--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/spandsp-0.0.6pre17/src/spandsp/private/t4_rx.h	Fri Jun 25 15:50:58 2010 +0200
@@ -0,0 +1,131 @@
+/*
+ * SpanDSP - a series of DSP components for telephony
+ *
+ * private/t4_rx.h - definitions for T.4 FAX receive processing
+ *
+ * Written by Steve Underwood <steveu@coppice.org>
+ *
+ * Copyright (C) 2003 Steve Underwood
+ *
+ * All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License version 2.1,
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ * $Id: t4_rx.h,v 1.6.2.8 2009/12/21 17:18:40 steveu Exp $
+ */
+
+#if !defined(_SPANDSP_PRIVATE_T4_RX_H_)
+#define _SPANDSP_PRIVATE_T4_RX_H_
+
+/*!
+    TIFF specific state information to go with T.4 compression or decompression handling.
+*/
+typedef struct
+{
+    /*! \brief The current file name. */
+    const char *file;
+    /*! \brief The libtiff context for the current TIFF file */
+    TIFF *tiff_file;
+
+    /*! \brief The number of pages in the current image file. */
+    int pages_in_file;
+
+    /*! \brief The compression type for output to the TIFF file. */
+    int32_t output_compression;
+    /*! \brief The TIFF photometric setting for the current page. */
+    uint16_t photo_metric;
+    /*! \brief The TIFF fill order setting for the current page. */
+    uint16_t fill_order;
+    /*! \brief The TIFF G3 FAX options. */
+    int32_t output_t4_options;
+
+    /* "Background" information about the FAX, which can be stored in the image file. */
+    /*! \brief The vendor of the machine which produced the file. */ 
+    const char *vendor;
+    /*! \brief The model of machine which produced the file. */ 
+    const char *model;
+    /*! \brief The local ident string. */ 
+    const char *local_ident;
+    /*! \brief The remote end's ident string. */ 
+    const char *far_ident;
+    /*! \brief The FAX sub-address. */ 
+    const char *sub_address;
+    /*! \brief The FAX DCS information, as an ASCII string. */ 
+    const char *dcs;
+
+    /*! \brief The first page to transfer. -1 to start at the beginning of the file. */
+    int start_page;
+    /*! \brief The last page to transfer. -1 to continue to the end of the file. */
+    int stop_page;
+} t4_tiff_state_t;
+
+typedef struct t4_t6_decode_state_s t4_t6_decode_state_t;
+
+/*!
+    T.4 1D, T4 2D and T6 decompressor state.
+*/
+struct t4_t6_decode_state_s
+{
+    /*! \brief Callback function to write a row of pixels to the image destination. */
+    t4_row_write_handler_t row_write_handler;
+    /*! \brief Opaque pointer passed to row_write_handler. */
+    void *row_write_user_data;
+
+    /*! \brief Incoming bit buffer for decompression. */
+    uint32_t rx_bitstream;
+    /*! \brief The number of bits currently in rx_bitstream. */
+    int rx_bits;
+    /*! \brief The number of bits to be skipped before trying to match the next code word. */
+    int rx_skip_bits;
+
+    /*! \brief 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 consecutive_eols;
+
+    /*! \brief 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 a0;
+    /*! \brief The first changing element on the reference line to the right of a0 and of
+               opposite colour to a0. */
+    int b1;
+    /*! \brief The length of the in-progress run of black or white. */
+    int run_length;
+    /*! \brief 2D horizontal mode control. */
+    int black_white;
+    /*! \brief TRUE if the current run is black */
+    int its_black;
+
+    /*! \brief The current step into the current row run-lengths buffer. */
+    int a_cursor;
+    /*! \brief The current step into the reference row run-lengths buffer. */
+    int b_cursor;
+
+    /*! \brief A pointer into the image buffer indicating where the last row begins */
+    int last_row_starts_at;
+
+    /*! \brief The current number of consecutive bad rows. */
+    int curr_bad_row_run;
+    /*! \brief The longest run of consecutive bad rows seen in the current page. */
+    int longest_bad_row_run;
+    /*! \brief The total number of bad rows in the current page. */
+    int bad_rows;
+};
+
+#endif
+/*- End of file ------------------------------------------------------------*/