SpeexPreprocessState: The Speex preprocessor


Defines
#define	SPEEX_PREPROCESS_SET_DENOISE 0
#define	SPEEX_PREPROCESS_GET_DENOISE 1
#define	SPEEX_PREPROCESS_SET_AGC 2
#define	SPEEX_PREPROCESS_GET_AGC 3
#define	SPEEX_PREPROCESS_SET_VAD 4
#define	SPEEX_PREPROCESS_GET_VAD 5
#define	SPEEX_PREPROCESS_SET_AGC_LEVEL 6
#define	SPEEX_PREPROCESS_GET_AGC_LEVEL 7
#define	SPEEX_PREPROCESS_SET_DEREVERB 8
#define	SPEEX_PREPROCESS_GET_DEREVERB 9
#define	SPEEX_PREPROCESS_SET_DEREVERB_LEVEL 10
#define	SPEEX_PREPROCESS_GET_DEREVERB_LEVEL 11
#define	SPEEX_PREPROCESS_SET_DEREVERB_DECAY 12
#define	SPEEX_PREPROCESS_GET_DEREVERB_DECAY 13
#define	SPEEX_PREPROCESS_SET_PROB_START 14
#define	SPEEX_PREPROCESS_GET_PROB_START 15
#define	SPEEX_PREPROCESS_SET_PROB_CONTINUE 16
#define	SPEEX_PREPROCESS_GET_PROB_CONTINUE 17
#define	SPEEX_PREPROCESS_SET_NOISE_SUPPRESS 18
#define	SPEEX_PREPROCESS_GET_NOISE_SUPPRESS 19
#define	SPEEX_PREPROCESS_SET_ECHO_SUPPRESS 20
#define	SPEEX_PREPROCESS_GET_ECHO_SUPPRESS 21
#define	SPEEX_PREPROCESS_SET_ECHO_SUPPRESS_ACTIVE 22
#define	SPEEX_PREPROCESS_GET_ECHO_SUPPRESS_ACTIVE 23
#define	SPEEX_PREPROCESS_SET_ECHO_STATE 24
#define	SPEEX_PREPROCESS_GET_ECHO_STATE 25
#define	SPEEX_PREPROCESS_SET_AGC_INCREMENT 26
#define	SPEEX_PREPROCESS_GET_AGC_INCREMENT 27
#define	SPEEX_PREPROCESS_SET_AGC_DECREMENT 28
#define	SPEEX_PREPROCESS_GET_AGC_DECREMENT 29
#define	SPEEX_PREPROCESS_SET_AGC_MAX_GAIN 30
#define	SPEEX_PREPROCESS_GET_AGC_MAX_GAIN 31
Typedefs
typedef SpeexPreprocessState_	SpeexPreprocessState
Functions
SpeexPreprocessState *	speex_preprocess_state_init (int frame_size, int sampling_rate)
void	speex_preprocess_state_destroy (SpeexPreprocessState *st)
int	speex_preprocess_run (SpeexPreprocessState st, spx_int16_t x)
int	speex_preprocess (SpeexPreprocessState st, spx_int16_t x, spx_int32_t *echo)
void	speex_preprocess_estimate_update (SpeexPreprocessState st, spx_int16_t x)
int	speex_preprocess_ctl (SpeexPreprocessState st, int request, void ptr)

Detailed Description

This is the Speex preprocessor. The preprocess can do noise suppression, residual echo suppression (after using the echo canceller), automatic gain control (AGC) and voice activity detection (VAD).

Define Documentation

#define SPEEX_PREPROCESS_GET_AGC 3

Get preprocessor Automatic Gain Control state

#define SPEEX_PREPROCESS_GET_AGC_DECREMENT 29

Get maximal gain decrease in dB/second (int32)

#define SPEEX_PREPROCESS_GET_AGC_INCREMENT 27

Get maximal gain increase in dB/second (int32)

#define SPEEX_PREPROCESS_GET_AGC_LEVEL 7

Get preprocessor Automatic Gain Control level

#define SPEEX_PREPROCESS_GET_AGC_MAX_GAIN 31

Get maximal gain in dB (int32)

#define SPEEX_PREPROCESS_GET_DENOISE 1

Get preprocessor denoiser state

#define SPEEX_PREPROCESS_GET_DEREVERB 9

Get preprocessor dereverb state

#define SPEEX_PREPROCESS_GET_DEREVERB_DECAY 13

Get preprocessor dereverb decay

#define SPEEX_PREPROCESS_GET_DEREVERB_LEVEL 11

Get preprocessor dereverb level

#define SPEEX_PREPROCESS_GET_ECHO_STATE 25

Get the corresponding echo canceller state

#define SPEEX_PREPROCESS_GET_ECHO_SUPPRESS 21

Get maximum attenuation of the residual echo in dB (negative number)

#define SPEEX_PREPROCESS_GET_ECHO_SUPPRESS_ACTIVE 23

Get maximum attenuation of the residual echo in dB when near end is active (negative number)

