libspandsp 0.0.4

g711.h File Reference

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Classes

struct  g711_state_t

Defines

#define G711_ALAW_IDLE_OCTET   0x5D
#define G711_ULAW_IDLE_OCTET   0xFF
#define ULAW_BIAS   0x84
#define ALAW_AMI_MASK   0x55

Enumerations

enum  { G711_ALAW = 0, G711_ULAW }

Functions

uint8_t alaw_to_ulaw (uint8_t alaw)
 Transcode from A-law to u-law, using the procedure defined in G.711.
uint8_t ulaw_to_alaw (uint8_t ulaw)
 Transcode from u-law to A-law, using the procedure defined in G.711.
int g711_decode (g711_state_t *s, int16_t amp[], const uint8_t g711_data[], int g711_bytes)
int g711_encode (g711_state_t *s, uint8_t g711_data[], const int16_t amp[], int len)
int g711_transcode (g711_state_t *s, uint8_t g711_out[], const uint8_t g711_in[], int g711_bytes)
g711_state_tg711_init (g711_state_t *s, int mode)
int g711_release (g711_state_t *s)

Detailed Description


Function Documentation

uint8_t alaw_to_ulaw ( uint8_t  alaw)

Transcode from A-law to u-law, using the procedure defined in G.711.

Parameters:
alawThe A-law sample to transcode.
Returns:
The best matching u-law value.
g711_state_t* g711_init ( g711_state_t s,
int  mode 
)

Initialise a G.711 encode or decode context.

Parameters:
sThe G.711 context.
modeThe G.711 mode.
Returns:
A pointer to the G.711 context, or NULL for error.

References g711_state_t::mode.

int g711_release ( g711_state_t s)

Free a G.711 encode or decode context.

Parameters:
sThe G.711 context.
Returns:
0 for OK.
uint8_t ulaw_to_alaw ( uint8_t  ulaw)

Transcode from u-law to A-law, using the procedure defined in G.711.

Parameters:
ulawThe u-law sample to transcode.
Returns:
The best matching A-law value.