spandsp 0.0.6
v18.h File Reference

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Typedefs

typedef struct v18_state_s v18_state_t

Enumerations

enum  {
  V18_MODE_NONE = 0 , V18_MODE_5BIT_45 = 1 , V18_MODE_5BIT_50 = 2 , V18_MODE_DTMF = 3 ,
  V18_MODE_EDT = 4 , V18_MODE_BELL103 = 5 , V18_MODE_V23VIDEOTEX = 6 , V18_MODE_V21TEXTPHONE = 7 ,
  V18_MODE_V18TEXTPHONE = 8
}

Functions

logging_state_tv18_get_logging_state (v18_state_t *s)
v18_state_tv18_init (v18_state_t *s, int calling_party, int mode, put_msg_func_t put_msg, void *user_data)
 Initialise a V.18 context.
int v18_release (v18_state_t *s)
 Release a V.18 context.
int v18_free (v18_state_t *s)
 Release a V.18 context.
 SPAN_DECLARE_NONSTD (int) v18_tx(v18_state_t *s
 Generate a block of V.18 audio samples.
int v18_put (v18_state_t *s, const char msg[], int len)
 Put a string to a V.18 context's input buffer.
int v18_encode_dtmf (v18_state_t *s, char dtmf[], const char msg[])
 Convert a text string to a V.18 DTMF string.
int v18_decode_dtmf (v18_state_t *s, char msg[], const char dtmf[])
 Convert a V.18 DTMF string to a text string.
uint16_t v18_encode_baudot (v18_state_t *s, uint8_t ch)
uint8_t v18_decode_baudot (v18_state_t *s, uint8_t ch)
const char * v18_mode_to_str (int mode)
 Return a short name for an V.18 mode.

Variables

int16_t amp []
int16_t int max_len
const int16_t int len

Function Documentation

◆ SPAN_DECLARE_NONSTD()

SPAN_DECLARE_NONSTD ( int )

Generate a block of V.18 audio samples.

Get the next bit of data from a T.38 rate adapting non-ECM buffer context.

Get a bit of received non-ECM image data.

Get the next bit of a transmitted serial bit stream.

Process a block of received V.18 audio samples.

Generate a block of V.18 audio samples.

Parameters
sThe V.18 context.
ampThe audio sample buffer.
max_lenThe number of samples to be generated.
Returns
The number of samples actually generated.

Process a block of received V.18 audio samples.

Parameters
sThe V.18 context.
ampThe audio sample buffer.
lenThe number of samples in the buffer.

◆ v18_decode_dtmf()

int v18_decode_dtmf ( v18_state_t * s,
char msg[],
const char dtmf[] )

Convert a V.18 DTMF string to a text string.

Convert a V.18 DTMF string to a text string.

Parameters
sThe V.18 context.
msgThe resulting test string.
dtmfThe DTMF string to be converted.
Returns
The length of the text string.

◆ v18_encode_dtmf()

int v18_encode_dtmf ( v18_state_t * s,
char dtmf[],
const char msg[] )

Convert a text string to a V.18 DTMF string.

Convert a text string to a V.18 DTMF string.

Parameters
sThe V.18 context.
dtmfThe resulting DTMF string.
msgThe text string to be converted.
Returns
The length of the DTMF string.

◆ v18_free()

int v18_free ( v18_state_t * s)

Release a V.18 context.

Free a V.18 context.

Parameters
sThe V.18 context.
Returns
0 for OK.

◆ v18_init()

v18_state_t * v18_init ( v18_state_t * s,
int calling_party,
int mode,
put_msg_func_t put_msg,
void * user_data )

Initialise a V.18 context.

Initialise a V.18 context.

Parameters
sThe V.18 context.
calling_partyTRUE if caller mode, else answerer mode.
modeMode of operation.
put_msgA callback routine called to deliver the received text to the application.
user_dataAn opaque pointer for the callback routine.
Returns
A pointer to the V.18 context, or NULL if there was a problem.

References ASYNC_PARITY_EVEN, ASYNC_PARITY_NONE, async_tx_init(), v18_state_s::calling_party, dtmf_rx_init(), dtmf_tx_init(), fsk_rx_init(), fsk_tx_init(), queue_init(), QUEUE_READ_ATOMIC, and QUEUE_WRITE_ATOMIC.

◆ v18_mode_to_str()

const char * v18_mode_to_str ( int mode)

Return a short name for an V.18 mode.

Parameters
modeThe code for the V.18 mode.
Returns
A pointer to the name.

◆ v18_put()

int v18_put ( v18_state_t * s,
const char msg[],
int len )

Put a string to a V.18 context's input buffer.

Parameters
sThe V.18 context.
msgThe string to be added.
lenThe length of the string. If negative, the string is assumed to be a NULL terminated string.
Returns
The number of characters actually added. This may be less than the length of the digit string, if the buffer fills up. If the string is invalid, this function will return -1.

References queue_write().

◆ v18_release()

int v18_release ( v18_state_t * s)

Release a V.18 context.

Release a V.18 context.

Parameters
sThe V.18 context.
Returns
0 for OK.