			   SoX: Sound eXchange
			   ===================

SoX (Sound eXchange) is another Swiss Army knife of sound processing tools:
it can convert sound files between many different file formats & audio devices,
and can apply many sound effects & transformations, as well as doing basic
analysis and providing input to more capable analysis and plotting tools.

SoX is licensed under the GNU GPL and GNU LGPL.  To be precise, the 'sox_ng'
and 'soxi_ng' programs are distributed under the GPL, while the library
'libsox_ng' (in which most of SoX's functionality resides) is dual-licensed.
Note that some optional components of libsox_ng are GPL only: if you use these,
you must use libsox_ng under the GPL.  See INSTALL for the list of optional
components and their licences.

If this distribution is of source code (as opposed to pre-built binaries),
then you will need to compile and install SoX as described in the 'INSTALL'
file.

Changes between this release and previous releases of SoX can be found in
the 'ChangeLog' file; a summary of the file formats and effects supported in
this release can be found below.  Detailed documentation for using SoX can
be found in the distributed 'man' pages:
  o  sox_ng(1)
  o  soxi_ng(1)
  o  soxformat_ng(7)
  o  libsox_ng(3)

or in plain text or PDF files for those systems without man.

The majority of SoX features and fixes are contributed by SoX users - thank
you very much for making SoX a success!  There are several new features
wanted for SoX, listed on the feature request tracker at the SoX
project home-page:

		    https://codeberg.org/sox_ng/sox_ng/issues

users are encouraged to implement them!

Please submit bug reports, new feature requests, and patches to the relevant
tracker at the above address, or by email:

		   mailto:sox-ng@groups.io

The current release handles the following audio file formats:

  o  Raw files in various binary formats
  o  Raw textual data
  o  Amiga 8svx files
  o  AMR-WB & AMR-NB (with optional libamrwb & libamrnb libraries)
  o  Apple/SGI AIFF files
    o  PCM, sowt, A-law, u-law
  o  SUN .au files
    o  PCM, u-law, A-law
    o  G7xx ADPCM files (read only)
    o  mutant DEC .au files
    o  NeXT .snd files
  o  AVR files
  o  CDDA (Compact Disc Digital Audio format)
  o  CVS and VMS files (continuous variable slope)
  o  DSD, DSF, DSDIFF and WSD files
  o  Grandstream ring-tone files
  o  GSM files
  o  Macintosh HCOM files
  o  HTK files
  o  LPC-10 files
  o  Amiga MAUD files
  o  MP2/MP3 (with optional libmad, libtwolame and libmp3lame libraries)
  o  Opus files (read only; with optional Opus libraries)
  o  Ogg Vorbis files (with optional Ogg Vorbis libraries)
  o  FLAC files (with optional libFLAC)
  o  IRCAM SoundFile files
  o  NIST SPHERE files
  o  CSL NSP audio/bioelectric files
  o  SDS format
  o  SoundBlaster .VOC files
  o  Sounder & Soundtool (DOS) files
  o  Turtle beach SampleVision files
  o  Dialogic/OKI ADPCM .VOX files
  o  Microsoft .WAV files
    o  PCM, floating point
    o  u-law, A-law, MS ADPCM, IMA (DMI) ADPCM
    o  GSM
    o  RIFX (big endian)
  o  WavPack files (with optional libwavpack library)
  o  Yamaha TX-16W sampler files
  o  Akai MSP2K sampler files
  o  Psion (palmtop) A-law WVE files and Record voice notes
  o  Maxis XA Audio files
    o  EA ADPCM (read support only, for now)
  o  Pseudo formats that allow direct playing/recording from audio devices
  o  The "null" pseudo-file that reads and writes from/to nowhere

and if the `ffmpeg' program is installed it automatically reads:

  o  3GP/3GPP files
  o  Audible Audiobook files
  o  AAC Advanced Audio Coding files
  o  AC3 Dolby Digital files
  o  ACT files (G729A speech compression)
  o  CRI ADX files
  o  Advanced / Active Streaming Format ASF files
  o  APTX Audio Processing Technology for Bluetooth files
  o  Argonaut Games ASF files
  o  AST Audio stream files
  o  AVI Audio Video Interleaved files
  o  DFPWM1a files
  o  DTS Digital Theatre System files
  o  Electronic Arts Multimedia files
  o  Enhanced AC-3 Audio files
  o  GXF General eXchange Format files
  o  Lego Mindstorms RSO files
  o  LOAS AudioSyncStream files
  o  Loki SDL MJPEG files
  o  M4A MPEG-4 Audio files
  o  M4V/MP4 MPEG-4 Video files
  o  Macromedia Flash Video files
  o  Meridian Lossless Packing
  o  Monkey's Audio (APE) files
  o  MPEG-1 Program Stream files
  o  MPEG-2 Transport Stream files
  o  NUT audio files
  o  Ogg Speex files
  o  Ogg FLAC files
  o  RealAudio files
  o  RealMedia files
  o  SBC files
  o  Simon & Schuster Interactive KVAG files
  o  Sony PS2 VAG files
  o  S/PDIF (IEC 61937) files
  o  True Audio TTA files
  o  Unisoft Rayman 2 APM files
  o  Westwood Studios Audio files
  o  Windows Media Audio files
  o  Windows Television files

