--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/spandsp-0.0.6pre17/src/spandsp/telephony.h	Fri Jun 25 15:50:58 2010 +0200
@@ -0,0 +1,91 @@
+/*
+ * SpanDSP - a series of DSP components for telephony
+ *
+ * telephony.h - some very basic telephony definitions
+ *
+ * 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: telephony.h,v 1.18.4.2 2009/12/21 18:38:06 steveu Exp $
+ */
+
+#if !defined(_SPANDSP_TELEPHONY_H_)
+#define _SPANDSP_TELEPHONY_H_
+
+#if defined(_M_IX86)  ||  defined(_M_X64)
+#if defined(LIBSPANDSP_EXPORTS)
+#define SPAN_DECLARE(type)              __declspec(dllexport) type __stdcall
+#define SPAN_DECLARE_NONSTD(type)       __declspec(dllexport) type __cdecl
+#define SPAN_DECLARE_DATA               __declspec(dllexport)
+#else
+#define SPAN_DECLARE(type)              __declspec(dllimport) type __stdcall
+#define SPAN_DECLARE_NONSTD(type)       __declspec(dllimport) type __cdecl
+#define SPAN_DECLARE_DATA               __declspec(dllimport)
+#endif
+#elif defined(SPANDSP_USE_EXPORT_CAPABILITY)  &&  (defined(__GNUC__)  ||  defined(__SUNCC__))
+#define SPAN_DECLARE(type)              __attribute__((visibility("default"))) type
+#define SPAN_DECLARE_NONSTD(type)       __attribute__((visibility("default"))) type
+#define SPAN_DECLARE_DATA               __attribute__((visibility("default")))
+#else
+#define SPAN_DECLARE(type)              /**/ type
+#define SPAN_DECLARE_NONSTD(type)       /**/ type
+#define SPAN_DECLARE_DATA               /**/
+#endif
+
+#define SAMPLE_RATE                 8000
+
+/* This is based on A-law, but u-law is only 0.03dB different */
+#define DBM0_MAX_POWER              (3.14f + 3.02f)
+#define DBM0_MAX_SINE_POWER         (3.14f)
+/* This is based on the ITU definition of dbOv in G.100.1 */
+#define DBOV_MAX_POWER              (0.0f)
+#define DBOV_MAX_SINE_POWER         (-3.02f)
+
+/*! \brief A handler for pure receive. The buffer cannot be altered. */
+typedef int (span_rx_handler_t)(void *s, const int16_t amp[], int len);
+
+/*! \brief A handler for receive, where the buffer can be altered. */
+typedef int (span_mod_handler_t)(void *s, int16_t amp[], int len);
+
+/*! \brief A handler for missing receive data fill-in. */
+typedef int (span_rx_fillin_handler_t)(void *s, int len);
+
+/*! \brief A handler for transmit, where the buffer will be filled. */
+typedef int (span_tx_handler_t)(void *s, int16_t amp[], int max_len);
+
+#define ms_to_samples(t)            ((t)*(SAMPLE_RATE/1000))
+#define us_to_samples(t)            ((t)/(1000000/SAMPLE_RATE))
+
+#if !defined(FALSE)
+#define FALSE 0
+#endif
+#if !defined(TRUE)
+#define TRUE (!FALSE)
+#endif
+
+#if defined(__cplusplus)
+/* C++ doesn't seem to have sane rounding functions/macros yet */
+#if !defined(WIN32)
+#define lrint(x) ((long int) (x))
+#define lrintf(x) ((long int) (x))
+#endif
+#endif
+
+#endif
+/*- End of file ------------------------------------------------------------*/