spandsp: telephony.h Source File

00001 /*
00002  * SpanDSP - a series of DSP components for telephony
00003  *
00004  * telephony.h - some very basic telephony definitions
00005  *
00006  * Written by Steve Underwood <steveu@coppice.org>
00007  *
00008  * Copyright (C) 2003 Steve Underwood
00009  *
00010  * All rights reserved.
00011  *
00012  * This program is free software; you can redistribute it and/or modify
00013  * it under the terms of the GNU Lesser General Public License version 2.1,
00014  * as published by the Free Software Foundation.
00015  *
00016  * This program is distributed in the hope that it will be useful,
00017  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00018  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00019  * GNU Lesser General Public License for more details.
00020  *
00021  * You should have received a copy of the GNU Lesser General Public
00022  * License along with this program; if not, write to the Free Software
00023  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
00024  */
00025 
00026 #if !defined(_SPANDSP_TELEPHONY_H_)
00027 #define _SPANDSP_TELEPHONY_H_
00028 
00029 #if defined(_M_IX86)  ||  defined(_M_X64)
00030 #if defined(LIBSPANDSP_EXPORTS)
00031 #define SPAN_DECLARE(type)              __declspec(dllexport) type __stdcall
00032 #define SPAN_DECLARE_NONSTD(type)       __declspec(dllexport) type __cdecl
00033 #define SPAN_DECLARE_DATA               __declspec(dllexport)
00034 #else
00035 #define SPAN_DECLARE(type)              __declspec(dllimport) type __stdcall
00036 #define SPAN_DECLARE_NONSTD(type)       __declspec(dllimport) type __cdecl
00037 #define SPAN_DECLARE_DATA               __declspec(dllimport)
00038 #endif
00039 #elif defined(SPANDSP_USE_EXPORT_CAPABILITY)  &&  (defined(__GNUC__)  ||  defined(__SUNCC__))
00040 #define SPAN_DECLARE(type)              __attribute__((visibility("default"))) type
00041 #define SPAN_DECLARE_NONSTD(type)       __attribute__((visibility("default"))) type
00042 #define SPAN_DECLARE_DATA               __attribute__((visibility("default")))
00043 #else
00044 #define SPAN_DECLARE(type)              /**/ type
00045 #define SPAN_DECLARE_NONSTD(type)       /**/ type
00046 #define SPAN_DECLARE_DATA               /**/
00047 #endif
00048 
00049 #define SAMPLE_RATE                 8000
00050 
00051 /* This is based on A-law, but u-law is only 0.03dB different */
00052 #define DBM0_MAX_POWER              (3.14f + 3.02f)
00053 #define DBM0_MAX_SINE_POWER         (3.14f)
00054 /* This is based on the ITU definition of dbOv in G.100.1 */
00055 #define DBOV_MAX_POWER              (0.0f)
00056 #define DBOV_MAX_SINE_POWER         (-3.02f)
00057 
00058 /*! \brief A handler for pure receive. The buffer cannot be altered. */
00059 typedef int (*span_rx_handler_t)(void *s, const int16_t amp[], int len);
00060 
00061 /*! \brief A handler for receive, where the buffer can be altered. */
00062 typedef int (*span_mod_handler_t)(void *s, int16_t amp[], int len);
00063 
00064 /*! \brief A handler for missing receive data fill-in. */
00065 typedef int (*span_rx_fillin_handler_t)(void *s, int len);
00066 
00067 /*! \brief A handler for transmit, where the buffer will be filled. */
00068 typedef int (*span_tx_handler_t)(void *s, int16_t amp[], int max_len);
00069 
00070 #define ms_to_samples(t)            ((t)*(SAMPLE_RATE/1000))
00071 #define us_to_samples(t)            ((t)/(1000000/SAMPLE_RATE))
00072 
00073 #if !defined(FALSE)
00074 #define FALSE 0
00075 #endif
00076 #if !defined(TRUE)
00077 #define TRUE (!FALSE)
00078 #endif
00079 
00080 /* Fixed point constant macros */
00081 #define FP_Q_9_7(x) ((int16_t) (128.0*x + ((x >= 0.0)  ?  0.5  :  -0.5)))
00082 #define FP_Q_8_8(x) ((int16_t) (256.0*x + ((x >= 0.0)  ?  0.5  :  -0.5)))
00083 #define FP_Q_7_9(x) ((int16_t) (512.0*x + ((x >= 0.0)  ?  0.5  :  -0.5)))
00084 #define FP_Q_6_10(x) ((int16_t) (1024.0*x + ((x >= 0.0)  ?  0.5  :  -0.5)))
00085 #define FP_Q_5_11(x) ((int16_t) (2048.0*x + ((x >= 0.0)  ?  0.5  :  -0.5)))
00086 #define FP_Q_4_12(x) ((int16_t) (4096.0*x + ((x >= 0.0)  ?  0.5  :  -0.5)))
00087 #define FP_Q_3_13(x) ((int16_t) (8192.0*x + ((x >= 0.0)  ?  0.5  :  -0.5)))
00088 #define FP_Q_2_14(x) ((int16_t) (16384.0*x + ((x >= 0.0)  ?  0.5  :  -0.5)))
00089 #define FP_Q_1_15(x) ((int16_t) (32768.0*x + ((x >= 0.0)  ?  0.5  :  -0.5)))
00090 
00091 #define FP_Q_9_23(x) ((int32_t) (65536.0*128.0*x + ((x >= 0.0)  ?  0.5  :  -0.5)))
00092 #define FP_Q_8_24(x) ((int32_t) (65536.0*256.0*x + ((x >= 0.0)  ?  0.5  :  -0.5)))
00093 #define FP_Q_7_25(x) ((int32_t) (65536.0*512.0*x + ((x >= 0.0)  ?  0.5  :  -0.5)))
00094 #define FP_Q_6_26(x) ((int32_t) (65536.0*1024.0*x + ((x >= 0.0)  ?  0.5  :  -0.5)))
00095 #define FP_Q_5_27(x) ((int32_t) (65536.0*2048.0*x + ((x >= 0.0)  ?  0.5  :  -0.5)))
00096 #define FP_Q_4_28(x) ((int32_t) (65536.0*4096.0*x + ((x >= 0.0)  ?  0.5  :  -0.5)))
00097 #define FP_Q_3_29(x) ((int32_t) (65536.0*8192.0*x + ((x >= 0.0)  ?  0.5  :  -0.5)))
00098 #define FP_Q_2_30(x) ((int32_t) (65536.0*16384.0*x + ((x >= 0.0)  ?  0.5  :  -0.5)))
00099 #define FP_Q_1_31(x) ((int32_t) (65536.0*32768.0*x + ((x >= 0.0)  ?  0.5  :  -0.5)))
00100 
00101 #if defined(__cplusplus)
00102 /* C++ doesn't seem to have sane rounding functions/macros yet */
00103 #if !defined(WIN32)
00104 #define lrint(x) ((long int) (x))
00105 #define lrintf(x) ((long int) (x))
00106 #endif
00107 #endif
00108 
00109 #endif
00110 /*- End of file ------------------------------------------------------------*/