--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/spandsp-0.0.6pre17/src/spandsp/v18.h	Fri Jun 25 15:50:58 2010 +0200
@@ -0,0 +1,156 @@
+/*
+ * SpanDSP - a series of DSP components for telephony
+ *
+ * v18.h - V.18 text telephony for the deaf.
+ *
+ * Written by Steve Underwood <steveu@coppice.org>
+ *
+ * Copyright (C) 2004-2009 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: v18.h,v 1.6 2009/11/04 15:52:06 steveu Exp $
+ */
+ 
+/*! \file */
+
+/*! \page v18_page The V.18 text telephony protocols
+\section v18_page_sec_1 What does it do?
+
+\section v18_page_sec_2 How does it work?
+*/
+
+#if !defined(_SPANDSP_V18_H_)
+#define _SPANDSP_V18_H_
+
+typedef struct v18_state_s v18_state_t;
+
+enum
+{
+    V18_MODE_NONE = 0,
+    /* V.18 Annex A - Weitbrecht TDD at 45.45bps, half-duplex, 5 bit baudot. */
+    V18_MODE_5BIT_45 = 1,
+    /* V.18 Annex A - Weitbrecht TDD at 50bps, half-duplex, 5 bit baudot. */
+    V18_MODE_5BIT_50 = 2,
+    /* V.18 Annex B - DTMF encoding of ASCII. */
+    V18_MODE_DTMF = 3,
+    /* V.18 Annex C - EDT 110bps, V.21, half-duplex, ASCII. */
+    V18_MODE_EDT = 4,
+    /* V.18 Annex D - 300bps, Bell 103, duplex, ASCII. */
+    V18_MODE_BELL103 = 5,
+    /* V.18 Annex E - 1200bps Videotex terminals, ASCII. */
+    V18_MODE_V23VIDEOTEX = 6,
+    /* V.18 Annex F - V.21 text telephone, V.21, duplex, ASCII. */
+    V18_MODE_V21TEXTPHONE = 7,
+    /* V.18 Annex G - V.18 text telephone mode. */
+    V18_MODE_V18TEXTPHONE = 8
+};
+
+#if defined(__cplusplus)
+extern "C"
+{
+#endif
+
+SPAN_DECLARE(logging_state_t *) v18_get_logging_state(v18_state_t *s);
+
+/*! Initialise a V.18 context.
+    \brief Initialise a V.18 context.
+    \param s The V.18 context.
+    \param calling_party TRUE if caller mode, else answerer mode.
+    \param mode Mode of operation.
+    \param put_msg A callback routine called to deliver the received text
+           to the application.
+    \param user_data An opaque pointer for the callback routine.
+    \return A pointer to the V.18 context, or NULL if there was a problem. */
+SPAN_DECLARE(v18_state_t *) v18_init(v18_state_t *s,
+                                     int calling_party,
+                                     int mode,
+                                     put_msg_func_t put_msg,
+                                     void *user_data);
+
+/*! Release a V.18 context.
+    \brief Release a V.18 context.
+    \param s The V.18 context.
+    \return 0 for OK. */
+SPAN_DECLARE(int) v18_release(v18_state_t *s);
+
+/*! Free a V.18 context.
+    \brief Release a V.18 context.
+    \param s The V.18 context.
+    \return 0 for OK. */
+SPAN_DECLARE(int) v18_free(v18_state_t *s);
+
+/*! Generate a block of V.18 audio samples.
+    \brief Generate a block of V.18 audio samples.
+    \param s The V.18 context.
+    \param amp The audio sample buffer.
+    \param max_len The number of samples to be generated.
+    \return The number of samples actually generated.
+*/
+SPAN_DECLARE_NONSTD(int) v18_tx(v18_state_t *s, int16_t amp[], int max_len);
+
+/*! Process a block of received V.18 audio samples.
+    \brief Process a block of received V.18 audio samples.
+    \param s The V.18 context.
+    \param amp The audio sample buffer.
+    \param len The number of samples in the buffer.
+*/
+SPAN_DECLARE_NONSTD(int) v18_rx(v18_state_t *s, const int16_t amp[], int len);
+
+/*! \brief Put a string to a V.18 context's input buffer.
+    \param s The V.18 context.
+    \param msg The string to be added.
+    \param len The length of the string. If negative, the string is
+           assumed to be a NULL terminated string.
+    \return The number of characters actually added. This may be less than the
+            length of the digit string, if the buffer fills up. If the string is
+            invalid, this function will return -1. */
+SPAN_DECLARE(int) v18_put(v18_state_t *s, const char msg[], int len);
+
+/*! Convert a text string to a V.18 DTMF string.
+    \brief Convert a text string to a V.18 DTMF string.
+    \param s The V.18 context.
+    \param dtmf The resulting DTMF string.
+    \param msg The text string to be converted.
+    \return The length of the DTMF string.
+*/
+SPAN_DECLARE(int) v18_encode_dtmf(v18_state_t *s, char dtmf[], const char msg[]);
+
+/*! Convert a V.18 DTMF string to a text string.
+    \brief Convert a V.18 DTMF string to a text string.
+    \param s The V.18 context.
+    \param msg The resulting test string.
+    \param dtmf The DTMF string to be converted.
+    \return The length of the text string.
+*/
+SPAN_DECLARE(int) v18_decode_dtmf(v18_state_t *s, char msg[], const char dtmf[]);
+
+SPAN_DECLARE(uint16_t) v18_encode_baudot(v18_state_t *s, uint8_t ch);
+
+SPAN_DECLARE(uint8_t) v18_decode_baudot(v18_state_t *s, uint8_t ch);
+
+/*! \brief Return a short name for an V.18 mode
+    \param mode The code for the V.18 mode.
+    \return A pointer to the name.
+*/
+SPAN_DECLARE(const char *) v18_mode_to_str(int mode);
+
+#if defined(__cplusplus)
+}
+#endif
+
+#endif
+/*- End of file ------------------------------------------------------------*/