t4_rx.c File Reference

#include <stdlib.h>
#include <inttypes.h>
#include <limits.h>
#include <stdio.h>
#include <fcntl.h>
#include <unistd.h>
#include <time.h>
#include <memory.h>
#include <string.h>
#include <tgmath.h>
#include <math.h>
#include "floating_fudge.h"
#include <tiffio.h>
#include "spandsp/telephony.h"
#include "spandsp/logging.h"
#include "spandsp/bit_operations.h"
#include "spandsp/async.h"
#include "spandsp/timezone.h"
#include "spandsp/t4_rx.h"
#include "spandsp/t4_tx.h"
#include "spandsp/image_translate.h"
#include "spandsp/t81_t82_arith_coding.h"
#include "spandsp/t85.h"
#include "spandsp/t42.h"
#include "spandsp/t4_t6_decode.h"
#include "spandsp/t4_t6_encode.h"
#include "spandsp/version.h"
#include "spandsp/private/logging.h"
#include "spandsp/private/t81_t82_arith_coding.h"
#include "spandsp/private/t85.h"
#include "spandsp/private/t42.h"
#include "spandsp/private/t4_t6_decode.h"
#include "spandsp/private/t4_t6_encode.h"
#include "spandsp/private/image_translate.h"
#include "spandsp/private/t4_rx.h"
#include "spandsp/private/t4_tx.h"

Defines
#define	CM_PER_INCH   2.54f
Functions
const char *	t4_encoding_to_str (int encoding)
	Get the short text name of an encoding format.
int	t4_rx_put_bit (t4_rx_state_t *s, int bit)
	Put a bit of the current document page.
int	t4_rx_put (t4_rx_state_t *s, const uint8_t buf[], size_t len)
	Put a byte of the current document page.
void	t4_rx_set_y_resolution (t4_rx_state_t *s, int resolution)
	Set the row-to-row (y) resolution to expect for a received image.
void	t4_rx_set_x_resolution (t4_rx_state_t *s, int resolution)
	Set the column-to-column (x) resolution to expect for a received image.
void	t4_rx_set_dcs (t4_rx_state_t *s, const char *dcs)
	Set the DCS information of the fax, for inclusion in the file.
void	t4_rx_set_sub_address (t4_rx_state_t *s, const char *sub_address)
	Set the sub-address of the fax, for inclusion in the file.
void	t4_rx_set_far_ident (t4_rx_state_t *s, const char *ident)
	Set the identity of the remote machine, for inclusion in the file.
void	t4_rx_set_vendor (t4_rx_state_t *s, const char *vendor)
	Set the vendor of the remote machine, for inclusion in the file.
void	t4_rx_set_model (t4_rx_state_t *s, const char *model)
	Set the model of the remote machine, for inclusion in the file.
int	t4_rx_set_rx_encoding (t4_rx_state_t *s, int encoding)
	Set the encoding for the received data.
void	t4_rx_set_image_width (t4_rx_state_t *s, int width)
	Set the expected width of the received image, in pixel columns.
int	t4_rx_set_row_write_handler (t4_rx_state_t *s, t4_row_write_handler_t handler, void *user_data)
	Set the row write handler for a T.4 receive context.
void	t4_rx_get_transfer_statistics (t4_rx_state_t *s, t4_stats_t *t)
	Get the current transfer statistics.
int	t4_rx_start_page (t4_rx_state_t *s)
	Prepare to receive the next page of the current document.
int	t4_rx_end_page (t4_rx_state_t *s)
	Complete the reception of a page.
t4_rx_state_t *	t4_rx_init (t4_rx_state_t *s, const char *file, int output_encoding)
	Prepare for reception of a document.
int	t4_rx_release (t4_rx_state_t *s)
	End reception of a document. Tidy up and close the file. This should be used to end T.4 reception started with t4_rx_init.
int	t4_rx_free (t4_rx_state_t *s)
	End reception of a document. Tidy up, close the file and free the context. This should be used to end T.4 reception started with t4_rx_init.

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Detailed Description

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Define Documentation

#define CM_PER_INCH   2.54f

The number of centimetres in one inch

---

Function Documentation

const char* t4_encoding_to_str

(

int

encoding

)

Get the short text name of an encoding format.

Get the short text name of an encoding format.

Parameters:

encoding

The encoding type.

