t38_non_ecm_buffer.h File Reference

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Classes
struct	t38_non_ecm_buffer_state_t
	A flow controlled non-ECM image data buffer, for buffering T.38 to analogue modem data. More...
Defines
#define	_SPANDSP_T38_NON_ECM_BUFFER_H_
#define	T38_NON_ECM_TX_BUF_LEN   16384
Functions
t38_non_ecm_buffer_state_t *	t38_non_ecm_buffer_init (t38_non_ecm_buffer_state_t *s, int mode, int min_row_bits)
	Initialise a T.38 rate adapting non-ECM buffer context.
void	t38_non_ecm_buffer_set_mode (t38_non_ecm_buffer_state_t *s, int mode, int min_row_bits)
	Set the mode of a T.38 rate adapting non-ECM buffer context.
void	t38_non_ecm_buffer_inject (t38_non_ecm_buffer_state_t *s, const uint8_t *buf, int len)
	Inject data to T.38 rate adapting non-ECM buffer context.
void	t38_non_ecm_buffer_push (t38_non_ecm_buffer_state_t *s)
	Inform a T.38 rate adapting non-ECM buffer context that the incoming data has finished, and the contents of the buffer should be played out as quickly as possible.
void	t38_non_ecm_buffer_report_input_status (t38_non_ecm_buffer_state_t *s, logging_state_t *logging)
	Report the input status of a T.38 rate adapting non-ECM buffer context to the specified logging context.
void	t38_non_ecm_buffer_report_output_status (t38_non_ecm_buffer_state_t *s, logging_state_t *logging)
	Report the output status of a T.38 rate adapting non-ECM buffer context to the specified logging context.
int	t38_non_ecm_buffer_get_bit (void *user_data)
	Get the next bit of data from a T.38 rate adapting non-ECM buffer context.

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Detailed Description

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Define Documentation

#define T38_NON_ECM_TX_BUF_LEN   16384

The buffer length much be a power of two. The chosen length is big enough for over 9s of data at the V.17 14,400bps rate.

Referenced by t38_non_ecm_buffer_get_bit(), and t38_non_ecm_buffer_inject().

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Function Documentation

int t38_non_ecm_buffer_get_bit

(

void *

user_data

)

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

Parameters:

user_data

The buffer context, cast to a void pointer.

Returns:

The next bit, or one of the values indicating a change of modem status.

References t38_non_ecm_buffer_state_t::bit_no, t38_non_ecm_buffer_state_t::data, t38_non_ecm_buffer_state_t::data_finished, t38_non_ecm_buffer_state_t::flow_control_fill_octet, t38_non_ecm_buffer_state_t::flow_control_fill_octets, t38_non_ecm_buffer_state_t::latest_eol_ptr, t38_non_ecm_buffer_state_t::octet, t38_non_ecm_buffer_state_t::out_octets, t38_non_ecm_buffer_state_t::out_ptr, SIG_STATUS_END_OF_DATA, and T38_NON_ECM_TX_BUF_LEN.

t38_non_ecm_buffer_state_t* t38_non_ecm_buffer_init	(	t38_non_ecm_buffer_state_t *	s,
		int	mode,
		int	min_row_bits
	)

Initialise a T.38 rate adapting non-ECM buffer context.

Parameters:

	s	The buffer context.
	mode	TRUE for image data mode, or FALSE for TCF mode.
	bits	The minimum number of bits per FAX image row.

Returns:

A pointer to the buffer context, or NULL if there was a problem.

References t38_non_ecm_buffer_state_t::at_initial_all_ones, t38_non_ecm_buffer_state_t::bit_stream, t38_non_ecm_buffer_state_t::flow_control_fill_octet, t38_non_ecm_buffer_state_t::image_data_mode, t38_non_ecm_buffer_state_t::min_row_bits, and t38_non_ecm_buffer_state_t::octet.

Referenced by t38_gateway_init().

void t38_non_ecm_buffer_inject	(	t38_non_ecm_buffer_state_t *	s,
		const uint8_t *	buf,
		int	len
	)

Inject data to T.38 rate adapting non-ECM buffer context.

Parameters:

	s	The buffer context.
	buf	The data buffer to be injected.
	len	The length of the data to be injected.

References t38_non_ecm_buffer_state_t::at_initial_all_ones, t38_non_ecm_buffer_state_t::bit_stream, t38_non_ecm_buffer_state_t::data, t38_non_ecm_buffer_state_t::flow_control_fill_octet, t38_non_ecm_buffer_state_t::image_data_mode, t38_non_ecm_buffer_state_t::in_octets, t38_non_ecm_buffer_state_t::in_ptr, t38_non_ecm_buffer_state_t::in_rows, t38_non_ecm_buffer_state_t::latest_eol_ptr, t38_non_ecm_buffer_state_t::min_row_bits, t38_non_ecm_buffer_state_t::min_row_bits_fill_octets, t38_non_ecm_buffer_state_t::row_bits, and T38_NON_ECM_TX_BUF_LEN.

void t38_non_ecm_buffer_push

(

t38_non_ecm_buffer_state_t *

s

)

Inform a T.38 rate adapting non-ECM buffer context that the incoming data has finished, and the contents of the buffer should be played out as quickly as possible.

Parameters:

s

The buffer context.

References t38_non_ecm_buffer_state_t::data_finished, t38_non_ecm_buffer_state_t::in_ptr, and t38_non_ecm_buffer_state_t::latest_eol_ptr.

void t38_non_ecm_buffer_report_input_status	(	t38_non_ecm_buffer_state_t *	s,
		logging_state_t *	logging
	)

Report the input status of a T.38 rate adapting non-ECM buffer context to the specified logging context.

Parameters:

	s	The buffer context.
	logging	The logging context.

References t38_non_ecm_buffer_state_t::in_octets, t38_non_ecm_buffer_state_t::in_rows, t38_non_ecm_buffer_state_t::min_row_bits_fill_octets, and span_log().

void t38_non_ecm_buffer_report_output_status	(	t38_non_ecm_buffer_state_t *	s,
		logging_state_t *	logging
	)

Report the output status of a T.38 rate adapting non-ECM buffer context to the specified logging context.

Parameters:

	s	The buffer context.
	logging	The logging context.

References t38_non_ecm_buffer_state_t::flow_control_fill_octets, t38_non_ecm_buffer_state_t::out_octets, t38_non_ecm_buffer_state_t::out_rows, and span_log().

void t38_non_ecm_buffer_set_mode	(	t38_non_ecm_buffer_state_t *	s,
		int	mode,
		int	min_row_bits
	)

Set the mode of a T.38 rate adapting non-ECM buffer context.

Parameters:

	s	The buffer context.
	mode	TRUE for image data mode, or FALSE for TCF mode.
	bits	The minimum number of bits per FAX image row.

References t38_non_ecm_buffer_state_t::image_data_mode, and t38_non_ecm_buffer_state_t::min_row_bits.