projects / linux-2.6-block.git / blame
| Commit | Line | Data |
|---|---|---|
| 1da177e4 LT |
1 | /* $Id: isdn_audio.h,v 1.1.2.2 2004/01/12 22:37:18 keil Exp $ |
| 2 | * | |
| 3 | * Linux ISDN subsystem, audio conversion and compression (linklevel). | |
| 4 | * | |
| 5 | * Copyright 1994-1999 by Fritz Elfert (fritz@isdn4linux.de) | |
| 6 | * | |
| 7 | * This software may be used and distributed according to the terms | |
| 8 | * of the GNU General Public License, incorporated herein by reference. | |
| 9 | * | |
| 10 | */ | |
| 11 | ||
| 12 | #define DTMF_NPOINTS 205 /* Number of samples for DTMF recognition */ | |
| 13 | typedef struct adpcm_state { | |
| 14 | int a; | |
| 15 | int d; | |
| 16 | int word; | |
| 17 | int nleft; | |
| 18 | int nbits; | |
| 19 | } adpcm_state; | |
| 20 | ||
| 21 | typedef struct dtmf_state { | |
| 22 | char last; | |
| 23 | char llast; | |
| 24 | int idx; | |
| 25 | int buf[DTMF_NPOINTS]; | |
| 26 | } dtmf_state; | |
| 27 | ||
| 28 | typedef struct silence_state { | |
| 29 | int state; | |
| 30 | unsigned int idx; | |
| 31 | } silence_state; | |
| 32 | ||
| 33 | extern void isdn_audio_ulaw2alaw(unsigned char *, unsigned long); | |
| 34 | extern void isdn_audio_alaw2ulaw(unsigned char *, unsigned long); | |
| 35 | extern adpcm_state *isdn_audio_adpcm_init(adpcm_state *, int); | |
| 36 | extern int isdn_audio_adpcm2xlaw(adpcm_state *, int, unsigned char *, unsigned char *, int); | |
| 37 | extern int isdn_audio_xlaw2adpcm(adpcm_state *, int, unsigned char *, unsigned char *, int); | |
| 1da177e4 LT |
38 | extern void isdn_audio_calc_dtmf(modem_info *, unsigned char *, int, int); |
| 39 | extern void isdn_audio_eval_dtmf(modem_info *); | |
| 40 | dtmf_state *isdn_audio_dtmf_init(dtmf_state *); | |
| 41 | extern void isdn_audio_calc_silence(modem_info *, unsigned char *, int, int); | |
| 42 | extern void isdn_audio_eval_silence(modem_info *); | |
| 43 | silence_state *isdn_audio_silence_init(silence_state *); | |
| 44 | extern void isdn_audio_put_dle_code(modem_info *, u_char); |