echo_david.h File Reference

#include "fir.h"

Go to the source code of this file.

Classes
struct	echo_can_state_t
Enumerations
enum	{   ECHO_CAN_USE_ADAPTION = 0x01, ECHO_CAN_USE_NLP = 0x02, ECHO_CAN_USE_CNG = 0x04, ECHO_CAN_USE_CLIP = 0x08,   ECHO_CAN_USE_SUPPRESSOR = 0x10, ECHO_CAN_USE_TX_HPF = 0x20, ECHO_CAN_USE_RX_HPF = 0x40, ECHO_CAN_DISABLE = 0x80 }
Functions
echo_can_state_t *	echo_can_create (int len, int adaption_mode)
void	echo_can_free (echo_can_state_t *ec)
void	echo_can_flush (echo_can_state_t *ec)
void	echo_can_adaption_mode (echo_can_state_t *ec, int adaption_mode)
int16_t	echo_can_update (echo_can_state_t *ec, int16_t tx, int16_t rx)
int16_t	echo_can_hpf_tx (echo_can_state_t *ec, int16_t tx)
void	echo_can_snapshot (echo_can_state_t *ec)

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Detailed Description

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Function Documentation

void echo_can_adaption_mode	(	echo_can_state_t *	ec,
		int	adaption_mode
	)

Set the adaption mode of a voice echo canceller context.

Parameters:

	ec	The echo canceller context.
	adaption_mode	The mode.

References echo_can_state_t::adaption_mode.

Referenced by echo_can_create().

echo_can_state_t* echo_can_create	(	int	len,
		int	adaption_mode
	)

Create a voice echo canceller context.

Parameters:

len

The length of the canceller, in samples.

Returns:

The new canceller context, or NULL if the canceller could not be created.

References echo_can_state_t::cng_level, echo_can_state_t::cond_met, echo_can_state_t::curr_pos, echo_can_state_t::dtd_onset, echo_can_adaption_mode(), echo_can_state_t::fir_state, echo_can_state_t::fir_state_bg, echo_can_state_t::fir_taps16, echo_can_state_t::fir_taps32, echo_can_state_t::geigel_lag, echo_can_state_t::geigel_max, echo_can_state_t::Lbgn, echo_can_state_t::Lbgn_acc, echo_can_state_t::Lbgn_upper, echo_can_state_t::Lbgn_upper_acc, echo_can_state_t::Lclean, echo_can_state_t::Lclean_bg, echo_can_state_t::Lclean_bgacc, echo_can_state_t::Lcleanacc, echo_can_state_t::log2taps, echo_can_state_t::Lrx, echo_can_state_t::Lrxacc, echo_can_state_t::Ltx, echo_can_state_t::Ltxacc, echo_can_state_t::Pstates, echo_can_state_t::rx_hpf, echo_can_state_t::rx_power_threshold, echo_can_state_t::snapshot, echo_can_state_t::tap_mask, echo_can_state_t::tap_rotate_counter, echo_can_state_t::tap_set, echo_can_state_t::taps, and echo_can_state_t::tx_hpf.

void echo_can_flush

(

echo_can_state_t *

ec

)

Flush (reinitialise) a voice echo canceller context.

Parameters:

ec

The echo canceller context.

