spandsp  0.0.6
private/t30.h
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1 /*
2  * SpanDSP - a series of DSP components for telephony
3  *
4  * private/t30.h - definitions for T.30 fax processing
5  *
6  * Written by Steve Underwood <steveu@coppice.org>
7  *
8  * Copyright (C) 2003 Steve Underwood
9  *
10  * All rights reserved.
11  *
12  * This program is free software; you can redistribute it and/or modify
13  * it under the terms of the GNU Lesser General Public License version 2.1,
14  * as published by the Free Software Foundation.
15  *
16  * This program is distributed in the hope that it will be useful,
17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19  * GNU Lesser General Public License for more details.
20  *
21  * You should have received a copy of the GNU Lesser General Public
22  * License along with this program; if not, write to the Free Software
23  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
24  */
25 
26 /*! \file */
27 
28 #if !defined(_SPANDSP_PRIVATE_T30_H_)
29 #define _SPANDSP_PRIVATE_T30_H_
30 
31 /*!
32  T.30 FAX channel descriptor. This defines the state of a single working
33  instance of a T.30 FAX channel.
34 */
36 {
37  /*! \brief T.4 context for reading or writing image data. */
38  union
39  {
40  t4_state_t rx;
41  t4_state_t tx;
42  } t4;
43  /*! \brief The type of FAX operation currently in progress */
45 
46  /*! \brief TRUE if behaving as the calling party */
48 
49  /*! \brief Internet aware FAX mode bit mask. */
50  int iaf;
51  /*! \brief A bit mask of the currently supported modem types. */
53  /*! \brief A bit mask of the currently supported image compression modes. */
55  /*! \brief A bit mask of the currently supported image resolutions. */
57  /*! \brief A bit mask of the currently supported image sizes. */
59  /*! \brief A bit mask of the currently supported T.30 special features. */
61  /*! \brief TRUE is ECM mode handling is enabled. */
63  /*! \brief TRUE if we are capable of retransmitting pages */
65 
66  /*! \brief The received DCS, formatted as an ASCII string, for inclusion
67  in the TIFF file. */
69  /*! \brief The text which will be used in FAX page header. No text results
70  in no header line. */
72  /*! \brief TRUE for FAX page headers to overlay (i.e. replace) the beginning of the
73  page image. FALSE for FAX page headers to add to the overall length of
74  the page. */
76  /*! \brief TRUE if remote T.30 procedural interrupts are allowed. */
78 
79  /*! \brief The information fields received. */
81  /*! \brief The information fields to be transmitted. */
83  /*! \brief The country of origin of the remote machine, if known, else NULL. */
84  const char *country;
85  /*! \brief The vendor of the remote machine, if known, else NULL. */
86  const char *vendor;
87  /*! \brief The model of the remote machine, if known, else NULL. */
88  const char *model;
89 
90  /*! \brief A pointer to a callback routine to be called when phase B events
91  occur. */
93  /*! \brief An opaque pointer supplied in event B callbacks. */
95  /*! \brief A pointer to a callback routine to be called when phase D events
96  occur. */
98  /*! \brief An opaque pointer supplied in event D callbacks. */
100  /*! \brief A pointer to a callback routine to be called when phase E events
101  occur. */
103  /*! \brief An opaque pointer supplied in event E callbacks. */
105  /*! \brief A pointer to a callback routine to be called when frames are
106  exchanged. */
108  /*! \brief An opaque pointer supplied in real time frame callbacks. */
110 
111  /*! \brief A pointer to a callback routine to be called when document events
112  (e.g. end of transmitted document) occur. */
114  /*! \brief An opaque pointer supplied in document callbacks. */
116 
117  /*! \brief The handler for changes to the receive mode */
119  /*! \brief An opaque pointer passed to the handler for changes to the receive mode */
121  /*! \brief The handler for changes to the transmit mode */
