SoX(7)                          Sound eXchange                          SoX(7)



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

DESCRIPTION
       This  manual  describes  SoX  supported  file  formats and audio device
       types; the SoX manual set starts with sox(1).

       Format types that can SoX can determine by  a  filename  extension  are
       listed  with  their  names  preceded  by  a dot.  Format types that are
       optionally built into SoX are marked `(optional)'.

       Format types that can be handled by an external library via an optional
       pseudo  file  type (currently sndfile 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.

       To see if SoX has support for an optional format or device,  enter  sox
       -h and look for its name under the list: `AUDIO FILE FORMATS' or `AUDIO
       DEVICE DRIVERS'.

   SOX FORMATS & DEVICE DRIVERS
       .raw (also with -t sndfile), .f32, .f64, .s8, .s16, .s24, .s32,
       .u8, .u16, .u24, .u32, .ul, .al, .lu, .la
              Raw (headerless) audio files.  For raw, the sample rate and  the
              data  encoding  must be given using command-line format options;
              for the other listed types, the sample  rate  defaults  to  8kHz
              (but may be overridden), and the data encoding is defined by the
              given suffix.  Thus f32 and f64 indicate files encoded as 32 and
              64-bit  (IEEE  single  and  double precision) floating point PCM
              respectively; s8, s16, s24, and s32  indicate  8,  16,  24,  and
              32-bit  signed  integer  PCM respectively; u8, u16, u24, and u32
              indicate 8, 16, 24, and  32-bit  unsigned  integer  PCM  respec‐
              tively;  ul  indicates  `μ-law'  (8-bit),  al  indicates `A-law'
              (8-bit), and lu and la are inverse bit order `μ-law' and inverse
              bit order `A-law' respectively.  For all raw formats, the number
              of channels defaults to 1 (but may be overridden).

              Headerless audio files on a SPARC computer are likely to  be  of
              format  ul;  on a Mac, they're likely to be u8 but with a sample
              rate of 11025 or 22050 Hz.

              See .ima and .vox for raw ADPCM formats, and .cdda  for  raw  CD
              digital audio.

       .f4, .f8, .s1, .s2, .s3, .s4,
       .u1, .u2, .u3, .u4, .sb, .sw, .sl, .ub, .uw
              Deprecated aliases for f32, f64, s8, s16, s24, s32,
              u8, u16, u24, u32, s8, s16, s32, u8, and u16 respectively.

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

       .aiff, .aif (also with -t sndfile)
              AIFF  files  as  used on old Apple Macs, Apple IIc/IIgs and SGI.
              SoX's AIFF support does not include 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.
              With Mac OS X, AIFF has been superseded by CAF.

       .aiffc, .aifc (also with -t sndfile)
              AIFF-C is a format based on AIFF that was created to allow  han‐
              dling compressed audio.  It can also handle little endian uncom‐
              pressed linear data that is often referred to as sowt  encoding.
              This  encoding  has  also  become the defacto format produced by
              modern Macs as well as iTunes on  any  platform.   AIFF-C  files
              produced by other applications typically have the file extension
              .aif and require looking at its header to detect the  true  for‐
              mat.  The sowt encoding is the only encoding that SoX can handle
              with this format.

              AIFF-C is 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.

       alsa (optional)
              Advanced Linux Sound Architecture device driver;  supports  both
              playing  and  recording audio.  ALSA is only used in Linux-based
              operating systems, though these often support OSS (see below) as
              well.  Examples:
                   sox infile -t alsa
                   sox infile -t alsa default
                   sox infile -t alsa plughw:0,0
                   sox -2 -t alsa hw:1 outfile
              See also play(1), rec(1), and sox(1) -d.

       .amb   Ambisonic  B-Format: a specialisation of .wav with between 3 and
              16 channels of audio for use with  an  Ambisonic  decoder.   See
              http://www.ambisonia.com/Members/mleese/file-format-for-b-format
              for details.  It is up to the user to get the channels  together
              in the right order and at the correct amplitude.

       .amr-nb (optional)
              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.

       .amr-wb (optional)
              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.

       ao (optional)
              Xiph.org's  Audio  Output  device driver; works only for playing
              audio.  It supports a wide range of devices and sound systems  -
              see  its  documentation  for the full range.  For the most part,
              SoX's use of libao cannot be configured directly; instead, libao
              configuration files must be used.

              The  filename  specified is used to determine which libao plugin
              to use.  Normally, you should specify `default' as the filename.
              If  that  doesn't give the desired behavior then you can specify
              the short name for a given plugin (such as pulse for pulse audio
              plugin).  Examples:
                   sox infile -t ao
                   sox infile -t ao default
                   sox infile -t ao pulse
              See also play(1) and sox(1) -d.

