spandsp  0.0.6
private/t38_terminal.h
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1 /*
2  * SpanDSP - a series of DSP components for telephony
3  *
4  * private/t38_terminal.h - T.38 termination, less the packet exchange part
5  *
6  * Written by Steve Underwood <steveu@coppice.org>
7  *
8  * Copyright (C) 2005 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_T38_TERMINAL_H_)
29 #define _SPANDSP_PRIVATE_T38_TERMINAL_H_
30 
31 typedef struct
32 {
33  /*! \brief Internet Aware FAX mode bit mask. */
34  int iaf;
35  /*! \brief Required time between T.38 transmissions, in ms. */
37  /*! \brief Bit fields controlling the way data is packed into chunked for transmission. */
39 
40  /*! \brief Core T.38 IFP support */
42 
43  /*! \brief The current transmit step being timed */
45 
46  /*! \brief TRUE is there has been some T.38 data missed (i.e. lost packets) in the current
47  reception period. */
49 
50  /*! \brief The number of octets to send in each image packet (non-ECM or ECM) at the current
51  rate and the current specified packet interval. */
53 
54  struct
55  {
56  /*! \brief HDLC receive buffer */
57  uint8_t buf[T38_MAX_HDLC_LEN];
58  /*! \brief The length of the contents of the HDLC receive buffer */
59  int len;
60  } hdlc_rx;
61 
62  struct
63  {
64  /*! \brief HDLC transmit buffer */
65  uint8_t buf[T38_MAX_HDLC_LEN];
66  /*! \brief The length of the contents of the HDLC transmit buffer */
67  int len;
68  /*! \brief Current pointer within the contents of the HDLC transmit buffer */
69  int ptr;
70  /*! \brief The number of extra bits in a fully stuffed version of the
71  contents of the HDLC transmit buffer. This is needed to accurately
72  estimate the playout time for this frame, through an analogue modem. */
74  } hdlc_tx;
75 
76  /*! \brief Counter for trailing non-ECM bytes, used to flush out the far end's modem. */
78 
79  /*! \brief The next T.38 indicator queued for transmission. */
81  /*! \brief The current T.38 data type being transmitted. */
83 
84  /*! \brief TRUE if a carrier is present. Otherwise FALSE. */
86 
87  /*! \brief The current operating mode of the receiver. */
89  /*! \brief The current operating mode of the transmitter. */
91 
92  /*! \brief Current transmission bit rate. */
94  /*! \brief A "sample" count, used to time events. */
95  int32_t samples;
96  /*! \brief The value for samples at the next transmission point. */
97  int32_t next_tx_samples;
98  /*! \brief The current transmit timeout. */
99  //int32_t timeout_tx_samples;
100  /*! \brief The current receive timeout. */
103 
104 /*!
105  T.38 terminal state.
106 */
108 {
109  /*! \brief The T.30 back-end */
111 
112  /*! \brief The T.38 front-end */
114 
115  /*! \brief Error and flow logging control */
117 };
118 
119 #endif
120 /*- End of file ------------------------------------------------------------*/