Returns:

A pointer to the string.

References T4_COMPRESSION_ITU_SYCC_T42, T4_COMPRESSION_ITU_T42, T4_COMPRESSION_ITU_T43, T4_COMPRESSION_ITU_T45, T4_COMPRESSION_ITU_T4_1D, T4_COMPRESSION_ITU_T4_2D, T4_COMPRESSION_ITU_T6, T4_COMPRESSION_ITU_T85, T4_COMPRESSION_ITU_T85_L0, and T4_COMPRESSION_NONE.

Referenced by t4_rx_start_page(), and t4_tx_start_page().

int t4_rx_end_page

(

t4_rx_state_t *

s

)

Complete the reception of a page.

Parameters:

s

The T.4 receive context.

Returns:

0 for success, otherwise -1.

References T4_COMPRESSION_ITU_T42, T4_COMPRESSION_ITU_T43, T4_COMPRESSION_ITU_T4_1D, T4_COMPRESSION_ITU_T4_2D, T4_COMPRESSION_ITU_T6, T4_COMPRESSION_ITU_T85, T4_COMPRESSION_ITU_T85_L0, t4_t6_decode_get_image_length(), t4_t6_decode_put(), t85_decode_get_image_length(), and t85_decode_put().

int t4_rx_free

(

t4_rx_state_t *

s

)

End reception of a document. Tidy up, close the file and free the context. This should be used to end T.4 reception started with t4_rx_init.

Parameters:

s

The T.4 receive context.

Returns:

0 for success, otherwise -1.

References t4_rx_release().

void t4_rx_get_transfer_statistics	(	t4_rx_state_t *	s,
		t4_stats_t *	t
	)

Get the current transfer statistics.

Get the current image transfer statistics.

Parameters:

	s	The T.4 context.
	t	A pointer to a statistics structure.

References T4_COMPRESSION_ITU_T42, T4_COMPRESSION_ITU_T43, T4_COMPRESSION_ITU_T4_1D, T4_COMPRESSION_ITU_T4_2D, T4_COMPRESSION_ITU_T6, T4_COMPRESSION_ITU_T85, T4_COMPRESSION_ITU_T85_L0, t4_t6_decode_get_compressed_image_size(), t4_t6_decode_get_image_length(), t4_t6_decode_get_image_width(), t85_decode_get_compressed_image_size(), t85_decode_get_image_length(), and t85_decode_get_image_width().

Referenced by t30_get_transfer_statistics().

t4_rx_state_t* t4_rx_init	(	t4_rx_state_t *	s,
		const char *	file,
		int	output_encoding
	)

Prepare for reception of a document.

Parameters:

	s	The T.4 context.
	file	The name of the file to be received.
	output_encoding	The output encoding.

Returns:

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

References span_log().

int t4_rx_put	(	t4_rx_state_t *	s,
		const uint8_t	buf[],
		size_t	len
	)

Put a byte of the current document page.

Parameters:

	s	The T.4 context.
	buf	The buffer containing the chunk.
	len	The length of the chunk.

Returns:

TRUE when the byte ends the document page, otherwise FALSE.

References T4_COMPRESSION_ITU_T42, T4_COMPRESSION_ITU_T43, T4_COMPRESSION_ITU_T4_1D, T4_COMPRESSION_ITU_T4_2D, T4_COMPRESSION_ITU_T6, T4_COMPRESSION_ITU_T85, T4_COMPRESSION_ITU_T85_L0, T4_DECODE_OK, t4_t6_decode_put(), and t85_decode_put().

Referenced by t30_non_ecm_put().

int t4_rx_put_bit	(	t4_rx_state_t *	s,
		int	bit
	)

Put a bit of the current document page.

Parameters:

	s	The T.4 context.
	bit	The data bit.

Returns:

TRUE when the bit ends the document page, otherwise FALSE.

References t4_t6_decode_put_bit().

int t4_rx_release

(

t4_rx_state_t *

s

)

End reception of a document. Tidy up and close the file. This should be used to end T.4 reception started with t4_rx_init.

Parameters:

s

The T.4 receive context.

Returns:

0 for success, otherwise -1.

