spandsp  0.0.6
private/t4_t6_encode.h
1 /*
2  * SpanDSP - a series of DSP components for telephony
3  *
4  * private/t4_t6_encode.h - definitions for T.4/T.6 fax compression
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 #if !defined(_SPANDSP_PRIVATE_T4_T6_ENCODE_H_)
27 #define _SPANDSP_PRIVATE_T4_T6_ENCODE_H_
28 
29 /*!
30  T.4 1D, T4 2D and T6 compressor state.
31 */
33 {
34  /*! \brief The minimum number of encoded bits per row. This is a timing thing
35  for hardware FAX machines. */
37  /*! \brief The current maximum contiguous rows that may be 2D encoded. */
39 
40  /*! \brief Number of rows left that can be 2D encoded, before a 1D encoded row
41  must be used. */
43 
44  /*! \brief The number of runs currently in the reference row. */
45  int ref_steps;
46 
47  /*! \brief Pointer to the byte containing the next image bit to transmit. */
48  int bit_pos;
49  /*! \brief Pointer to the bit within the byte containing the next image bit to transmit. */
50  int bit_ptr;
51 
52  /*! \brief Callback function to read a row of pixels from the image source. */
53  t4_row_read_handler_t row_read_handler;
54  /*! \brief Opaque pointer passed to row_read_handler. */
56 };
57 
58 #endif
59 /*- End of file ------------------------------------------------------------*/