123  /*! \brief An opaque pointer passed to the handler for changes to the transmit mode */
125 
126  /*! \brief The transmitted HDLC frame handler. */
128  /*! \brief An opaque pointer passed to the transmitted HDLC frame handler. */
130 
131  /*! \brief The DIS code for the minimum scan row time we require. This is usually 0ms,
132  but if we are trying to simulate another type of FAX machine, we may need a non-zero
133  value here. */
135 
136  /*! \brief The current T.30 phase. */
137  int phase;
138  /*! \brief The T.30 phase to change to when the current phase ends. */
140  /*! \brief The current state of the T.30 state machine. */
141  int state;
142  /*! \brief The step in sending a sequence of HDLC frames. */
143  int step;
144 
145  /*! \brief The preparation buffer for the DCS message to be transmitted. */
147  /*! \brief The length of the DCS message to be transmitted. */
148  int dcs_len;
149  /*! \brief The preparation buffer for DIS or DTC message to be transmitted. */
151  /*! \brief The length of the DIS or DTC message to be transmitted. */
153  /*! \brief The last DIS or DTC message received form the far end. */
155  /*! \brief The length of the last DIS or DTC message received form the far end. */
157  /*! \brief TRUE if a valid DIS has been received from the far end. */
159 
160  /*! \brief TRUE if the short training sequence should be used. */
162 
163  /*! \brief A count of the number of bits in the trainability test. This counts down to zero when
164  sending TCF, and counts up when receiving it. */
166  /*! \brief The current count of consecutive received zero bits, during the trainability test. */
168  /*! \brief The maximum consecutive received zero bits seen to date, during the trainability test. */
170 
171  /*! \brief The current fallback step for the fast message transfer modem. */
173  /*! \brief The subset of supported modems allowed at the current time, allowing for negotiation. */
175  /*! \brief TRUE if a carrier is present. Otherwise FALSE. */
177  /*! \brief TRUE if a modem has trained correctly. */
179  /*! \brief TRUE if a valid HDLC frame has been received in the current reception period. */
181 
182  /*! \brief Current reception mode. */
184  /*! \brief Current transmission mode. */
186 
187  /*! \brief T0 is the answer timeout when calling another FAX machine.
188  Placing calls is handled outside the FAX processing, but this timeout keeps
189  running until V.21 modulation is sent or received.
190  T1 is the remote terminal identification timeout (in audio samples). */
192  /*! \brief T2, T2A and T2B are the HDLC command timeouts.
193  T4, T4A and T4B are the HDLC response timeouts (in audio samples). */
195  /*! \brief A value specifying which of the possible timers is currently running in timer_t2_t4 */
197  /*! \brief Procedural interrupt timeout (in audio samples). */
198  int timer_t3;
199  /*! \brief This is only used in error correcting mode. */
200  int timer_t5;
201  /*! \brief This is only used in full duplex (e.g. ISDN) modes. */
202  int timer_t6;
203  /*! \brief This is only used in full duplex (e.g. ISDN) modes. */
204  int timer_t7;
205  /*! \brief This is only used in full duplex (e.g. ISDN) modes. */
206  int timer_t8;
207 
208  /*! \brief TRUE once the far end FAX entity has been detected. */
210 
211  /*! \brief TRUE if a local T.30 interrupt is pending. */
213  /*! \brief The image coding being used on the line. */
215  /*! \brief The image coding being used for output files. */
217  /*! \brief The current DCS message minimum scan time code. */
219  /*! \brief The X direction resolution of the current image, in pixels per metre. */
221  /*! \brief The Y direction resolution of the current image, in pixels per metre. */
223  /*! \brief The width of the current image, in pixels. */
225  /*! \brief Current number of retries of the action in progress. */
226  int retries;
227  /*! \brief TRUE if error correcting mode is used. */
229  /*! \brief The number of HDLC frame retries, if error correcting mode is used. */
