MDFEchoCancellation.h File Reference

#include <algorithm>
#include <cmath>
#include <cstdint>
#include <cstdlib>
#include <cstring>
#include <type_traits>
#include "MDFEchoCancellationConfig.h"
#include "PseudoFloat.h"
#include "AudioTools/FFT/AudioFFT.h"
#include "AudioTools/CoreAudio/AudioBasic/Collections/Allocator.h"
#include "AudioTools/CoreAudio/AudioTypes.h"

Go to the source code of this file.

Classes
struct	EchoState< T, SampleType >
	Internal echo canceller state structure. More...
struct	fft_state
	FFT state management structure. More...
class	MDFEchoCancellation< T, SampleType >
	Acoustic echo canceller using MDF algorithm. More...
struct	MDFFixedPoint
	Selects PseudoFloat (see PseudoFloat.h) as MDFEchoCancellation's internal numeric representation, so the algorithm runs on integer mantissa/exponent arithmetic instead of native float instructions – useful on microcontrollers without an FPU. PseudoFloat's arithmetic is verified against native float directly (see the PseudoFloat tests in tests-cmake/stt/stt_test.cpp), and MDFEchoCancellation<int16_t, MDFFixedPoint> is smoke-tested to run without crashing/NaN and to converge similarly to MDFFloat on the same synthetic signal – but it has not received the same depth of numerical scrutiny as MDFFloat, so treat it as less battle-tested. Despite the name, this is not a classic narrow Q15 fixed-point format (that would over/underflow across this algorithm's actual value range – see PseudoFloat's class doc for why). More...
struct	MDFFloat
	Selects float as MDFEchoCancellation's internal numeric representation for sample/spectrum arrays (word16_t/word32_t) and wide-dynamic-range control state (float_t). This is the default, and the one that has been verified to converge (see test_mdf_converges in tests-cmake/stt/stt_test.cpp) – prefer it unless you specifically need to avoid hardware floating-point instructions (e.g. no FPU). More...

Namespaces
namespace	audio_tools
	Generic Implementation of sound input and output for desktop environments using portaudio.

Macros
#define	ECHO_GET_FRAME_SIZE   3
#define	ECHO_GET_IMPULSE_RESPONSE   29
#define	ECHO_GET_IMPULSE_RESPONSE_SIZE   27
#define	ECHO_GET_SAMPLING_RATE   25
#define	ECHO_SET_SAMPLING_RATE   24

Typedefs
using	echo_int16_t = int16_t
using	echo_int32_t = int32_t
using	echo_uint16_t = uint16_t
using	echo_uint32_t = uint32_t

Functions
template<typename T >
void	echo_fft (void *table, T *in, T *out)
	Perform forward FFT.
void	echo_fft_destroy (void *table)
	Destroy FFT state and release resources.
void *	echo_fft_init (int size, FFTDriver *driver)
	Initialize FFT state.
template<typename T >
void	echo_ifft (void *table, T *in, T *out)
	Perform inverse FFT.

Macro Definition Documentation

ECHO_GET_FRAME_SIZE

#define ECHO_GET_FRAME_SIZE   3

ECHO_GET_IMPULSE_RESPONSE

#define ECHO_GET_IMPULSE_RESPONSE   29

ECHO_GET_IMPULSE_RESPONSE_SIZE

#define ECHO_GET_IMPULSE_RESPONSE_SIZE   27

ECHO_GET_SAMPLING_RATE

#define ECHO_GET_SAMPLING_RATE   25

ECHO_SET_SAMPLING_RATE

#define ECHO_SET_SAMPLING_RATE   24