00001 /* 00002 * SpanDSP - a series of DSP components for telephony 00003 * 00004 * gsm0610.h - GSM 06.10 full rate speech codec. 00005 * 00006 * Written by Steve Underwood <steveu@coppice.org> 00007 * 00008 * Copyright (C) 2006 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 General Public License version 2, as 00014 * 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 General Public License for more details. 00020 * 00021 * You should have received a copy of the GNU General Public License 00022 * along with this program; if not, write to the Free Software 00023 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 00024 * 00025 * $Id: gsm0610.h,v 1.10 2007/04/08 08:16:18 steveu Exp $ 00026 */ 00027 00028 #if !defined(_SPANDSP_GSM0610_H_) 00029 #define _SPANDSP_GSM0610_H_ 00030 00031 /*! \page gsm0610_page GSM 06.10 encoding and decoding 00032 \section gsm0610_page_sec_1 What does it do? 00033 00034 The GSM 06.10 module is an version of the widely used GSM FR codec software 00035 available from http://kbs.cs.tu-berlin.de/~jutta/toast.html. This version 00036 was produced since some versions of this codec are not bit exact, or not 00037 very efficient on modern processors. This implementation can use MMX instructions 00038 on Pentium class processors, or alternative methods on other processors. It 00039 passes all the ETSI test vectors. That is, it is a tested bit exact implementation. 00040 00041 This implementation supports encoded data in one of three packing formats: 00042 - Unpacked, with the 76 parameters of a GSM 06.10 code frame each occupying a 00043 separate byte. (note that none of the parameters exceed 8 bits). 00044 - Packed the the 33 byte per frame, used for VoIP, where 4 bits per frame are wasted. 00045 - Packed in WAV49 format, where 2 frames are packed into 65 bytes. 00046 00047 \section gsm0610_page_sec_2 How does it work? 00048 ???. 00049 */ 00050 00051 enum 00052 { 00053 GSM0610_PACKING_NONE, 00054 GSM0610_PACKING_WAV49, 00055 GSM0610_PACKING_VOIP 00056 }; 00057 00058 /*! 00059 GSM 06.10 FR codec unpacked frame. 00060 */ 00061 typedef struct 00062 { 00063 int16_t LARc[8]; 00064 int16_t Nc[4]; 00065 int16_t bc[4]; 00066 int16_t Mc[4]; 00067 int16_t xmaxc[4]; 00068 int16_t xMc[4][13]; 00069 } gsm0610_frame_t; 00070 00071 /*! 00072 GSM 06.10 FR codec state descriptor. This defines the state of 00073 a single working instance of the GSM 06.10 FR encoder or decoder. 00074 */ 00075 typedef struct 00076 { 00077 /*! \brief One of the packing modes */ 00078 int packing; 00079 00080 int16_t dp0[280]; 00081 00082 int16_t z1; /* preprocessing, Offset_com. */ 00083 int32_t L_z2; /* Offset_com. */ 00084 int16_t mp; /* Preemphasis */ 00085 00086 int16_t u[8]; /* short_term_delay_filter */ 00087 int16_t LARpp[2][8]; 00088 int16_t j; 00089 00090 int16_t nrp; /* long term synthesis */ 00091 int16_t v[9]; /* short term synthesis */ 00092 int16_t msr; /* decoder postprocessing */ 00093 00094 int16_t e[50]; /* encoder */ 00095 uint8_t frame_index; 00096 uint8_t frame_chain; 00097 } gsm0610_state_t; 00098 00099 #if defined(__cplusplus) 00100 extern "C" 00101 { 00102 #endif 00103 00104 /*! Initialise a GSM 06.10 encode or decode context. 00105 \param s The GSM 06.10 context 00106 \param packing One of the GSM0610_PACKING_xxx options. 00107 \return A pointer to the GSM 06.10 context, or NULL for error. */ 00108 gsm0610_state_t *gsm0610_init(gsm0610_state_t *s, int packing); 00109 00110 int gsm0610_release(gsm0610_state_t *s); 00111 00112 /*! Encode a buffer of linear PCM data to GSM 06.10. 00113 \param s The GSM 06.10 context. 00114 \param ima_data The GSM 06.10 data produced. 00115 \param amp The audio sample buffer. 00116 \param len The number of samples in the buffer. 00117 \return The number of bytes of GSM 06.10 data produced. */ 00118 int gsm0610_encode(gsm0610_state_t *s, uint8_t code[], const int16_t amp[], int quant); 00119 00120 /*! Decode a buffer of GSM 06.10 data to linear PCM. 00121 \param s The GSM 06.10 context. 00122 \param amp The audio sample buffer. 00123 \param code The GSM 06.10 data. 00124 \param quant The number of frames of GSM 06.10 data to be decoded. 00125 \return The number of samples returned. */ 00126 int gsm0610_decode(gsm0610_state_t *s, int16_t amp[], const uint8_t code[], int quant); 00127 00128 int gsm0610_pack_none(uint8_t c[], gsm0610_frame_t *s); 00129 00130 int gsm0610_pack_wav49(uint8_t c[], gsm0610_frame_t *s, int half); 00131 00132 int gsm0610_pack_voip(uint8_t c[], gsm0610_frame_t *s); 00133 00134 int gsm0610_unpack_none(gsm0610_frame_t *s, const uint8_t c[]); 00135 00136 int gsm0610_unpack_wav49(gsm0610_frame_t *s, const uint8_t c[], int half); 00137 00138 int gsm0610_unpack_voip(gsm0610_frame_t *s, const uint8_t c[]); 00139 00140 #if defined(__cplusplus) 00141 } 00142 #endif 00143 00144 #endif 00145 /*- End of include ---------------------------------------------------------*/