231  /*! \brief The current count of consecutive T30_PPR messages. */
233  /*! \brief The current count of consecutive T30_RNR messages. */
235  /*! \brief The number of octets to be used per ECM frame. */
237  /*! \brief The ECM partial page buffer. */
238  uint8_t ecm_data[256][260];
239  /*! \brief The lengths of the frames in the ECM partial page buffer. */
240  int16_t ecm_len[256];
241  /*! \brief A bit map of the OK ECM frames, constructed as a PPR frame. */
242  uint8_t ecm_frame_map[3 + 32];
243 
244  /*! \brief The current page number for receiving, in ECM or non-ECM mode. This is reset at the start of a call. */
246  /*! \brief The current page number for sending, in ECM or non-ECM mode. This is reset at the start of a call. */
248  /*! \brief The current block number, in ECM mode */
250  /*! \brief The number of frames in the current block number, in ECM mode */
252  /*! \brief The number of frames sent in the current burst of image transmission, in ECM mode */
254  /*! \brief The current ECM frame, during ECM transmission. */
256  /*! \brief TRUE if we are at the end of an ECM page to se sent - i.e. there are no more
257  partial pages still to come. */
259 
260  /*! \brief The transmission step queued to follow the one in progress. */
262  /*! \brief The FCF for the next receive step. */
263  uint8_t next_rx_step;
264  /*! \brief Image file name for image reception. */
265  char rx_file[256];
266  /*! \brief The last page we are prepared accept for a received image file. -1 means no restriction. */
268  /*! \brief Image file name to be sent. */
269  char tx_file[256];
270  /*! \brief The first page to be sent from the image file. -1 means no restriction. */
272  /*! \brief The last page to be sent from the image file. -1 means no restriction. */
274  /*! \brief The current completion status. */
276 
277  /*! \brief The number of RTP events */
279  /*! \brief The number of RTN events */
281 
282  /*! \brief the FCF2 field of the last PPS message we received. */
283  uint8_t last_pps_fcf2;
284  /*! \brief TRUE if all frames of the current received ECM block are now OK */
286  /*! \brief A count of successfully received ECM frames, to assess progress as a basis for
287  deciding whether to continue error correction when PPRs keep repeating. */
289 
290  /*! \brief Error and flow logging control */
292 };
293 
294 #endif
295 /*- End of file ------------------------------------------------------------*/
int far_dis_dtc_len
The length of the last DIS or DTC message received form the far end.
Definition: private/t30.h:156
int timer_t2_t4
T2, T2A and T2B are the HDLC command timeouts. T4, T4A and T4B are the HDLC response timeouts (in aud...
Definition: private/t30.h:194
uint8_t next_rx_step
The FCF for the next receive step.
Definition: private/t30.h:263
uint8_t dcs_frame[T30_MAX_DIS_DTC_DCS_LEN]
The preparation buffer for the DCS message to be transmitted.
Definition: private/t30.h:146
int remote_interrupts_allowed
TRUE if remote T.30 procedural interrupts are allowed.
Definition: private/t30.h:77
int supported_compressions
A bit mask of the currently supported image compression modes.
Definition: private/t30.h:54
t30_document_handler_t * document_handler
A pointer to a callback routine to be called when document events (e.g. end of transmitted document) ...
Definition: private/t30.h:113
const char * model
The model of the remote machine, if known, else NULL.
Definition: private/t30.h:88
char tx_file[256]
Image file name to be sent.
Definition: private/t30.h:269
int output_encoding
The image coding being used for output files.
Definition: private/t30.h:216
void * send_hdlc_user_data
An opaque pointer passed to the transmitted HDLC frame handler.
Definition: private/t30.h:129
int timer_t0_t1
T0 is the answer timeout when calling another FAX machine. Placing calls is handled outside the FAX p...
Definition: private/t30.h:191
int current_fallback
The current fallback step for the fast message transfer modem.
