The current release handles the following audio file formats:
	•	Raw files in various binary formats
	•	Raw textual data
	•	Amiga 8svx files
	•	Apple/SGI AIFF files
	•	SUN .au files
	◦	PCM, u-law, A-law
	◦	G7xx ADPCM files (read only)
	◦	mutant DEC .au files
	◦	NeXT .snd files
	•	AVR files
	•	CDDA (Compact Disc Digital Audio format)
	•	CVS and VMS files (continuous variable slope)
	•	Grandstream ring-tone files
	•	GSM files
	•	HTK files
	•	LPC-10 files
	•	Macintosh HCOM files
	•	Amiga MAUD files
	•	AMR-WB & AMR-NB (with optional libamrwb & libamrnb libraries)
	•	MP3 (with optional libmad and libmp3lame libraries)
	•	MP4, AAC, AC3, WAVPACK, AMR-NB files (with optional ffmpeg library)
	•	AVI, WMV, Ogg Theora, MPEG video files (with optional ffmpeg library)		•	Ogg Vorbis files (with optional Ogg Vorbis libraries)
	•	FLAC files (with optional libFLAC)
	•	IRCAM SoundFile files
	•	NIST SPHERE files
	•	Turtle beach SampleVision files
	•	Sounder & Soundtool (DOS) files
	•	Yamaha TX-16W sampler files
	•	SoundBlaster .VOC files
	•	Dialogic/OKI ADPCM files (.VOX)
	•	Microsoft .WAV files
	◦	PCM, u-law, A-law
	◦	MS ADPCM, IMA ADPCM
	◦	GSM
	◦	RIFX (big endian)
	•	WavPack files (with optional libwavpack library)
	•	Psion (palmtop) A-law WVE files and Record voice notes
	•	Maxis XA Audio files
	◦	EA ADPCM (read support only, for now)
	•	Pseudo formats that allow direct playing/recording from most audio devices
	•	The "null" pseudo-file that reads and writes from/to nowhere	
The audio effects/tools included in this release are as follows:

	•	Tone/filter effects
	◦	allpass: RBJ all-pass biquad IIR filter
	◦	bandpass: RBJ band-pass biquad IIR filter
	◦	bandreject: RBJ band-reject biquad IIR filter
	◦	band: SPKit resonator band-pass IIR filter
	◦	bass: Tone control: RBJ shelving biquad IIR filter
	◦	biquad: 2nd-order IIR filter using externally provided coefficients
	◦	equalizer: RBJ peaking equalisation biquad IIR filter
	◦	fir: FFT convolution FIR filter using externally provided coefficients
	◦	firfit+: FFT convolution FIR filter using given freq. response (W.I.P.)
	◦	highpass: High-pass filter: Single pole or RBJ biquad IIR
	◦	lowpass: Low-pass filter: single pole or RBJ biquad IIR
	◦	sinc: Sinc-windowed low/high-pass/band-pass/reject FIR
	◦	treble: Tone control: RBJ shelving biquad IIR filter
	•	
	•	Production effects
	◦	chorus: Make a single instrument sound like many
	◦	delay: Delay one or more channels
	◦	echo: Add an echo
	◦	echos: Add a sequence of echos
	◦	flanger: Stereo flanger
	◦	overdrive: Non-linear distortion
	◦	phaser: Phase shifter
	◦	repeat: Loop the audio a number of times
	◦	reverb: Add reverberation
	◦	reverse: Reverse the audio (to search for Satanic messages ;-)
	◦	tremolo: Sinusoidal volume modulation
	•	
	•	Volume/level effects
	◦	compand: Signal level compression/expansion/limiting
	◦	contrast: Phase contrast volume enhancement
	◦	dcshift: Apply or remove DC offset
	◦	fade: Apply a fade-in and/or fade-out to the audio
	◦	gain: Apply gain or attenuation; normalise/equalise/balance/headroom
	◦	loudness: Gain control with ISO 226 loudness compensation
	◦	mcompand: Multi-band compression/expansion/limiting
	◦	norm: Normalise to 0dB (or other)
	◦	vol: Adjust audio volume
	•	
	•	Editing effects
	◦	crop+: Like `trim', but can crop end without specifying length (W.I.P.)
	◦	pad: Pad (usually) the ends of the audio with silence
	◦	silence: Remove portions of silence from the audio
	◦	splice: Perform the equivalent of a cross-faded tape splice
	◦	trim: Trim the ends of the audio
	◦	vad: Voice activity detector
	•	
	•	Mixing effects
	◦	channels: Auto mix or duplicate to change number of channels
	◦	divide+: Divide sample values by those in the 1st channel (W.I.P.)
	◦	mixer: Mix up to 4 channels in certain ways
	◦	remix: Produce arbitrarily mixed output channels
	◦	swap: Swap stereo channels
	•	
	•	Pitch/tempo effects
	◦	bend: Bend pitch at given times without changing tempo
	◦	pitch: Adjust pitch (= key) without changing tempo
	◦	speed: Adjust pitch & tempo together
	◦	stretch: Adjust tempo without changing pitch (simple alg.)
	◦	tempo: Adjust tempo without changing pitch (WSOLA alg.)
	•	
	•	Mastering effects
	◦	dither: Add dither noise to increase quantisation SNR
	◦	rate: Change audio sampling rate
	•	
	•	Specialised filters/mixers
	◦	deemph: ISO 908 CD de-emphasis (shelving) IIR filter
	◦	earwax: Process CD audio to best effect for headphone use
	◦	noisered: Filter out noise from the audio
	◦	oops: Out Of Phase Stereo (or `Karaoke') effect
	◦	riaa: RIAA vinyl playback equalisation
	•	
	•	Analysis `effects'
	◦	noiseprof: Produce a DFT profile of the audio (use with noisered)
	◦	spectrogram: graph signal level vs. frequency & time (needs `libpng')
	◦	stat: Enumerate audio peak & RMS levels, approx. freq., etc.
	◦	stats: Multichannel aware `stat'
	•	
	•	Miscellaneous effects
	◦	ladspa: Apply LADSPA plug-in effects e.g. CMT (Computer Music Toolkit)
	◦	synth: Synthesise/modulate audio tones or noise signals
	◦	newfile: Create a new output file when an effects chain ends.
	◦	restart: Restart 1st effects chain when multiple chains exist.
	•	 + Experimental or incomplete effect; may change in future.
Multiple audio files can be combined (and then further processed with effects) using any one of the following combiner methods:

	•	concatenate
	•	mix
	•	merge: E.g. two mono files to one stereo file
	•	sequence: For playing multiple audio files/streams

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