The audio effects/tools included in this release are as follows:

  o  Tone/filter effects
    o  allpass: RBJ all-pass biquad IIR filter
    o  bandpass: RBJ band-pass biquad IIR filter
    o  bandreject: RBJ band-reject biquad IIR filter
    o  band: SPKit resonator band-pass IIR filter
    o  bass: Tone control: RBJ shelving biquad IIR filter
    o  dolbyb: Noise reduction encoding and decoding
    o  equalizer: RBJ peaking equalisation biquad IIR filter
    o  firfit: FFT convolution FIR filter using given freq. response (W.I.P.)
    o  highpass: High-pass filter: Single pole or RBJ biquad IIR
    o  hilbert: Hilbert transform filter (90 degrees phase shift)
    o  lowpass: Low-pass filter: single pole or RBJ biquad IIR
    o  sinc: Sinc-windowed low/high-pass/band-pass/reject FIR
    o  speexdsp: Automatic gain control, denoise and dereverb
    o  treble: Tone control: RBJ shelving biquad IIR filter

  o  Production effects
    o  chorus: Make a single instrument sound like many
    o  delay: Delay one or more channels
    o  echo: Add an echo
    o  echos: Add a sequence of echos
    o  flanger: Stereo flanger
    o  overdrive: Non-linear distortion
    o  phaser: Phase shifter
    o  repeat: Loop the audio a number of times
    o  reverb: Add reverberation
    o  reverse: Reverse the audio (to search for Satanic messages ;-)
    o  saturation: Soft clipping effects from subtle warmth to crunchy fuzz
    o  tremolo: Sinusoidal volume modulation

  o  Volume/level effects
    o  compand: Signal level compression/expansion/limiting
    o  contrast: Phase contrast volume enhancement
    o  dcshift: Apply or remove DC offset
    o  fade: Apply a fade-in and/or fade-out to the audio
    o  gain: Apply gain or attenuation; normalise/equalise/balance/headroom
    o  loudness: Gain control with ISO 226 loudness compensation
    o  mcompand: Multi-band compression/expansion/limiting
    o  norm: Normalise to 0dB (or other)
    o  softvol: A software volume control that avoids clipping and maybe rises
    o  vol: Adjust audio volume

  o  Editing effects
    o  pad: Pad (usually) the ends of the audio with silence
    o  silence: Remove portions of silence from the audio
    o  splice: Perform the equivalent of a cross-faded tape splice
    o  trim: Cuts portions out of the audio
    o  vad: Voice activity detector

  o  Mixing effects
    o  channels: Auto mix or duplicate to change number of channels
    o  remix: Produce arbitrarily mixed output channels
    o  swap: Swap pairs of channels

  o  Pitch/tempo effects
    o  bend: Bend pitch at given times without changing tempo
    o  pitch: Adjust pitch (= key) without changing tempo
    o  speed: Adjust pitch & tempo together
    o  stretch: Adjust tempo without changing pitch (simple alg.)
    o  tempo: Adjust tempo without changing pitch (WSOLA alg.)

  o  Mastering effects
    o  dither: Add dither noise to increase quantisation SNR
    o  rate: Change audio sampling rate

  o  Specialised filters/mixers
    o  centercut: A "vocal cut" filter giving left, right and center separately
    o  deemph: ISO 908 CD de-emphasis (shelving) IIR filter
    o  dop: DSD over PCM, packing 1-bit samples into 24-bit ones
    o  earwax: Process CD audio to best effect for headphone use
    o  noisered: Filter out noise from the audio
    o  oops: Out Of Phase Stereo (or `Karaoke') effect
    o  riaa: RIAA vinyl playback equalisation
    o  sdm: Sigma-Delta Modulation for Direct Stream Digital format

  o  Analysis `effects'
    o  noiseprof: Produce a DFT profile of the audio (use with noisered)
    o  spectrogram: graph signal level vs. frequency & time (needs `libpng')
    o  stat: Enumerate audio peak & RMS levels, approx. freq., etc.
    o  stats: Multichannel aware `stat'

  o  Miscellaneous effects
    o  ladspa: Apply LADSPA plug-in effects e.g. CMT (Computer Music Toolkit)
    o  synth: Synthesise/modulate audio tones or noise signals

  o  Pseudo effects
    o  newfile: Create a new output file when an effects chain ends.
    o  restart: Restart 1st effects chain when multiple chains exist.

  o  Low-level signal processing effects
    o  biquad: 2nd-order IIR filter using externally provided coefficients
    o  downsample: Reduce sample rate by discarding samples
    o  fir: FFT convolution FIR filter using externally provided coefficients
    o  upsample: Increase sample rate by zero stuffing

Multiple audio files can be combined (and then further processed with
effects) using any one of the following combiner methods:

  o  concatenate
  o  merge: E.g. two mono files to one stereo file
  o  mix
  o  mix-power: Mix to equal power
  o  multiply
  o  sequence: For playing multiple audio files/streams