Definition: private/t30.h:172
char header_info[T30_MAX_PAGE_HEADER_INFO+1]
The text which will be used in FAX page header. No text results in no header line.
Definition: private/t30.h:71
int calling_party
TRUE if behaving as the calling party.
Definition: private/t30.h:47
int rx_stop_page
The last page we are prepared accept for a received image file. -1 means no restriction.
Definition: private/t30.h:267
int tx_page_number
The current page number for sending, in ECM or non-ECM mode. This is reset at the start of a call...
Definition: private/t30.h:247
Definition: private/t30.h:35
uint8_t min_scan_time_code
The current DCS message minimum scan time code.
Definition: private/t30.h:218
uint8_t ecm_data[256][260]
The ECM partial page buffer.
Definition: private/t30.h:238
void * real_time_frame_user_data
An opaque pointer supplied in real time frame callbacks.
Definition: private/t30.h:109
int ecm_frames
The number of frames in the current block number, in ECM mode.
Definition: private/t30.h:251
int next_tx_step
The transmission step queued to follow the one in progress.
Definition: private/t30.h:261
void( t30_phase_e_handler_t)(t30_state_t *s, void *user_data, int completion_code)
T.30 phase E callback handler.
Definition: t30.h:180
int16_t ecm_len[256]
The lengths of the frames in the ECM partial page buffer.
Definition: private/t30.h:240
t4_image_width_t image_width
The width of the current image, in pixels.
Definition: private/t30.h:224
int tx_stop_page
The last page to be sent from the image file. -1 means no restriction.
Definition: private/t30.h:273
int header_overlays_image
TRUE for FAX page headers to overlay (i.e. replace) the beginning of the page image. FALSE for FAX page headers to add to the overall length of the page.
Definition: private/t30.h:75
int supported_resolutions
A bit mask of the currently supported image resolutions.
Definition: private/t30.h:56
int rtp_events
The number of RTP events.
Definition: private/t30.h:278
void( t30_send_hdlc_handler_t)(void *user_data, const uint8_t msg[], int len)
T.30 send HDLC handler.
Definition: t30.h:224
uint8_t far_dis_dtc_frame[T30_MAX_DIS_DTC_DCS_LEN]
The last DIS or DTC message received form the far end.
Definition: private/t30.h:154
int timer_t7
This is only used in full duplex (e.g. ISDN) modes.
Definition: private/t30.h:204
t30_phase_e_handler_t * phase_e_handler
A pointer to a callback routine to be called when phase E events occur.
Definition: private/t30.h:102
int tcf_test_bits
A count of the number of bits in the trainability test. This counts down to zero when sending TCF...
Definition: private/t30.h:165
int ecm_block
The current block number, in ECM mode.
Definition: private/t30.h:249
int line_encoding
The image coding being used on the line.
Definition: private/t30.h:214
int short_train
TRUE if the short training sequence should be used.
Definition: private/t30.h:161
int timer_t6
This is only used in full duplex (e.g. ISDN) modes.
Definition: private/t30.h:202
int local_dis_dtc_len
The length of the DIS or DTC message to be transmitted.
Definition: private/t30.h:152
char rx_dcs_string[T30_MAX_DIS_DTC_DCS_LEN *3+1]
The received DCS, formatted as an ASCII string, for inclusion in the TIFF file.
Definition: private/t30.h:68
int rx_ecm_block_ok
TRUE if all frames of the current received ECM block are now OK.
Definition: private/t30.h:285
int local_interrupt_pending
TRUE if a local T.30 interrupt is pending.
Definition: private/t30.h:212
t30_set_handler_t * set_tx_type_handler
The handler for changes to the transmit mode.
Definition: private/t30.h:122
int y_resolution
The Y direction resolution of the current image, in pixels per metre.
Definition: private/t30.h:222
int rx_trained
TRUE if a modem has trained correctly.