       .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.   To  write a DEC file, use the -L option with the output
              file options.

              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.

       .avr   Audio Visual Research format; used by  a  number  of  commercial
              packages on the Mac.

       .caf (optional)
              Apple's Core Audio File format.

       .cdda, .cdr
              `Red Book' Compact Disc Digital Audio (raw audio).  CDDA has two
              audio  channels  formatted  as  16-bit  signed   integers   (big
              endian)at  a  sample  rate  of 44.1 kHz.  The number of (stereo)
              samples in each CDDA track is always a multiple of 588.

       coreaudio (optional)
              Mac OSX CoreAudio  device  driver:  supports  both  playing  and
              recording  audio.   If a filename is not specific or if the name
              is "default" then the default audio  device  is  selected.   Any
              other  name will be used to select a specific device.  The valid
              names can be seen in the System Preferences->Sound menu and then
              under the Output and Input tabs.

              Examples:
                   sox infile -t coreaudio
                   sox infile -t coreaudio default
                   sox infile -t coreaudio "Internal Speakers"
              See also play(1), rec(1), and sox(1) -d.

       .cvsd, .cvs
              Continuously Variable Slope Delta modulation.  A headerless for‐
              mat 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.

       .cvu   Continuously Variable Slope Delta modulation (unfiltered).  This
              is an alternative handler for CVSD that is unfiltered but can be
              used with any bit-rate.  E.g.
                   sox infile outfile.cvu rate 28k
                   play -r 28k outfile.cvu sinc -3.4k

       .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, and one line that contains the  number
              of  channels.  Subsequent lines contain two or more numeric data
              intems: the time since the beginning of the first sample and the
              sample value for each channel.

              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.

              Example containing only 2 stereo samples of silence:

                  ; Sample Rate 8012
                  ; Channels 2
                              0   0    0
                  0.00012481278   0    0

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

       .fap (optional)
              See .paf.

       ffmpeg (optional)
              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).  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 (optional; also with -t sndfile)
              Xiph.org's  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 read native FLAC files (.flac) but not  Ogg  FLAC  files
              (.ogg).  [But see .ogg below for information relating to support
              for Ogg Vorbis files.]

              SoX can write native FLAC files according to a given or  default
              compression level.  8 is the default compression level and gives
              the best (but slowest)  compression;  0  gives  the  least  (but
              fastest)  compression.   The compression level is selected using
              the -C option [see sox(1)] with a whole number from 0 to 8.

       .fssd  An alias for the .u8 format.

       .gsrt  Grandstream ring-tone files.  Whilst this file format  can  con‐
              tain  A-Law,  μ-law,  GSM,  G.722,  G.723, G.726, G.728, or iLBC
              encoded audio, SoX supports reading and writing only  A-Law  and
              μ-law.  E.g.
                 sox music.wav -t gsrt ring.bin
                 play ring.bin

       .gsm (optional; also with -t sndfile)
              GSM  06.10  Lossy  Speech  Compression.  A lossy format for com‐
              pressing 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.

       .hcom  Macintosh  HCOM  files.   These  are Mac FSSD files with Huffman
              compression.

       .htk   Single channel 16-bit PCM format used  by  HTK,  a  toolkit  for
              building Hidden Markov Model speech processing tools.

       .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 implemen‐
              tation is headerless.

       .mat, .mat4, .mat5 (optional)
              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.  SoX can
              read, but not write this file format.  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 (optional read, optional write)
              MP3 compressed audio; MP3 (MPEG  Layer  3)  is  a  part  of  the
              patent-encumbered  MPEG  standards  for audio and video compres‐
              sion.  It is a lossy compression format that achieves good  com‐
              pression rates with little quality loss.

              Because MP3 is patented, SoX cannot be distributed with MP3 sup‐
              port without incurring the  patent  holder's  fees.   Users  who
              require  SoX  with  MP3 support must currently compile and build
              SoX with the MP3 libraries (LAME & MAD) from source code, or, in
              some cases, obtain pre-built dynamically loadable libraries.

              When  reading  MP3  files,  up to 28 bits of precision is stored
              although only 16 bits is reported to user.   This  is  to  allow
              default  behavior  of  writing  16 bit output files.  A user can
              specify a higher precision for the output file to prevent  loss‐
              ing  this extra information.  MP3 output files will use up to 24
              bits of precision while encoding.

