protocol overhead. If you suffer
468 from short network outages, you should try the -b option (buffer) to
469 bypass such outages. If your network connection is generally not fast
470 enough to retrieve MPEG audio files in realtime, you can first download
471 the files to your local harddisk (e.g. using wget(1)) and then play
472 them from there.
473 If authentication is needed to access the file it can be specified with
475 the -u user:pass.
476
478 When in terminal control mode, you can quit via pressing the q key,
479 while any time you can abort mpg123 by pressing Ctrl-C. If not in ter‐
480 minal control mode, this will skip to the next file (if any). If you
481 want to abort playing immediately in that case, press Ctrl-C twice in
482 short succession (within about one second).
483 Note that the result of quitting mpg123 pressing Ctrl-C might not be
485 audible immediately, due to audio data buffering in the audio device.
486 This delay is system dependent, but it is usually not more than one or
487 two seconds.
488
491 In verbose mode, mpg123 updates a line with various information center‐
492 ing around the current playback position. On any decent terminal, the
493 line also works as a progress bar in the current file by reversing
494 video for a fraction of the line according to the current position. An
495 example for a full line is this:
496 > 0291+0955 00:01.68+00:28.22 [00:05.30] mix 100=085 192 kb/s
498 576 B acc 18 clip p+0.014
499 The information consists of, in order:
501 > single-character playback state (``>'' for playing, ``='' for
503 pausing/looping, ``_'' for stopped)
504 0291+0955
506 current frame offset and number of remaining frames after the
507 plus sign
508 00:01.68+00:28.22
510 current position from and remaining time in human terms (hours,
511 minutes, seconds)
512 [00:05.30]
514 fill of the output buffer in terms of playback time, if the buf‐
515 fer is enabled
516 mix selected RVA mode (possible values: mix, alb (album), and ---
518 (neutral, off))
519 100=085
521 set volume and the RVA-modified effective volume after the equal
522 sign
523 192 kb/s
525 current bitrate
526 576 B size of current frame in bytes
528 acc if positions are accurate, possible values are ``acc'' for accu‐
530 rate positions or ``fuz'' for fuzzy (with guessed byte offsets
531 using mean frame size)
532 18 clip
534 amount of clipped samples, non-zero only if decoder reports that
535 (generic does, some optimized ones not)
536 p+0.014
538 pitch change (increased/decreased playback sampling rate on user
539 request)
540
543 MPEG audio decoding requires a good deal of CPU performance, especially
544 layer-3. To decode it in realtime, you should have at least an
545 i486DX4, Pentium, Alpha, SuperSparc or equivalent processor. You can
546 also use the -m option to decode mono only, which reduces the CPU load
547 somewhat for layer-3 streams. See also the -2 and -4 options.
548 If everything else fails, have mpg123 decode to a file and then use an
550 appropriate utility to play that file with less CPU load. Most proba‐
551 bly you can configure mpg123 to produce a format suitable for your
552 audio device (see above about encodings and sampling rates).
553 If your system is generally fast enough to decode in realtime, but
555 there are sometimes periods of heavy system load (such as cronjobs,
556 users logging in remotely, starting of ``big'' programs etc.) causing
557 the audio output to be interrupted, then you should use the -b option
558 to use a buffer of reasonable size (at least 1000 Kbytes).
559
561 Mostly MPEG-1 layer 2 and 3 are tested in real life. Please report any
562 issues and provide test files to help fixing them.
563 No CRC error checking is performed.
565 Some platforms lack audio hardware support; you may be able to use the
567 -s switch to feed the decoded data to a program that can play it on
568 your audio device.
569
571 Maintainer:
572 Thomas Orgis <maintainer@mpg123.org>, <thomas@orgis.org>
573 Original Creator:
575 Michael Hipp
576 Uses code or ideas from various people, see the AUTHORS file accompany‐
578 ing the source code.
579
581 mpg123 is licensed under the GNU Lesser/Library General Public License,
582 LGPL, version 2.1 .
583
585 http://www.mpg123.org
586 http://sourceforge.net/projects/mpg123
587 29 Feb 2016 mpg123(1)