Definition: private/t30.h:178
#define T30_MAX_DIS_DTC_DCS_LEN
Definition: t30.h:142
t30_real_time_frame_handler_t * real_time_frame_handler
A pointer to a callback routine to be called when frames are exchanged.
Definition: private/t30.h:107
uint8_t local_dis_dtc_frame[T30_MAX_DIS_DTC_DCS_LEN]
The preparation buffer for DIS or DTC message to be transmitted.
Definition: private/t30.h:150
int rtn_events
The number of RTN events.
Definition: private/t30.h:280
t30_exchanged_info_t rx_info
The information fields received.
Definition: private/t30.h:80
int current_status
The current completion status.
Definition: private/t30.h:275
int( t30_phase_b_handler_t)(t30_state_t *s, void *user_data, int result)
T.30 phase B callback handler.
Definition: t30.h:161
logging_state_t logging
Error and flow logging control.
Definition: private/t30.h:291
int current_permitted_modems
The subset of supported modems allowed at the current time, allowing for negotiation.
Definition: private/t30.h:174
int current_rx_type
Current reception mode.
Definition: private/t30.h:183
char rx_file[256]
Image file name for image reception.
Definition: private/t30.h:265
void( t30_set_handler_t)(void *user_data, int type, int bit_rate, int short_train, int use_hdlc)
T.30 set a receive or transmit type handler.
Definition: t30.h:215
t30_phase_d_handler_t * phase_d_handler
A pointer to a callback routine to be called when phase D events occur.
Definition: private/t30.h:97
int octets_per_ecm_frame
The number of octets to be used per ECM frame.
Definition: private/t30.h:236
void * set_rx_type_user_data
An opaque pointer passed to the handler for changes to the receive mode.
Definition: private/t30.h:120
int error_correcting_mode_retries
The number of HDLC frame retries, if error correcting mode is used.
Definition: private/t30.h:230
int operation_in_progress
The type of FAX operation currently in progress.
Definition: private/t30.h:44
int supported_modems
A bit mask of the currently supported modem types.
Definition: private/t30.h:52
int current_tx_type
Current transmission mode.
Definition: private/t30.h:185
int step
The step in sending a sequence of HDLC frames.
Definition: private/t30.h:143
int ppr_count
The current count of consecutive T30_PPR messages.
Definition: private/t30.h:232
void( t30_real_time_frame_handler_t)(t30_state_t *s, void *user_data, int direction, const uint8_t msg[], int len)
T.30 real time frame handler.
Definition: t30.h:191
int phase
The current T.30 phase.
Definition: private/t30.h:137
void * phase_e_user_data
An opaque pointer supplied in event E callbacks.
Definition: private/t30.h:104
#define T30_MAX_PAGE_HEADER_INFO
Definition: t30.h:146
int rx_signal_present
TRUE if a carrier is present. Otherwise FALSE.
Definition: private/t30.h:176
void * phase_b_user_data
An opaque pointer supplied in event B callbacks.
Definition: private/t30.h:94
int far_end_detected
TRUE once the far end FAX entity has been detected.
Definition: private/t30.h:209
t4_image_width_t
Definition: t4_rx.h:110
int retries
Current number of retries of the action in progress.
Definition: private/t30.h:226
int ecm_allowed
TRUE is ECM mode handling is enabled.
Definition: private/t30.h:62
void * phase_d_user_data
An opaque pointer supplied in event D callbacks.
Definition: private/t30.h:99
int x_resolution
The X direction resolution of the current image, in pixels per metre.
Definition: private/t30.h:220
int next_phase
The T.30 phase to change to when the current phase ends.
Definition: private/t30.h:139
void * set_tx_type_user_data
An opaque pointer passed to the handler for changes to the transmit mode.
Definition: private/t30.h:124
int ecm_at_page_end
TRUE if we are at the end of an ECM page to se sent - i.e. there are no more partial pages still to c...
Definition: private/t30.h:258
Definition: private/logging.h:33
const char * country
The country of origin of the remote machine, if known, else NULL.
