Here is a list of all documented files with brief descriptions:

[detail level 12]

include
biquad.h	Biquad (second-order IIR) filter interface
fileio.h	Audio file I/O and feature vector writing
liveio.h	Live audio recording and playback via PortAudio
minidsp.h	A mini library of DSP (Digital Signal Processing) routines
src
biquad.c	Biquad (second-order IIR) filter implementation
fileio.c	Audio file I/O and feature vector writing
liveio.c	Live audio recording and playback implementation
minidsp_core.c	Stateless signal math: dot product, energy, power, entropy, scaling, AGC, time-domain pitch estimation, simple effects, and window function generation
minidsp_dtmf.c	DTMF tone detection and generation
minidsp_error.c	Configurable error handler for precondition violations
minidsp_fir.c	FIR filtering and convolution: direct time-domain methods and FFT overlap-add fast convolution
minidsp_gcc.c	GCC-PHAT delay estimation: cross-correlation, delay search, and multi-signal delay estimation
minidsp_generators.c	Signal generators: sine, white noise, impulse, chirps, square, sawtooth waves, and Shepard tone
minidsp_internal.h	Internal header for cross-file dependencies within the minidsp module
minidsp_resample.c	Polyphase sinc resampler for offline sample rate conversion
minidsp_spectext.c	Spectrogram text art: synthesise audio that displays readable text when viewed as a spectrogram
minidsp_spectrum.c	FFT-based spectrum analysis: magnitude spectrum, PSD, phase spectrum, STFT, mel filterbanks, MFCCs, FFT-based F0 estimation, and MD_shutdown()
minidsp_steg.c	Audio steganography: hide secret messages inside audio signals
minidsp_vad.c	Voice Activity Detection (VAD) with adaptive feature normalization