Provided by: sox_14.0.0-5_i386 bug

NAME

       SoX - Sound eXchange, the Swiss Army knife of audio manipulation

DESCRIPTION

       File  types  that  can be determined by a filename extension are listed
       with their names preceded by a dot.

       File types  that  require  an  external  library,  such  as  ffmpeg  or
       libsndfile,  are marked e.g. ‘(ffmpeg)’. File types that can be handled
       by an external library via its pseudo file type  (currently  libsndfile
       or  ffmpeg)  are  marked  e.g.  ‘(also with -t sndfile)’. This might be
       useful if you have a file that doesn’t work with SoX’s  default  format
       readers  and writers, and there’s an external reader or writer for that
       format.

       .raw (also with -t sndfile)
              Raw (headerless) audio files.  The sample rate, sample size, and
              data  encoding  must be given using command-line format options;
              the number of channels defaults to 1.

       .ub, .sb, .uw, .sw, .ul, .al, .lu, .la, .sl (also with -t sndfile)
              These filename extensions serve as shorthand for identifying the
              format of headerless audio files.  Thus, ub, sb, uw, sw, ul, al,
              lu, la and sl indicate a  file  with  a  single  audio  channel,
              sample  rate of 8000 Hz, and samples encoded as ‘unsigned byte’,
              ‘signed byte’, ‘unsigned word’, ‘signed word’,  ‘μ-law’  (byte),
              ‘A-law’ (byte), inverse bit order ‘μ-law’, inverse bit order ‘A-
              law’,  or  ‘signed  long’  respectively.   Command-line   format
              options  can  also  be given to modify the selected format if it
              does not provide an exact match for a particular file.

              Headerless audio files on a SPARC computer are likely to  be  of
              format  ul;  on a Mac, they’re likely to be ub but with a sample
              rate of 11025 or 22050 Hz.

       .8svx (also with -t sndfile)
              Amiga 8SVX musical instrument description format.

       .aiff, .aif (also with -t sndfile)
              AIFF files used on Apple  IIc/IIgs  and  SGI.   Note:  the  AIFF
              format  supports  only  one  SSND  chunk.   It  does not support
              multiple  audio  chunks,  or   the   8SVX   musical   instrument
              description  format.  AIFF files are multimedia archives and can
              have multiple audio and picture chunks.  You may need a separate
              archiver to work with them.

       .aiffc, .aifc (also with -t sndfile)
              AIFF-C  (not  compressed,  linear),  defined in DAVIC 1.4 Part 9
              Annex B.  This format is referred from ARIB  STD-B24,  which  is
              specified  for  Japanese  data broadcasting.  Any private chunks
              are not supported.

              Note: The input file is currently processed as .aiff.

       alsa   ALSA device driver.  This is  a  pseudo-file  type  and  can  be
              optionally compiled into SoX.  Run

                   sox -h

              to see if you have support for this file type.  When this driver
              is used it allows you to open up a ALSA device and configure  it
              to  use  the same data format as passed in to SoX.  It works for
              both playing and recording  audio  files.   When  playing  audio
              files  it  attempts  to  set  up the ALSA driver to use the same
              format as the input file.  It is suggested  to  always  override
              the  output  values  to use the highest quality format your ALSA
              system can handle.  Example:

                   sox infile -t alsa default

       .amr-nb
              Adaptive Multi Rate - Narrow Band speech codec; a  lossy  format
              used  in  3rd generation mobile telephony and defined in 3GPP TS
              26.071 et al.

              AMR-NB audio has a fixed sampling rate of  8  kHz  and  supports
              encoding  to  the  following  bit-rates  (as  selected by the -C
              option): 0 = 4.75 kbit/s, 1 = 5.15 kbit/s, 2 = 5.9 kbit/s,  3  =
              6.7 kbit/s, 4 = 7.4 kbit/s 5 = 7.95 kbit/s, 6 = 10.2 kbit/s, 7 =
              12.2 kbit/s.

              This format in SoX is optional and requires access  to  external
              libraries.  To see if there is support for this format, enter

                   sox -h

              and look for it under the list: SUPPORTED FILE FORMATS.