#define SPEEX_PREPROCESS_GET_NOISE_SUPPRESS 19

Get maximum attenuation of the noise in dB (negative number)

#define SPEEX_PREPROCESS_GET_PROB_CONTINUE 17

Get probability required for the VAD to stay in the voice state (integer percent)

#define SPEEX_PREPROCESS_GET_PROB_START 15

Get probability required for the VAD to go from silence to voice

#define SPEEX_PREPROCESS_GET_VAD 5

Get preprocessor Voice Activity Detection state

#define SPEEX_PREPROCESS_SET_AGC 2

Set preprocessor Automatic Gain Control state

#define SPEEX_PREPROCESS_SET_AGC_DECREMENT 28

Set maximal gain decrease in dB/second (int32)

#define SPEEX_PREPROCESS_SET_AGC_INCREMENT 26

Set maximal gain increase in dB/second (int32)

#define SPEEX_PREPROCESS_SET_AGC_LEVEL 6

Set preprocessor Automatic Gain Control level

#define SPEEX_PREPROCESS_SET_AGC_MAX_GAIN 30

Set maximal gain in dB (int32)

#define SPEEX_PREPROCESS_SET_DENOISE 0

Set preprocessor denoiser state

#define SPEEX_PREPROCESS_SET_DEREVERB 8

Set preprocessor dereverb state

#define SPEEX_PREPROCESS_SET_DEREVERB_DECAY 12

Set preprocessor dereverb decay

#define SPEEX_PREPROCESS_SET_DEREVERB_LEVEL 10

Set preprocessor dereverb level

#define SPEEX_PREPROCESS_SET_ECHO_STATE 24

Set the corresponding echo canceller state so that residual echo suppression can be performed (NULL for no residual echo suppression)

#define SPEEX_PREPROCESS_SET_ECHO_SUPPRESS 20

Set maximum attenuation of the residual echo in dB (negative number)

#define SPEEX_PREPROCESS_SET_ECHO_SUPPRESS_ACTIVE 22

Set maximum attenuation of the residual echo in dB when near end is active (negative number)

#define SPEEX_PREPROCESS_SET_NOISE_SUPPRESS 18

Set maximum attenuation of the noise in dB (negative number)

#define SPEEX_PREPROCESS_SET_PROB_CONTINUE 16

Set probability required for the VAD to stay in the voice state (integer percent)

#define SPEEX_PREPROCESS_SET_PROB_START 14

Set probability required for the VAD to go from silence to voice

#define SPEEX_PREPROCESS_SET_VAD 4

Set preprocessor Voice Activity Detection state

Typedef Documentation

typedef struct SpeexPreprocessState_ SpeexPreprocessState

State of the preprocessor (one per channel). Should never be accessed directly.

Function Documentation

int speex_preprocess	(	SpeexPreprocessState *	st,
		spx_int16_t *	x,
		spx_int32_t *	echo
	)

Preprocess a frame (deprecated, use speex_preprocess_run() instead)

int speex_preprocess_ctl	(	SpeexPreprocessState *	st,
		int	request,
		void *	ptr
	)

Used like the ioctl function to control the preprocessor parameters

Parameters:

	st	Preprocessor state
	request	ioctl-type request (one of the SPEEX_PREPROCESS_* macros)
	ptr	Data exchanged to-from function

Returns:: 0 if no error, -1 if request in unknown

void speex_preprocess_estimate_update	(	SpeexPreprocessState *	st,
		spx_int16_t *	x
	)

Update preprocessor state, but do not compute the output

Parameters:

	st	Preprocessor state
	x	Audio sample vector (in only). Must be same size as specified in speex_preprocess_state_init().

int speex_preprocess_run	(	SpeexPreprocessState *	st,
		spx_int16_t *	x
	)

Preprocess a frame

Parameters:

	st	Preprocessor state
	x	Audio sample vector (in and out). Must be same size as specified in speex_preprocess_state_init().

Returns:: Bool value for voice activity (1 for speech, 0 for noise/silence), ONLY if VAD turned on.

void speex_preprocess_state_destroy ( SpeexPreprocessState * st )

Destroys a preprocessor state

Parameters:

Preprocessor state to destroy

SpeexPreprocessState* speex_preprocess_state_init	(	int	frame_size,
		int	sampling_rate
	)

Creates a new preprocessing state. You MUST create one state per channel processed.

Parameters:

	frame_size	Number of samples to process at one time (should correspond to 10-20 ms). Must be the same value as that used for the echo canceller for residual echo cancellation to work.
	sampling_rate	Sampling rate used for the input.

Returns:: Newly created preprocessor state

Generated on Wed May 23 00:53:16 2007 for Speex by

1.5.1

SpeexPreprocessState: The Speex preprocessor

Defines

Typedefs

Functions

Detailed Description

Define Documentation

Typedef Documentation

Function Documentation