              MP3 compression parameters can be selected using SoX's -C option
              as follows (note that the current syntax is subject to change):

              The  primary  parameter  to the LAME encoder is the bit rate. If
              the value of the -C value is a positive integer, it's  taken  as
              the bitrate in kbps (e.g. if you specify 128, it uses 128 kbps).

              The  second  most  important  parameter  is  probably  "quality"
              (really performance), which allows balancing encoding speed  vs.
              quality.  In LAME, 0 specifies highest quality but is very slow,
              while 9 selects poor quality, but is fast. (5 is the default and
              2 is recommended as a good trade-off for high quality encodes.)

              Because  the -C value is a float, the fractional part is used to
              select quality. 128.2 selects 128 kbps encoding with  a  quality
              of  2.  There  is one problem with this approach. We need 128 to
              specify 128 kbps encoding with default quality, so 0  means  use
              default.  Instead  of  0 you have to use .01 (or .99) to specify
              the highest quality (128.01 or 128.99).

              LAME uses bitrate to specify  a  constant  bitrate,  but  higher
              quality can be achieved using Variable Bit Rate (VBR). VBR qual‐
              ity (really size) is selected using a number from 0 to 9. Use  a
              value  of  0  for  high quality, larger files, and 9 for smaller
              files of lower quality. 4 is the default.

              In order to squeeze the selection of VBR into the the  -C  value
              float  we  use negative numbers to select VRR. -4.2 would select
              default VBR encoding (size) with high quality (speed). One  spe‐
              cial  case is 0, which is a valid VBR encoding parameter but not
              a valid bitrate.  Compression value of 0 is always treated as  a
              high  quality  vbr, as a result both -0.2 and 0.2 are treated as
              highest quality VBR (size) and high quality (speed).

              See also Ogg Vorbis for a similar format.

       .mp4, .m4a (optional)
              MP4 compressed audio.  MP3 (MPEG 4) is part of  the  MPEG  stan‐
              dards  for audio and video compression.  See mp3 for more infor‐
              mation.

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

       .ogg, .vorbis (optional)
              Xiph.org's Ogg Vorbis compressed  audio;  an  open,  patent-free
              CODEC  designed  for  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.

              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.  Decod‐
              ing is somewhat CPU intensive and encoding is  very  CPU  inten‐
              sive.

              See also .mp3 for a similar format.

       oss (optional)
              Open  Sound System /dev/dsp device driver; supports both playing
              and recording audio.  OSS  support  is  available  in  Unix-like
              operating  systems,  sometimes  together  with alternative sound
              systems (such as ALSA).  Examples:
                   sox infile -t oss
                   sox infile -t oss /dev/dsp
                   sox -2 -t oss /dev/dsp outfile
              See also play(1), rec(1), and sox(1) -d.

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

       .pls   A playlist format; contains a list  of  audio  files.   SoX  can
              read,  but  not  write this file format.  See [2] for details of
              this format.

              Note: SoX support for 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 simi‐
              lar) 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.

       pulseaudio (optional)
              PulseAudio driver; supports both playing and recording of audio.
              PulseAudio  is  a  cross  platform networked sound server.  If a
              file name is specified with this driver, it is  ignored.   Exam‐
              ples:
                   sox infile -t pulseaudio
                   sox infile -t pulseaudio default
              See also play(1), rec(1), and sox(1) -d.

       .pvf (optional)
              Portable Voice Format.

       .sd2 (optional)
              Sound Designer 2 format.

       .sds (optional)
              MIDI Sample Dump Standard.

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

       .sln   Asterisk PBX `signed linear' 8khz, 16-bit signed  integer,  lit‐
              tle-endian raw format.

       .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 con‐
              tain 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 sam‐
              ple rates are supported by the package,  although  not  all  are
              supported by the samplers themselves.  Currently loop points are
              ignored.

       .snd   See .au, .sndr and .sndt.

       sndfile (optional)
              This is a pseudo-type that forces libsndfile  to  be  used.  For
              writing  files, the actual file type is then taken from the out‐
              put file name; for reading them, it is deduced from the file.

       sndio (optional)
              OpenBSD audio device driver; supports both playing and recording
              audio.
                   sox infile -t sndio
              See also play(1), rec(1), and sox(1) -d.

       .sndr  Sounder  files.   An  MS-DOS/Windows format from the early '90s.
              Sounder files usually have the extension `.SND'.

       .sndt  SoundTool files.  An MS-DOS/Windows format from the early  '90s.
              SoundTool files usually have the extension `.SND'.

       .sou   An alias for the .u8 raw format.

