1The current release handles the following audio file formats:
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3(:cellnr:)
4* Raw files in various binary formats
5* Raw textual data
6* Amiga 8svx files
7* Apple/SGI AIFF files
8* SUN .au files
9** PCM, u-law, A-law
10** G7xx ADPCM files (read only)
11** mutant DEC .au files
12** NeXT .snd files
13* AVR files
14* CDDA (Compact Disc Digital Audio format)
15* CVS and VMS files (continuous variable slope)
16* Grandstream ring-tone files
17* GSM files
18* HTK files
19* LPC-10 files
20* Macintosh HCOM files
21* Amiga MAUD files
22* AMR-WB & AMR-NB (with optional libamrwb & libamrnb libraries)
23* MP2/MP3 (with optional libmad, libtwolame and libmp3lame libraries)
24* Opus files (read only; with optional Opus libraries)
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26* Ogg Vorbis files (with optional Ogg Vorbis libraries)
27* FLAC files (with optional libFLAC)
28* IRCAM SoundFile files
29* NIST SPHERE files
30* Turtle beach SampleVision files
31* Sounder & Soundtool (DOS) files
32* Yamaha TX-16W sampler files
33* SoundBlaster .VOC files
34* Dialogic/OKI ADPCM files (.VOX)
35* Microsoft .WAV files
36** PCM, floating point
37** u-law, A-law, MS ADPCM, IMA (DMI) ADPCM
38** GSM
39** RIFX (big endian)
40* WavPack files (with optional libwavpack library)
41* Psion (palmtop) A-law WVE files and Record voice notes
42* Maxis XA Audio files
43** EA ADPCM (read support only, for now)
44* Pseudo formats that allow direct playing/recording from most audio devices
45* The "null" pseudo-file that reads and writes from/to nowhere
46(:tableend:)
47
48The audio effects/tools included in this release are as follows:
49
50* Tone/filter effects
51** allpass: RBJ all-pass biquad IIR filter
52** bandpass: RBJ band-pass biquad IIR filter
53** bandreject: RBJ band-reject biquad IIR filter
54** band: SPKit resonator band-pass IIR filter
55** bass: Tone control: RBJ shelving biquad IIR filter
56** equalizer: RBJ peaking equalisation biquad IIR filter
57** firfit+: FFT convolution FIR filter using given freq. response (W.I.P.)
58** highpass: High-pass filter: Single pole or RBJ biquad IIR
59** hilbert: Hilbert transform filter (90 degrees phase shift)
60** lowpass: Low-pass filter: single pole or RBJ biquad IIR
61** sinc: Sinc-windowed low/high-pass/band-pass/reject FIR
62** treble: Tone control: RBJ shelving biquad IIR filter
63
64* Production effects
65** chorus: Make a single instrument sound like many
66** delay: Delay one or more channels
67** echo: Add an echo
68** echos: Add a sequence of echos
69** flanger: Stereo flanger
70** overdrive: Non-linear distortion
71** phaser: Phase shifter
72** repeat: Loop the audio a number of times
73** reverb: Add reverberation
74** reverse: Reverse the audio (to search for Satanic messages ;-)
75** tremolo: Sinusoidal volume modulation
76
77* Volume/level effects
78** compand: Signal level compression/expansion/limiting
79** contrast: Phase contrast volume enhancement
80** dcshift: Apply or remove DC offset
81** fade: Apply a fade-in and/or fade-out to the audio
82** gain: Apply gain or attenuation; normalise/equalise/balance/headroom
83** loudness: Gain control with ISO 226 loudness compensation
84** mcompand: Multi-band compression/expansion/limiting
85** norm: Normalise to 0dB (or other)
86** vol: Adjust audio volume
87
88* Editing effects
89** pad: Pad (usually) the ends of the audio with silence
90** silence: Remove portions of silence from the audio
91** splice: Perform the equivalent of a cross-faded tape splice
92** trim: Cuts portions out of the audio
93** vad: Voice activity detector
94
95* Mixing effects
96** channels: Auto mix or duplicate to change number of channels
97** divide+: Divide sample values by those in the 1st channel (W.I.P.)
98** remix: Produce arbitrarily mixed output channels
99** swap: Swap pairs of channels
100
101* Pitch/tempo effects
102** bend: Bend pitch at given times without changing tempo
103** pitch: Adjust pitch (= key) without changing tempo
104** speed: Adjust pitch & tempo together
105** stretch: Adjust tempo without changing pitch (simple alg.)
106** tempo: Adjust tempo without changing pitch (WSOLA alg.)
107
108* Mastering effects
109** dither: Add dither noise to increase quantisation SNR
110** rate: Change audio sampling rate
111
112* Specialised filters/mixers
113** deemph: ISO 908 CD de-emphasis (shelving) IIR filter
114** earwax: Process CD audio to best effect for headphone use
115** noisered: Filter out noise from the audio
116** oops: Out Of Phase Stereo (or `Karaoke') effect
117** riaa: RIAA vinyl playback equalisation
118
119* Analysis `effects'
120** noiseprof: Produce a DFT profile of the audio (use with noisered)
121** spectrogram: graph signal level vs. frequency & time (needs `libpng')
122** stat: Enumerate audio peak & RMS levels, approx. freq., etc.
123** stats: Multichannel aware `stat'
124
125* Miscellaneous effects
126** ladspa: Apply LADSPA plug-in effects e.g. CMT (Computer Music Toolkit)
127** synth: Synthesise/modulate audio tones or noise signals
128** newfile: Create a new output file when an effects chain ends.
129** restart: Restart 1st effects chain when multiple chains exist.
130
131* Low-level signal processing effects
132** biquad: 2nd-order IIR filter using externally provided coefficients
133** downsample: Reduce sample rate by discarding samples
134** fir: FFT convolution FIR filter using externally provided coefficients
135** upsample: Increase sample rate by zero stuffing
136
137  + Experimental or incomplete effect; may change in future.
138
139Multiple audio files can be combined (and then further processed with
140effects) using any one of the following combiner methods:
141
142* concatenate
143* mix
144* merge: E.g. two mono files to one stereo file
145* sequence: For playing multiple audio files/streams
146