       .amr-wb
              Adaptive  Multi  Rate  -  Wide Band speech codec; a lossy format
              used in 3rd generation mobile telephony and defined in  3GPP  TS
              26.171 et al.

              AMR-WB  audio  has  a fixed sampling rate of 16 kHz and supports
              encoding to the following  bit-rates  (as  selected  by  the  -C
              option):  0 = 6.6 kbit/s, 1 = 8.85 kbit/s, 2 = 12.65 kbit/s, 3 =
              14.25 kbit/s, 4 = 15.85 kbit/s 5  =  18.25  kbit/s,  6  =  19.85
              kbit/s, 7 = 23.05 kbit/s, 8 = 23.85 kbit/s.

              This  format  in SoX is optional and requires access to external
              libraries.  To see if there is support for this format  on  your
              system, enter

                   sox -h

              and look for it under the list: SUPPORTED FILE FORMATS.

       ao     libao  device  driver.   This  is  a pseudo-file type and can be
              optionally compiled into SoX.  Run

                   sox -h

              to see if you have support for this file type. It works only for
              playing  audio files. It can play to a wide range of devices and
              sound systems. See its documentation for the full range. At  the
              moment  SoX’s  use  of  libao cannot be configured directly; you
              must use libao configuration files.

       .au, .snd (also with -t sndfile)
              Sun Microsystems AU files.  There are many types of AU file; DEC
              has  invented  its  own  with  a different magic number and byte
              order.  SoX can read these files but will not write them.   Some
              .au  files  are  known  to  have  invalid  AU headers; these are
              probably original Sun μ-law 8000 Hz files and can be dealt  with
              using the .ul format (see below).

              It  is  possible to override AU file header information with the
              -r and -c options, in which case SoX will  issue  a  warning  to
              that effect.

       auto   This  format  type name exists for backwards compatibility only.
              If given for an input file it will be silently ignored, if given
              for an output file it will cause SoX to exit with an error.

       .avr   Audio  Visual  Research.  The AVR format is produced by a number
              of commercial packages on the Mac.

       .caf (libsndfile)
              Core Audio File format.

       .cdda, .cdr
              ‘Red Book’ Compact Disc  Digital  Audio.   CDDA  has  two  audio
              channels formatted as 16-bit signed integers at a sample rate of
              44.1 kHz.  The number of (stereo) samples in each CDDA track  is
              always  a multiple of 588 which is why it needs its own handler.

       .cvsd, .cvs
              Continuously Variable  Slope  Delta  modulation.   A  headerless
              format  used  to  compress speech audio for applications such as
              voice mail.  This format is  sometimes  used  with  bit-reversed
              samples - the -X format option can be used to set the bit-order.

       .dat   Text Data files.  These files contain a  textual  representation
              of  the  sample  data.   There is one line at the beginning that
              contains the sample rate.  Subsequent lines contain two  numeric
              data items: the time since the beginning of the first sample and
              the sample value.  Values are normalized so that the maximum and
              minimum  are  1  and -1.  This file format can be used to create
              data files for external programs such as FFT analysers or  graph
              routines.   SoX can also convert a file in this format back into
              one of the other file formats.

       .dvms, .vms
              Used in Germany to compress speech  audio  for  voice  mail.   A
              self-describing variant of cvsd.

       .fap (libsndfile)
              See .paf.

       ffmpeg This  is a pseudo-type that forces ffmpeg to be used. The actual
              file type is deduced from the file name (it cannot  be  used  on
              stdio).  This  pseudo-type depends on SoX having been built with
              optional ffmpeg support. It can  read  a  wide  range  of  audio
              files,  not all of which are documented here, and also the audio
              track of many video files (including  AVI,  WMV  and  MPEG).  At
              present only the first audio track of a file can be read.

       .flac (also with -t sndfile)
              Free  Lossless  Audio  CODEC compressed audio.  FLAC is an open,
              patent-free CODEC designed for compressing music.  It is similar
              to  MP3  and  Ogg  Vorbis,  but  lossless, meaning that audio is
              compressed in FLAC without any loss in quality.

