mirror of
https://github.com/FEX-Emu/linux.git
synced 2024-12-22 01:10:28 +00:00
45 lines
1.5 KiB
C
45 lines
1.5 KiB
C
|
/* $Id: isdn_audio.h,v 1.1.2.2 2004/01/12 22:37:18 keil Exp $
|
||
|
|
*
|
||
|
|
* Linux ISDN subsystem, audio conversion and compression (linklevel).
|
||
|
|
*
|
||
|
|
* Copyright 1994-1999 by Fritz Elfert (fritz@isdn4linux.de)
|
||
|
|
*
|
||
|
|
* This software may be used and distributed according to the terms
|
||
|
|
* of the GNU General Public License, incorporated herein by reference.
|
||
|
|
*
|
||
|
|
*/
|
||
|
|
|
||
|
|
#define DTMF_NPOINTS 205 /* Number of samples for DTMF recognition */
|
||
|
|
typedef struct adpcm_state {
|
||
|
|
int a;
|
||
|
|
int d;
|
||
|
|
int word;
|
||
|
|
int nleft;
|
||
|
|
int nbits;
|
||
|
|
} adpcm_state;
|
||
|
|
|
||
|
|
typedef struct dtmf_state {
|
||
|
|
char last;
|
||
|
|
char llast;
|
||
|
|
int idx;
|
||
|
|
int buf[DTMF_NPOINTS];
|
||
|
|
} dtmf_state;
|
||
|
|
|
||
|
|
typedef struct silence_state {
|
||
|
|
int state;
|
||
|
|
unsigned int idx;
|
||
|
|
} silence_state;
|
||
|
|
|
||
|
|
extern void isdn_audio_ulaw2alaw(unsigned char *, unsigned long);
|
||
|
|
extern void isdn_audio_alaw2ulaw(unsigned char *, unsigned long);
|
||
|
|
extern adpcm_state *isdn_audio_adpcm_init(adpcm_state *, int);
|
||
|
|
extern int isdn_audio_adpcm2xlaw(adpcm_state *, int, unsigned char *, unsigned char *, int);
|
||
|
|
extern int isdn_audio_xlaw2adpcm(adpcm_state *, int, unsigned char *, unsigned char *, int);
|
||
|
|
extern void isdn_audio_calc_dtmf(modem_info *, unsigned char *, int, int);
|
||
|
|
extern void isdn_audio_eval_dtmf(modem_info *);
|
||
|
|
dtmf_state *isdn_audio_dtmf_init(dtmf_state *);
|
||
|
|
extern void isdn_audio_calc_silence(modem_info *, unsigned char *, int, int);
|
||
|
|
extern void isdn_audio_eval_silence(modem_info *);
|
||
|
|
silence_state *isdn_audio_silence_init(silence_state *);
|
||
|
|
extern void isdn_audio_put_dle_code(modem_info *, u_char);
|