Definition: private/t30.h:84
int dcs_len
The length of the DCS message to be transmitted.
Definition: private/t30.h:148
int rx_page_number
The current page number for receiving, in ECM or non-ECM mode. This is reset at the start of a call...
Definition: private/t30.h:245
int timer_t5
This is only used in error correcting mode.
Definition: private/t30.h:200
uint8_t local_min_scan_time_code
The DIS code for the minimum scan row time we require. This is usually 0ms, but if we are trying to s...
Definition: private/t30.h:134
uint8_t ecm_frame_map[3+32]
A bit map of the OK ECM frames, constructed as a PPR frame.
Definition: private/t30.h:242
t30_send_hdlc_handler_t * send_hdlc_handler
The transmitted HDLC frame handler.
Definition: private/t30.h:127
int timer_t3
Procedural interrupt timeout (in audio samples).
Definition: private/t30.h:198
uint8_t last_pps_fcf2
the FCF2 field of the last PPS message we received.
Definition: private/t30.h:283
int( t30_phase_d_handler_t)(t30_state_t *s, void *user_data, int result)
T.30 phase D callback handler.
Definition: t30.h:171
int timer_t2_t4_is
A value specifying which of the possible timers is currently running in timer_t2_t4.
Definition: private/t30.h:196
t30_phase_b_handler_t * phase_b_handler
A pointer to a callback routine to be called when phase B events occur.
Definition: private/t30.h:92
t30_set_handler_t * set_rx_type_handler
The handler for changes to the receive mode.
Definition: private/t30.h:118
int error_correcting_mode
TRUE if error correcting mode is used.
Definition: private/t30.h:228
int supported_t30_features
A bit mask of the currently supported T.30 special features.
Definition: private/t30.h:60
int ecm_current_tx_frame
The current ECM frame, during ECM transmission.
Definition: private/t30.h:255
int ecm_frames_this_tx_burst
The number of frames sent in the current burst of image transmission, in ECM mode.
Definition: private/t30.h:253
union t30_state_s::@52 t4
T.4 context for reading or writing image data.
int iaf
Internet aware FAX mode bit mask.
Definition: private/t30.h:50
const char * vendor
The vendor of the remote machine, if known, else NULL.
Definition: private/t30.h:86
int tcf_most_zeros
The maximum consecutive received zero bits seen to date, during the trainability test.
Definition: private/t30.h:169
int ecm_progress
A count of successfully received ECM frames, to assess progress as a basis for deciding whether to co...
Definition: private/t30.h:288
int( t30_document_handler_t)(t30_state_t *s, void *user_data, int status)
T.30 document handler.
Definition: t30.h:204
int rx_frame_received
TRUE if a valid HDLC frame has been received in the current reception period.
Definition: private/t30.h:180
int supported_image_sizes
A bit mask of the currently supported image sizes.
Definition: private/t30.h:58
int dis_received
TRUE if a valid DIS has been received from the far end.
Definition: private/t30.h:158
Definition: private/t4_tx.h:33
void * document_user_data
An opaque pointer supplied in document callbacks.
Definition: private/t30.h:115
Definition: t30.h:473
int receiver_not_ready_count
The current count of consecutive T30_RNR messages.
Definition: private/t30.h:234
int retransmit_capable
TRUE if we are capable of retransmitting pages.
Definition: private/t30.h:64
t30_exchanged_info_t tx_info
The information fields to be transmitted.
Definition: private/t30.h:82
int tx_start_page
The first page to be sent from the image file. -1 means no restriction.
Definition: private/t30.h:271
int timer_t8
This is only used in full duplex (e.g. ISDN) modes.
Definition: private/t30.h:206
int state
The current state of the T.30 state machine.
Definition: private/t30.h:141
int tcf_current_zeros
The current count of consecutive received zero bits, during the trainability test.
Definition: private/t30.h:167