              SoX can decode native FLAC files (.flac) but not Ogg FLAC  files
              (.ogg).  [But see .ogg below for information relating to support
              for Ogg Vorbis files.]

              SoX has basic support for writing FLAC files: it can  encode  to
              native  FLAC  using compression levels 0 to 8.  8 is the default
              compression level and gives the best (but slowest)  compression;
              0  gives  the  least (but fastest) compression.  The compression
              level can be selected using the -C option  (see  above)  with  a
              whole number from 0 to 8.

              FLAC  support  in  SoX  is  optional  and requires optional FLAC
              libraries.  To see if there is support for FLAC run

                   sox -h

              and look for it under the list  of  supported  file  formats  as
              ‘flac’.

       .fssd  An alias for the .ub format.

       .gsm (also with -t sndfile)
              GSM   06.10  Lossy  Speech  Compression.   A  lossy  format  for
              compressing speech which is used  in  the  Global  Standard  for
              Mobile  telecommunications  (GSM).   It’s  good for its purpose,
              shrinking audio data size, but it will introduce lots  of  noise
              when a given audio signal is encoded and decoded multiple times.
              This format is used by some  voice  mail  applications.   It  is
              rather CPU intensive.

              GSM  in  SoX  is optional and requires access to an external GSM
              library.  To see if there is support for GSM run

                   sox -h

              and look for it under the list of supported file formats.

       .hcom  Macintosh HCOM files.  These are  (apparently)  Mac  FSSD  files
              with  some  variant  of  Huffman compression.  The Macintosh has
              wacky file formats and this format  handler  apparently  doesn’t
              handle  all the ones it should.  Mac users will need their usual
              arsenal of file converters to deal with an HCOM  file  on  other
              systems.

       ircam (also with -t sndfile)
              Another name for .sf.

       .ima (also with -t sndfile)
              A  headerless  file  of  IMA  ADPCM audio data. IMA ADPCM claims
              16-bit precision packed into only 4 bits, but in fact sounds  no
              better than .vox.

       .lpc, .lpc10
              LPC-10  is  a  compression  scheme  for  speech developed in the
              United  States.   See   http://www.arl.wustl.edu/~jaf/lpc/   for
              details.   There   is   no  associated  file  format,  so  SoX’s
              implementation is headerless.

       .mat, .mat4, .mat5 (libsndfile)
              Matlab 4.2/5.0 (respectively GNU Octave 2.0/2.1) format (.mat is
              the same as .mat4).

       .m3u   A  playlist format; contains a list of audio files.  See [1] for
              details of this format.

       .maud  An IFF-conforming audio file type, registered by MS  MacroSystem
              Computer  GmbH, published along with the ‘Toccata’ sound-card on
              the Amiga.  Allows 8bit linear, 16bit linear,  A-Law,  μ-law  in
              mono and stereo.

       .mp3, .mp2
              MP3  compressed  audio.   MP3 (MPEG Layer 3) is part of the MPEG
              standards for audio  and  video  compression.   It  is  a  lossy
              compression  format  that  achieves  good compression rates with
              little quality loss.  See also Ogg Vorbis for a similar  format.

              MP3  support in SoX is optional and requires access to either or
              both the external libmad and libmp3lame  libraries.  To  see  if
              there is support for MP3 run

                   sox -h

              and  look  for  it  under  the list of supported file formats as
              ‘mp3’.

       .mp4, .m4a (ffmpeg)
              MP4 compressed  audio.   MP3  (MPEG  4)  is  part  of  the  MPEG
              standards  for  audio  and  video compression.  See mp3 for more
              information.

              MP4 support in SoX  is  optional  and  requires  access  to  the
              external ffmpeg libraries.

       .nist (also with -t sndfile)
              See .sph.

       .ogg, .vorbis
              Ogg  Vorbis compressed audio.  Ogg Vorbis is a open, patent-free
              CODEC designed for compressing music and streaming audio.  It is
              a  lossy  compression  format  (similar  to MP3, VQF & AAC) that
              achieves good compression rates with a minimum amount of quality
              loss.  See also MP3 for a similar format.

