#include <t4_t6_decode.h>

Public Attributes
t4_row_write_handler_t	row_write_handler
	The type of compression used between the FAX machines.
void *	row_write_user_data
	Opaque pointer passed to row_write_handler.
int	last_row_starts_at
	A pointer into the image buffer indicating where the last row begins.
int	consecutive_eols
	This variable is used to count the consecutive EOLS we have seen. If it reaches six, this is the end of the image. It is initially set to -1 for 1D and 2D decoding, as an indicator that we must wait for the first EOL, before decoding any image data.
int	a0
	The reference or starting changing element on the coding line. At the start of the coding line, a0 is set on an imaginary white changing element situated just before the first element on the line. During the coding of the coding line, the position of a0 is defined by the previous coding mode. (See T.4/4.2.1.3.2.).
int	b1
	The first changing element on the reference line to the right of a0 and of opposite colour to a0.
int	run_length
	The length of the in-progress run of black or white.
int	black_white
	2D horizontal mode control.
int	its_black
	TRUE if the current run is black.
int	a_cursor
	The current step into the current row run-lengths buffer.
int	b_cursor
	The current step into the reference row run-lengths buffer.
uint32_t	rx_bitstream
	Incoming bit buffer for decompression.
int	rx_bits
	The number of bits currently in rx_bitstream.
int	rx_skip_bits
	The number of bits to be skipped before trying to match the next code word.
int	curr_bad_row_run
	Decoded pixel buffer.
int	longest_bad_row_run
	The longest run of consecutive bad rows seen in the current page.
int	bad_rows
	The total number of bad rows in the current page.

Detailed Description

T.4 1D, T4 2D and T6 decompressor state.

Member Data Documentation

◆ a0

int t4_t6_decode_state_s::a0

The reference or starting changing element on the coding line. At the start of the coding line, a0 is set on an imaginary white changing element situated just before the first element on the line. During the coding of the coding line, the position of a0 is defined by the previous coding mode. (See T.4/4.2.1.3.2.).

Referenced by t4_rx_start_page().

◆ a_cursor

int t4_t6_decode_state_s::a_cursor

The current step into the current row run-lengths buffer.

Referenced by t4_rx_start_page().

◆ b1

int t4_t6_decode_state_s::b1

The first changing element on the reference line to the right of a0 and of opposite colour to a0.

Referenced by t4_rx_start_page().

◆ b_cursor

int t4_t6_decode_state_s::b_cursor

The current step into the reference row run-lengths buffer.

Referenced by t4_rx_start_page().

◆ bad_rows

int t4_t6_decode_state_s::bad_rows

The total number of bad rows in the current page.

Referenced by t4_rx_get_transfer_statistics(), t4_rx_start_page(), and t4_tx_get_transfer_statistics().

◆ black_white

int t4_t6_decode_state_s::black_white

2D horizontal mode control.

Referenced by t4_rx_start_page().

◆ consecutive_eols

int t4_t6_decode_state_s::consecutive_eols

This variable is used to count the consecutive EOLS we have seen. If it reaches six, this is the end of the image. It is initially set to -1 for 1D and 2D decoding, as an indicator that we must wait for the first EOL, before decoding any image data.

Referenced by t4_rx_end_page(), and t4_rx_start_page().