References echo_can_state_t::clean_rx_power, echo_can_state_t::cng_filter, echo_can_state_t::cng_level, echo_can_state_t::curr_pos, fir16_state_t::curr_pos, echo_can_state_t::dtd_onset, echo_can_state_t::fir_state, echo_can_state_t::fir_state_bg, echo_can_state_t::fir_taps16, echo_can_state_t::fir_taps32, echo_can_state_t::geigel_lag, echo_can_state_t::geigel_max, echo_can_state_t::last_acf, echo_can_state_t::latest_correction, echo_can_state_t::Lbgn, echo_can_state_t::Lbgn_acc, echo_can_state_t::Lbgn_upper, echo_can_state_t::Lbgn_upper_acc, echo_can_state_t::Lclean, echo_can_state_t::Lclean_bg, echo_can_state_t::Lclean_bgacc, echo_can_state_t::Lcleanacc, echo_can_state_t::Lrx, echo_can_state_t::Lrxacc, echo_can_state_t::Ltx, echo_can_state_t::Ltxacc, echo_can_state_t::narrowband_count, echo_can_state_t::narrowband_score, echo_can_state_t::nonupdate_dwell, echo_can_state_t::Pstates, echo_can_state_t::rx_hpf, echo_can_state_t::rx_power, echo_can_state_t::supp1, echo_can_state_t::supp2, echo_can_state_t::supp_test1, echo_can_state_t::supp_test2, echo_can_state_t::tap_rotate_counter, echo_can_state_t::tap_set, echo_can_state_t::taps, echo_can_state_t::tx_hpf, echo_can_state_t::tx_power, and echo_can_state_t::vad.

void echo_can_free

(

echo_can_state_t *

ec

)

Free a voice echo canceller context.

Parameters:

ec

The echo canceller context.

References echo_can_state_t::fir_state, echo_can_state_t::fir_state_bg, echo_can_state_t::fir_taps16, echo_can_state_t::fir_taps32, and echo_can_state_t::snapshot.

int16_t echo_can_hpf_tx	(	echo_can_state_t *	ec,
		int16_t	tx
	)

Process to high pass filter the tx signal.

Parameters:

	ec	The echo canceller context.
	tx	The transmitted auio sample.

Returns:

The HP filtered transmit sample, send this to your D/A.

References echo_can_state_t::adaption_mode, and echo_can_state_t::tx_hpf.

int16_t echo_can_update	(	echo_can_state_t *	ec,
		int16_t	tx,
		int16_t	rx
	)

Process a sample through a voice echo canceller.

Parameters:

	ec	The echo canceller context.
	tx	The transmitted audio sample.
	rx	The received audio sample.

Returns:

The clean (echo cancelled) received sample.

References echo_can_state_t::adapt, echo_can_state_t::adaption_mode, echo_can_state_t::clean, echo_can_state_t::clean_nlp, echo_can_state_t::clean_rx_power, echo_can_state_t::cng, echo_can_state_t::cng_filter, echo_can_state_t::cng_level, echo_can_state_t::cng_rndnum, fir16_state_t::coeffs, echo_can_state_t::cond_met, fir16_state_t::curr_pos, echo_can_state_t::curr_pos, echo_can_state_t::dtd_onset, echo_can_state_t::factor, echo_can_state_t::fir_state, echo_can_state_t::fir_state_bg, echo_can_state_t::fir_taps16, echo_can_state_t::fir_taps32, fir16_state_t::history, echo_can_state_t::latest_correction, echo_can_state_t::Lbgn, echo_can_state_t::Lbgn_acc, echo_can_state_t::Lclean, echo_can_state_t::Lclean_bg, echo_can_state_t::Lclean_bgacc, echo_can_state_t::Lcleanacc, echo_can_state_t::log2taps, echo_can_state_t::Lrx, echo_can_state_t::Lrxacc, echo_can_state_t::Ltx, echo_can_state_t::Ltxacc, echo_can_state_t::narrowband_count, echo_can_state_t::narrowband_score, echo_can_state_t::nonupdate_dwell, echo_can_state_t::Pstates, echo_can_state_t::rx, echo_can_state_t::rx_hpf, echo_can_state_t::rx_power, echo_can_state_t::shift, echo_can_state_t::supp1, echo_can_state_t::supp2, echo_can_state_t::supp_test1, echo_can_state_t::supp_test2, echo_can_state_t::tap_mask, echo_can_state_t::tap_rotate_counter, echo_can_state_t::tap_set, echo_can_state_t::taps, echo_can_state_t::tx, echo_can_state_t::tx_power, and echo_can_state_t::vad.