              SoX  can decode all types of Ogg Vorbis files, and can encode at
              different compression levels/qualities given as a number from -1
              (highest  compression/lowest quality) to 10 (lowest compression,
              highest quality).  By default the encoding quality  level  is  3
              (which  gives  an encoded rate of approx. 112kbps), but this can
              be changed using the -C option (see above) with a number from -1
              to 10; fractional numbers (e.g.  3.6) are also allowed.

              Decoding  is  somewhat  CPU  intensive  and encoding is very CPU
              intensive.

              Ogg Vorbis in SoX is optional and requires  access  to  external
              Ogg Vorbis libraries.  To see if there is support for Ogg Vorbis
              run

                   sox -h

              and look for it under the list  of  supported  file  formats  as
              ‘vorbis’.

       oss    OSS  /dev/dsp  device driver.  This is a pseudo-file that can be
              optionally compiled into SoX.  Run

                   sox -h

              to see if it is supported. When this driver is  used  it  allows
              you to play and record sounds on supported systems. When playing
              audio files it attempts to set up the OSS driver to use the same
              format as the input file. It is suggested to always override the
              output values to use the highest quality format your OSS  system
              can handle. Example:

                   sox infile -t oss -2 -s /dev/dsp

       .paf, .fap (libsndfile)
              Ensoniq  PARIS file format (big and little-endian respectively).

       .pls   A playlist format; contains a list of audio files.  See [2]  for
              details of this format.

              Note:  SHOUTcast  PLS  relies  on  wget(1) and is only partially
              supported: it’s necessary to specify the  audio  type  manually,
              e.g.

                   play -t mp3 "http://a.server/pls?rn=265&file=filename.pls"

              and  SoX  does  not  know about alternative servers - hit Ctrl-C
              twice in quick succession to quit.

       .prc   Psion Record. Used in  Psion  EPOC  PDAs  (Series  5,  Revo  and
              similar)  for  System alarms and recordings made by the built-in
              Record application.  When writing, SoX defaults to A-law,  which
              is  recommended;  if you must use ADPCM, then use the -i switch.
              The sound quality is poor because Psion Record seems  to  insist
              on  frames  of 800 samples or fewer, so that the ADPCM CODEC has
              to be reset at every 800  frames,  which  causes  the  sound  to
              glitch every tenth of a second.

       .pvf (libsndfile)
              Portable Voice Format.

       .sd2 (libsndfile)
              Sound Designer 2 format.

       .sds (libsndfile)
              MIDI Sample Dump Standard.

       .sf (also with -t sndfile)
              IRCAM    SDIF    (Institut    de   Recherche   et   Coordination
              Acoustique/Musique Sound Description Interchange  Format).  Used
              by  academic  music software such as the CSound package, and the
              MixView sound sample editor.

       .sph, .nist (also with -t sndfile)
              SPHERE (SPeech HEader Resources) is a  file  format  defined  by
              NIST  (National  Institute  of  Standards and Technology) and is
              used with speech audio.  SoX can  read  these  files  when  they
              contain   μ-law  and  PCM  data.   It  will  ignore  any  header
              information that says  the  data  is  compressed  using  shorten
              compression  and  will  treat  the  data as either μ-law or PCM.
              This will allow SoX and the command line shorten program  to  be
              run  together  using pipes to encompasses the data and then pass
              the result to SoX for processing.

       .smp   Turtle Beach SampleVision files.  SMP files are for use with the
              PC-DOS  package  SampleVision  by  Turtle Beach Softworks.  This
              package is for communication  to  several  MIDI  samplers.   All
              sample  rates are supported by the package, although not all are
              supported by the samplers themselves.  Currently loop points are
              ignored.

       .snd   See .au.

       sndfile
              This  is  a  pseudo-type  that forces libsndfile to be used. For
              writing files, the actual file  type  is  then  taken  from  the
              output file name; for reading them, it is deduced from the file.
              This pseudo-type depends on SoX having been built with  optional
              libsndfile support.

       .sndt  SoundTool files. This is an older DOS file format.

