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![Thomas Gleixner](/assets/img/avatar_default.png)
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not write to the free software foundation inc 675 mass ave cambridge ma 02139 usa extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 44 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Steve Winslow <swinslow@gmail.com> Reviewed-by: Alexios Zavras <alexios.zavras@intel.com> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190528170025.980374610@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
81 lines
2.2 KiB
C
81 lines
2.2 KiB
C
/* SPDX-License-Identifier: GPL-2.0-only */
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/*
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* OSLEC - A line echo canceller. This code is being developed
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* against and partially complies with G168. Using code from SpanDSP
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*
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* Written by Steve Underwood <steveu@coppice.org>
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* and David Rowe <david_at_rowetel_dot_com>
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*
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* Copyright (C) 2001 Steve Underwood and 2007-2008 David Rowe
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*
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* All rights reserved.
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*/
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#ifndef __OSLEC_H
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#define __OSLEC_H
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/* Mask bits for the adaption mode */
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#define ECHO_CAN_USE_ADAPTION 0x01
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#define ECHO_CAN_USE_NLP 0x02
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#define ECHO_CAN_USE_CNG 0x04
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#define ECHO_CAN_USE_CLIP 0x08
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#define ECHO_CAN_USE_TX_HPF 0x10
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#define ECHO_CAN_USE_RX_HPF 0x20
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#define ECHO_CAN_DISABLE 0x40
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/**
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* oslec_state: G.168 echo canceller descriptor.
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*
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* This defines the working state for a line echo canceller.
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*/
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struct oslec_state;
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/**
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* oslec_create - Create a voice echo canceller context.
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* @len: The length of the canceller, in samples.
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* @return: The new canceller context, or NULL if the canceller could not be
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* created.
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*/
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struct oslec_state *oslec_create(int len, int adaption_mode);
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/**
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* oslec_free - Free a voice echo canceller context.
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* @ec: The echo canceller context.
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*/
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void oslec_free(struct oslec_state *ec);
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/**
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* oslec_flush - Flush (reinitialise) a voice echo canceller context.
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* @ec: The echo canceller context.
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*/
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void oslec_flush(struct oslec_state *ec);
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/**
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* oslec_adaption_mode - set the adaption mode of a voice echo canceller context.
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* @ec The echo canceller context.
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* @adaption_mode: The mode.
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*/
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void oslec_adaption_mode(struct oslec_state *ec, int adaption_mode);
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void oslec_snapshot(struct oslec_state *ec);
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/**
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* oslec_update: Process a sample through a voice echo canceller.
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* @ec: The echo canceller context.
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* @tx: The transmitted audio sample.
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* @rx: The received audio sample.
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*
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* The return value is the clean (echo cancelled) received sample.
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*/
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int16_t oslec_update(struct oslec_state *ec, int16_t tx, int16_t rx);
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/**
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* oslec_hpf_tx: Process to high pass filter the tx signal.
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* @ec: The echo canceller context.
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* @tx: The transmitted auio sample.
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*
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* The return value is the HP filtered transmit sample, send this to your D/A.
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*/
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int16_t oslec_hpf_tx(struct oslec_state *ec, int16_t tx);
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#endif /* __OSLEC_H */
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