isdn_audio.c File Reference

#include <linux/isdn.h>
#include <linux/slab.h>
#include "isdn_audio.h"
#include "isdn_common.h"

Go to the source code of this file.

Macros
#define	NCOEFF   8 /* number of frequencies to be analyzed */
#define	DTMF_TRESH   4000 /* above this is dtmf */
#define	SILENCE_TRESH   200 /* below this is silence */
#define	AMP_BITS   9 /* bits per sample, reduced to avoid overflow */
#define	LOGRP   0
#define	HIGRP   1
#define	ZEROTRAP   /* turn on the trap as per the MIL-STD */
#define	BIAS   0x84 /* define the add-in bias for 16 bit samples */
#define	CLIP   32635

Functions
void	isdn_audio_ulaw2alaw (unsigned char *buff, unsigned long len)
void	isdn_audio_alaw2ulaw (unsigned char *buff, unsigned long len)
adpcm_state *	isdn_audio_adpcm_init (adpcm_state *s, int nbits)
dtmf_state *	isdn_audio_dtmf_init (dtmf_state *s)
int	isdn_audio_adpcm2xlaw (adpcm_state *s, int fmt, unsigned char *in, unsigned char *out, int len)
int	isdn_audio_xlaw2adpcm (adpcm_state *s, int fmt, unsigned char *in, unsigned char *out, int len)
void	isdn_audio_eval_dtmf (modem_info *info)
void	isdn_audio_calc_dtmf (modem_info *info, unsigned char *buf, int len, int fmt)
silence_state *	isdn_audio_silence_init (silence_state *s)
void	isdn_audio_calc_silence (modem_info *info, unsigned char *buf, int len, int fmt)
void	isdn_audio_put_dle_code (modem_info *info, u_char code)
void	isdn_audio_eval_silence (modem_info *info)

Variables
char *	isdn_audio_revision = "$Revision: 1.1.2.2 $"

Macro Definition Documentation

#define AMP_BITS   9 /* bits per sample, reduced to avoid overflow */

Definition at line 176 of file isdn_audio.c.

#define BIAS   0x84 /* define the add-in bias for 16 bit samples */

Definition at line 238 of file isdn_audio.c.

#define CLIP   32635

Definition at line 239 of file isdn_audio.c.

#define DTMF_TRESH   4000 /* above this is dtmf */

Definition at line 174 of file isdn_audio.c.

#define HIGRP   1

Definition at line 178 of file isdn_audio.c.

#define LOGRP   0

Definition at line 177 of file isdn_audio.c.

#define NCOEFF   8 /* number of frequencies to be analyzed */

Definition at line 173 of file isdn_audio.c.

#define SILENCE_TRESH   200 /* below this is silence */

Definition at line 175 of file isdn_audio.c.

#define ZEROTRAP   /* turn on the trap as per the MIL-STD */

Definition at line 236 of file isdn_audio.c.

Function Documentation

int isdn_audio_adpcm2xlaw	(	adpcm_state *	s,
		int	fmt,
		unsigned char *	in,
		unsigned char *	out,
		int	len
	)

Definition at line 361 of file isdn_audio.c.

adpcm_state* isdn_audio_adpcm_init	(	adpcm_state *	s,
		int	nbits
	)

Definition at line 329 of file isdn_audio.c.

void isdn_audio_alaw2ulaw	(	unsigned char *	buff,
		unsigned long	len
	)

Definition at line 223 of file isdn_audio.c.

void isdn_audio_calc_dtmf	(	modem_info *	info,
		unsigned char *	buf,
		int	len,
		int	fmt
	)

Definition at line 593 of file isdn_audio.c.

void isdn_audio_calc_silence	(	modem_info *	info,
		unsigned char *	buf,
		int	len,
		int	fmt
	)

Definition at line 634 of file isdn_audio.c.

dtmf_state* isdn_audio_dtmf_init

(

dtmf_state *

s

)

Definition at line 344 of file isdn_audio.c.

void isdn_audio_eval_dtmf

(

modem_info *

info

)

Definition at line 495 of file isdn_audio.c.

void isdn_audio_eval_silence

(

modem_info *

info

)

Definition at line 691 of file isdn_audio.c.

void isdn_audio_put_dle_code	(	modem_info *	info,
		u_char	code
	)

Definition at line 661 of file isdn_audio.c.

silence_state* isdn_audio_silence_init

(

silence_state *

s

)

Definition at line 622 of file isdn_audio.c.

void isdn_audio_ulaw2alaw	(	unsigned char *	buff,
		unsigned long	len
	)

Definition at line 217 of file isdn_audio.c.

int isdn_audio_xlaw2adpcm	(	adpcm_state *	s,
		int	fmt,
		unsigned char *	in,
		unsigned char *	out,
		int	len
	)

Definition at line 396 of file isdn_audio.c.

Variable Documentation

char* isdn_audio_revision = "$Revision: 1.1.2.2 $"

Definition at line 19 of file isdn_audio.c.