spandsp  0.0.6
fax.h File Reference

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Typedefs

typedef struct fax_state_s fax_state_t
 

Functions

 SPAN_DECLARE_NONSTD (int) fax_rx(fax_state_t *s
 Apply T.30 receive processing to a block of audio samples. More...
 
void fax_set_transmit_on_idle (fax_state_t *s, int transmit_on_idle)
 Select whether silent audio will be sent when FAX transmit is idle. More...
 
void fax_set_tep_mode (fax_state_t *s, int use_tep)
 Select whether TEP will be sent for the image modems. More...
 
t30_state_tfax_get_t30_state (fax_state_t *s)
 Get a pointer to the T.30 engine associated with a FAX context. More...
 
logging_state_tfax_get_logging_state (fax_state_t *s)
 Get a pointer to the logging context associated with a FAX context. More...
 
int fax_restart (fax_state_t *s, int calling_party)
 Restart a FAX context. More...
 
fax_state_tfax_init (fax_state_t *s, int calling_party)
 Initialise a FAX context. More...
 
int fax_release (fax_state_t *s)
 Release a FAX context. More...
 
int fax_free (fax_state_t *s)
 Free a FAX context. More...
 

Variables

int16_t * amp
 
int16_t int len
 
int16_t int max_len
 

Function Documentation

◆ fax_free()

int fax_free ( fax_state_t s)

Free a FAX context.

Free a FAX context.

Parameters
sThe FAX context.
Returns
0 for OK, else -1.

References fax_state_s::t30, and t30_release().

◆ fax_get_logging_state()

logging_state_t* fax_get_logging_state ( fax_state_t s)

Get a pointer to the logging context associated with a FAX context.

Get a pointer to the logging context associated with a FAX context.

Parameters
sThe FAX context.
Returns
A pointer to the logging context, or NULL.

References fax_state_s::logging.

◆ fax_get_t30_state()

t30_state_t* fax_get_t30_state ( fax_state_t s)

Get a pointer to the T.30 engine associated with a FAX context.

Get a pointer to the T.30 engine associated with a FAX context.

Parameters
sThe FAX context.
Returns
A pointer to the T.30 context, or NULL.

References fax_state_s::t30.

◆ fax_init()

fax_state_t* fax_init ( fax_state_t s,
int  calling_party 
)

Initialise a FAX context.

Initialise a FAX context.

Parameters
sThe FAX context.
calling_partyTRUE if the context is for a calling party. FALSE if the context is for an answering party.
Returns
A pointer to the FAX context, or NULL if there was a problem.

◆ fax_release()

int fax_release ( fax_state_t s)

Release a FAX context.

Release a FAX context.

Parameters
sThe FAX context.
Returns
0 for OK, else -1.

References fax_state_s::t30, and t30_release().

◆ fax_restart()

int fax_restart ( fax_state_t s,
int  calling_party 
)

Restart a FAX context.

Restart a FAX context.

Parameters
sThe FAX context.
calling_partyTRUE if the context is for a calling party. FALSE if the context is for an answering party.
Returns
0 for OK, else -1.

◆ fax_set_tep_mode()

void fax_set_tep_mode ( fax_state_t s,
int  use_tep 
)

Select whether TEP will be sent for the image modems.

Select whether talker echo protection tone will be sent for the image modems.

Parameters
sThe FAX context.
use_tepTRUE if TEP should be sent.

◆ fax_set_transmit_on_idle()

void fax_set_transmit_on_idle ( fax_state_t s,
int  transmit_on_idle 
)

Select whether silent audio will be sent when FAX transmit is idle.

Select whether silent audio will be sent when FAX transmit is idle.

Parameters
sThe FAX context.
transmit_on_idleTRUE if silent audio should be output when the FAX transmitter is idle. FALSE to transmit zero length audio when the FAX transmitter is idle. The default behaviour is FALSE.

References fax_state_s::modems, and fax_modems_state_s::transmit_on_idle.

◆ SPAN_DECLARE_NONSTD()

SPAN_DECLARE_NONSTD ( int  )

Apply T.30 receive processing to a block of 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.

Apply T.30 transmit processing to generate a block of audio samples.

Apply fake T.30 receive processing.

Apply T.30 receive processing to a block of audio samples.

Parameters
sThe FAX context.
ampThe audio sample buffer.
lenThe number of samples in the buffer.
Returns
The number of samples unprocessed. This should only be non-zero if the software has reached the end of the FAX call.

Apply fake T.30 receive processing when a block of audio samples is missing (e.g due to packet loss).

Parameters
sThe FAX context.
lenThe number of samples to fake.
Returns
The number of samples unprocessed. This should only be non-zero if the software has reached the end of the FAX call.

Apply T.30 transmit processing to generate a block of audio samples.

Parameters
sThe FAX context.
ampThe audio sample buffer.
max_lenThe number of samples to be generated.
Returns
The number of samples actually generated. This will be zero when there is nothing to send.