plc.c File Reference

#include <stdio.h>
#include <inttypes.h>
#include <stdlib.h>
#include <string.h>
#include "floating_fudge.h"
#include <limits.h>
#include "spandsp/telephony.h"
#include "spandsp/saturated.h"
#include "spandsp/plc.h"

Defines
#define	ATTENUATION_INCREMENT   0.0025f
#define	ms_to_samples(t)   (((t)*SAMPLE_RATE)/1000)
Functions
int	plc_rx (plc_state_t *s, int16_t amp[], int len)
	Process a block of received audio samples for PLC.
int	plc_fillin (plc_state_t *s, int16_t amp[], int len)
	Fill-in a block of missing audio samples.
plc_state_t *	plc_init (plc_state_t *s)
	Initialise a PLC context.
int	plc_free (plc_state_t *s)

---

Detailed Description

---

Function Documentation

int plc_fillin	(	plc_state_t *	s,
		int16_t	amp[],
		int	len
	)

Fill-in a block of missing audio samples.

Fill-in a block of missing audio samples.

Parameters:

	s	The packet loss concealer context.
	amp	The audio sample buffer.
	len	The number of samples to be synthesised.

Returns:

The number of samples synthesized.

References CORRELATION_SPAN, plc_state_t::history, plc_state_t::missing_samples, plc_state_t::pitch, plc_state_t::pitch_offset, plc_state_t::pitchbuf, PLC_HISTORY_LEN, PLC_PITCH_MAX, and PLC_PITCH_MIN.

int plc_free

(

plc_state_t *

s

)

Free a packet loss concealer context.

Parameters:

s

The packet loss concealer context.

Returns:

0 for OK.

plc_state_t* plc_init

(

plc_state_t *

s

)

Initialise a PLC context.

Initialise a packet loss concealer context.

Parameters:

s

The packet loss concealer context.

Returns:

A pointer to the the packet loss concealer context.

int plc_rx	(	plc_state_t *	s,
		int16_t	amp[],
		int	len
	)

Process a block of received audio samples for PLC.

Process a block of received audio samples for PLC.

Parameters:

	s	The packet loss concealer context.
	amp	The audio sample buffer.
	len	The number of samples in the buffer.

Returns:

The number of samples in the buffer.

References plc_state_t::missing_samples, plc_state_t::pitch, plc_state_t::pitch_offset, and plc_state_t::pitchbuf.