References T4_COMPRESSION_ITU_T42, T4_COMPRESSION_ITU_T43, T4_COMPRESSION_ITU_T4_1D, T4_COMPRESSION_ITU_T4_2D, T4_COMPRESSION_ITU_T6, T4_COMPRESSION_ITU_T85, and T4_COMPRESSION_ITU_T85_L0.

Referenced by t4_rx_free().

void t4_rx_set_dcs	(	t4_rx_state_t *	s,
		const char *	dcs
	)

Set the DCS information of the fax, for inclusion in the file.

Parameters:

	s	The T.4 context.
	dcs	The DCS information, formatted as an ASCII string.

void t4_rx_set_far_ident	(	t4_rx_state_t *	s,
		const char *	ident
	)

Set the identity of the remote machine, for inclusion in the file.

Parameters:

	s	The T.4 context.
	ident	The identity string.

void t4_rx_set_image_width	(	t4_rx_state_t *	s,
		int	width
	)

Set the expected width of the received image, in pixel columns.

Parameters:

	s	The T.4 context.
	width	The number of pixels across the image.

void t4_rx_set_model	(	t4_rx_state_t *	s,
		const char *	model
	)

Set the model of the remote machine, for inclusion in the file.

Parameters:

	s	The T.4 context.
	model	The model string, or NULL.

int t4_rx_set_row_write_handler	(	t4_rx_state_t *	s,
		t4_row_write_handler_t	handler,
		void *	user_data
	)

Set the row write handler for a T.4 receive context.

Parameters:

	s	The T.4 receive context.
	handler	A pointer to the handler routine.
	user_data	An opaque pointer passed to the handler routine.

Returns:

0 for success, otherwise -1.

References T4_COMPRESSION_ITU_T42, T4_COMPRESSION_ITU_T43, T4_COMPRESSION_ITU_T4_1D, T4_COMPRESSION_ITU_T4_2D, T4_COMPRESSION_ITU_T6, T4_COMPRESSION_ITU_T85, T4_COMPRESSION_ITU_T85_L0, t4_t6_decode_set_row_write_handler(), and t85_decode_set_row_write_handler().

int t4_rx_set_rx_encoding	(	t4_rx_state_t *	s,
		int	encoding
	)

Set the encoding for the received data.

Parameters:

	s	The T.4 context.
	encoding	The encoding.

Returns:

0 for success, otherwise -1.

References T4_COMPRESSION_ITU_T42, T4_COMPRESSION_ITU_T43, T4_COMPRESSION_ITU_T4_1D, T4_COMPRESSION_ITU_T4_2D, T4_COMPRESSION_ITU_T6, T4_COMPRESSION_ITU_T85, T4_COMPRESSION_ITU_T85_L0, t4_t6_decode_init(), t4_t6_decode_set_encoding(), t85_decode_init(), and t85_decode_set_image_size_constraints().

void t4_rx_set_sub_address	(	t4_rx_state_t *	s,
		const char *	sub_address
	)

Set the sub-address of the fax, for inclusion in the file.

Parameters:

	s	The T.4 context.
	sub_address	The sub-address string.

void t4_rx_set_vendor	(	t4_rx_state_t *	s,
		const char *	vendor
	)

Set the vendor of the remote machine, for inclusion in the file.

Parameters:

	s	The T.4 context.
	vendor	The vendor string, or NULL.

void t4_rx_set_x_resolution	(	t4_rx_state_t *	s,
		int	resolution
	)

Set the column-to-column (x) resolution to expect for a received image.

Parameters:

	s	The T.4 context.
	resolution	The resolution, in pixels per metre.

void t4_rx_set_y_resolution	(	t4_rx_state_t *	s,
		int	resolution
	)

Set the row-to-row (y) resolution to expect for a received image.

Parameters:

	s	The T.4 context.
	resolution	The resolution, in pixels per metre.

int t4_rx_start_page

(

t4_rx_state_t *

s

)

Prepare to receive the next page of the current document.

Parameters:

s

The T.4 context.

Returns:

zero for success, -1 for failure.

References span_log(), T4_COMPRESSION_ITU_T42, T4_COMPRESSION_ITU_T43, T4_COMPRESSION_ITU_T4_1D, T4_COMPRESSION_ITU_T4_2D, T4_COMPRESSION_ITU_T6, T4_COMPRESSION_ITU_T85, T4_COMPRESSION_ITU_T85_L0, and t4_encoding_to_str().