       .sox   SoX's  native  uncompressed PCM format, intended for storing (or
              piping) audio at intermediate processing  points  (i.e.  between
              SoX  invocations).   It has much in common with the popular WAV,
              AIFF, and AU uncompressed PCM formats,  but  has  the  following
              specific  characteristics:  the PCM samples are always stored as
              32 bit signed integers, the samples are stored (by  default)  as
              `native  endian',  and  the  number  of  samples  in the file is
              recorded as a 64-bit integer.  Comments are also supported.

              See `Special Filenames' in sox(1) for examples of using the .sox
              format with `pipes'.

       sunau (optional)
              Sun  /dev/audio device driver; supports both playing and record‐
              ing audio.  For example:
                   sox infile -t sunau /dev/audio
              or
                   sox infile -t sunau -U -c 1 /dev/audio
              for older sun equipment.

              See also play(1), rec(1), and sox(1) -d.

       .txw   Yamaha TX-16W sampler.  A file format  from  a  Yamaha  sampling
              keyboard which wrote IBM-PC format 3.5" floppies.  Handles read‐
              ing 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  sam‐
              ple 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.   SoX  supports  reading (but not writing) VOC files with
              multiple  blocks,  and  files  containing  μ-law,   A-law,   and
              2/3/4-bit ADPCM 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  pre‐
              cision 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  off‐
              set  can be removed by passing the decoded audio through a high-
              pass filter, e.g.:
                   sox input.vox output.wav highpass 10

       .w64 (optional)
              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 can read and write linear PCM, floating point, μ-law, A-law,
              MS ADPCM, and IMA (or DVI) ADPCM encoded samples.  WAV files can
              also contain audio encoded in many  other  ways  (not  currently
              supported  with  SoX)  e.g.  MP3;  in some cases such a file can
              still be read by SoX by overriding the file type, e.g.
                 play -t mp3 mp3-encoded.wav
              Big endian versions of RIFF files, called RIFX,  are  also  sup‐
              ported.  To write a RIFX file, use the -B option with the output
              file options.

       waveaudio (optional)
              MS-Windows native audio device driver.  Examples:
                   sox infile -t waveaudio
                   sox infile -t waveaudio default
                   sox infile -t waveaudio 1
                   sox infile -t waveaudio "High Definition Audio Device ("
              If the device name is omitted, -1, or default, then you get  the
              `Microsoft Wave Mapper' device.  Wave Mapper means `use the sys‐
              tem default audio devices'.   You  can  control  what  `default'
              means via the OS Control Panel.

              If  the  device  name  given  is some other number, you get that
              audio device by index; so recording with device name 0 would get
              the first input device (perhaps the microphone), 1 would get the
              second (perhaps line in), etc.  Playback using 0  will  get  the
              first output device (usually the only audio device).

              If  the  device name given is something other than a number, SoX
              tries to match it (maximum 31 characters) against the  names  of
              the available devices.

              See also play(1), rec(1), and sox(1) -d.

       .wavpcm
              A non-standard, but widely used, variant of .wav.  Some applica‐
              tions cannot read a standard WAV  file  header  for  PCM-encoded
              data with sample-size greater than 16-bits or with more than two
              channels, but can read a non-standard WAV header.  It is  likely
              that such applications will eventually be updated to support the
              standard header, but in the mean time, this SoX  format  can  be
              used  to  create  files with the non-standard header that should
              work with these applications.  (Note that SoX will automatically
              detect and read WAV files with the non-standard header.)

              The  most common use of this file-type is likely to be along the
              following lines:
                   sox infile.any -t wavpcm -s outfile.wav

       .wv (optional)
              WavPack lossless audio compression.  Note that, when  converting
              .wav  to this format and back again, the RIFF header is not nec‐
              essarily preserved losslessly (though the audio is).

       .wve (also with -t sndfile)
              Psion 8-bit A-law.  Used on Psion SIBO PDAs (Series 3 and  simi‐
              lar).  This format is deprecated in SoX, but will continue to be
              used in libsndfile.

       .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 (optional)
              Fasttracker 2 Extended Instrument format.

SEE ALSO
       sox(1), soxi(1), libsox(3), octave(1), wget(1)

       The SoX web page at http://sox.sourceforge.net
       SoX scripting examples at http://sox.sourceforge.net/Docs/Scripts

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

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

LICENSE
       Copyright 1998-2013 Chris Bagwell and SoX Contributors.
       Copyright 1991 Lance Norskog and Sundry Contributors.

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



soxformat                      February 1, 2013                         SoX(7)