       .sou   An alias for the .ub format.

       sunau  Sun  /dev/audio  device  driver.  This is a pseudo-file type and
              can be optionally compiled into SoX.  Run

                   sox -h

              to see if you have support for this file type.  When this driver
              is  used  it  allows  you  to  open up a Sun /dev/audio file and
              configure it to use the same data type as passed in to SoX.   It
              works  for both playing and recording audio files.  When playing
              audio files it attempts to set up the audio driver  to  use  the
              same  format  as  the  input  file.   It  is suggested to always
              override the output values to use  the  highest  quality  format
              your hardware can handle.  Example:

                   sox infile -t sunau -2 -s /dev/audio

              or

                   sox infile -t sunau -U -c 1 /dev/audio

              for older sun equipment.

       .txw   Yamaha  TX-16W  sampler.   A  file format from a Yamaha sampling
              keyboard which  wrote  IBM-PC  format  3.5"  floppies.   Handles
              reading  of files which do not have the sample rate field set to
              one of the expected by  looking  at  some  other  bytes  in  the
              attack/loop  length  fields,  and  defaulting  to  33 kHz if the
              sample rate is still unknown.

       .vms   See .dvms.

       .voc (also with -t sndfile)
              Sound Blaster VOC files.  VOC files are multi-part  and  contain
              silence parts, looping, and different sample rates for different
              chunks.  On input, the silence parts are filled out,  loops  are
              rejected,  and  sample  data with a new sample rate is rejected.
              Silence with a different sample rate is generated appropriately.
              On  output,  silence  is not detected, nor are impossible sample
              rates.  Note, this version now supports playing VOC  files  with
              multiple  blocks and supports playing files containing μ-law and
              A-law samples.

       .vorbis
              See .ogg.

       .vox (also with -t sndfile)
              A headerless file of  Dialogic/OKI  ADPCM  audio  data  commonly
              comes  with  the  extension  .vox.   This  ADPCM data has 12-bit
              precision packed into only 4-bits.

              Note: some early Dialogic hardware does  not  always  reset  the
              ADPCM encoder at the start of each vox file.  This can result in
              clipping and/or DC offset problems when it comes to decoding the
              audio.   Whilst  little  can  be  done  about the clipping, a DC
              offset can be removed by passing the  decoded  audio  through  a
              high-pass filter, e.g.:

                   sox input.vox output.au highpass 10

       .w64 (libsndfile)
              Sonic Foundry’s 64-bit RIFF/WAV format.

       .wav (also with -t sndfile)
              Microsoft .WAV RIFF files.  This is the native audio file format
              of Windows, and widely used for uncompressed audio.

              Normally .wav files have all  formatting  information  in  their
              headers,  and so do not need any format options specified for an
              input file.  If any are, they will override the file header, and
              you will be warned to this effect.  You had better know what you
              are doing! Output format options will cause a format conversion,
              and the .wav will written appropriately.

              SoX  currently can read PCM, μ-law, A-law, MS ADPCM, and IMA (or
              DVI) ADPCM.  It can write all of  these  formats  including  the
              ADPCM encoding.  Big endian versions of RIFF files, called RIFX,
              can also be read and written.  To write a RIFX file, use the  -B
              option with the output file options.

       .wve   Psion  8-bit  A-law.   Used  on  Psion  SIBO  PDAs (Series 3 and
              similar).

       .xa    Maxis XA files.  These are 16-bit  ADPCM  audio  files  used  by
              Maxis  games.   Writing  .xa  files  is currently not supported,
              although adding write support should not be very difficult.

       .xi (libsndfile)
              Fasttracker 2 Extended Instrument format.

SEE ALSO

       sox(1), soxeffect(7), libsox(3), octave(1), soxexam(7), wget(1)

       The SoX web page at http://sox.sourceforge.net

   References
       [1]    Wikipedia, M3U, http://en.wikipedia.org/wiki/M3U

       [2]    Wikipedia, PLS, http://en.wikipedia.org/wiki/PLS_(file_format)

AUTHORS

       Chris  Bagwell  (cbagwell@users.sourceforge.net).   Other  authors  and
       contributors  are  listed  in the AUTHORS file that is distributed with
       the source code.