/* SPDX-License-Identifier: GPL-2.0-only */
|
/*
|
* OSLEC - A line echo canceller. This code is being developed
|
* against and partially complies with G168. Using code from SpanDSP
|
*
|
* Written by Steve Underwood <steveu@coppice.org>
|
* and David Rowe <david_at_rowetel_dot_com>
|
*
|
* Copyright (C) 2001 Steve Underwood and 2007-2008 David Rowe
|
*
|
* All rights reserved.
|
*/
|
|
#ifndef __OSLEC_H
|
#define __OSLEC_H
|
|
/* Mask bits for the adaption mode */
|
#define ECHO_CAN_USE_ADAPTION 0x01
|
#define ECHO_CAN_USE_NLP 0x02
|
#define ECHO_CAN_USE_CNG 0x04
|
#define ECHO_CAN_USE_CLIP 0x08
|
#define ECHO_CAN_USE_TX_HPF 0x10
|
#define ECHO_CAN_USE_RX_HPF 0x20
|
#define ECHO_CAN_DISABLE 0x40
|
|
/**
|
* oslec_state: G.168 echo canceller descriptor.
|
*
|
* This defines the working state for a line echo canceller.
|
*/
|
struct oslec_state;
|
|
/**
|
* oslec_create - Create a voice echo canceller context.
|
* @len: The length of the canceller, in samples.
|
* @return: The new canceller context, or NULL if the canceller could not be
|
* created.
|
*/
|
struct oslec_state *oslec_create(int len, int adaption_mode);
|
|
/**
|
* oslec_free - Free a voice echo canceller context.
|
* @ec: The echo canceller context.
|
*/
|
void oslec_free(struct oslec_state *ec);
|
|
/**
|
* oslec_flush - Flush (reinitialise) a voice echo canceller context.
|
* @ec: The echo canceller context.
|
*/
|
void oslec_flush(struct oslec_state *ec);
|
|
/**
|
* oslec_adaption_mode - set the adaption mode of a voice echo canceller context.
|
* @ec The echo canceller context.
|
* @adaption_mode: The mode.
|
*/
|
void oslec_adaption_mode(struct oslec_state *ec, int adaption_mode);
|
|
void oslec_snapshot(struct oslec_state *ec);
|
|
/**
|
* oslec_update: Process a sample through a voice echo canceller.
|
* @ec: The echo canceller context.
|
* @tx: The transmitted audio sample.
|
* @rx: The received audio sample.
|
*
|
* The return value is the clean (echo cancelled) received sample.
|
*/
|
int16_t oslec_update(struct oslec_state *ec, int16_t tx, int16_t rx);
|
|
/**
|
* oslec_hpf_tx: Process to high pass filter the tx signal.
|
* @ec: The echo canceller context.
|
* @tx: The transmitted auio sample.
|
*
|
* The return value is the HP filtered transmit sample, send this to your D/A.
|
*/
|
int16_t oslec_hpf_tx(struct oslec_state *ec, int16_t tx);
|
|
#endif /* __OSLEC_H */
|
