diff options
author | Paul Moore <pmoore@redhat.com> | 2014-06-17 17:30:23 -0400 |
---|---|---|
committer | Paul Moore <pmoore@redhat.com> | 2014-06-17 17:30:23 -0400 |
commit | 170b5910d9fbea79de1bb40df22eda5f98250c0c (patch) | |
tree | ca9560e878d2842d45c6f99077d0d8b8f8b0f9ba /drivers/misc/echo/oslec.h | |
parent | 47dd0b76ace953bd2c0479076db0d3e3b9594003 (diff) | |
parent | 1860e379875dfe7271c649058aeddffe5afd9d0d (diff) |
Merge tag 'v3.15' into next
Linux 3.15
Diffstat (limited to 'drivers/misc/echo/oslec.h')
-rw-r--r-- | drivers/misc/echo/oslec.h | 94 |
1 files changed, 94 insertions, 0 deletions
diff --git a/drivers/misc/echo/oslec.h b/drivers/misc/echo/oslec.h new file mode 100644 index 00000000000..f4175360ce2 --- /dev/null +++ b/drivers/misc/echo/oslec.h @@ -0,0 +1,94 @@ +/* + * 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. + * + * 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. + * + */ + +#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 */ |