e61d3d91f3
support the new location for zaptel.h and tonezone.h use the dependency information output by menuselect to build Makefile rules for each module for header files and libraries combine the common rules into a top-level Makefile.rules file remove all (now) unnecessary stuff from subdir Makefiles change translator API so that the newpvt() callback returns an int instead of a pointer (it no longer allocates memory) alphabetize --with-<foo> options in configure script enhance Net-SNMP support in configure script to provide a --with-netsnmp option fix support for --with-pq so that if pg-config is not found when --with-pq is specified, an error will be generated add 'optional package' usage to modules now that menuselect can output it allow res_snmp to build by default, since the new loader changes coming soon will solve the function naming problem (and users can disable it via menuselect anyway) git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@35832 65c4cc65-6c06-0410-ace0-fbb531ad65f3
859 lines
22 KiB
C
859 lines
22 KiB
C
/*
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* Asterisk -- An open source telephony toolkit.
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*
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* Copyright (C) 1999 - 2005, Digium, Inc.
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*
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* Mark Spencer <markster@digium.com>
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*
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* Based on frompcm.c and topcm.c from the Emiliano MIPL browser/
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* interpreter. See http://www.bsdtelephony.com.mx
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*
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* See http://www.asterisk.org for more information about
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* the Asterisk project. Please do not directly contact
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* any of the maintainers of this project for assistance;
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* the project provides a web site, mailing lists and IRC
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* channels for your use.
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*
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* This program is free software, distributed under the terms of
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* the GNU General Public License Version 2. See the LICENSE file
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* at the top of the source tree.
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*/
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/*! \file
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*
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* \brief codec_g726.c - translate between signed linear and ITU G.726-32kbps
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*
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* \ingroup codecs
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*/
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#include "asterisk.h"
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ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
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#include <fcntl.h>
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#include <netinet/in.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include <unistd.h>
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#include "asterisk/lock.h"
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#include "asterisk/logger.h"
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#include "asterisk/linkedlists.h"
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#include "asterisk/module.h"
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#include "asterisk/config.h"
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#include "asterisk/options.h"
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#include "asterisk/translate.h"
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#include "asterisk/channel.h"
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#include "asterisk/utils.h"
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#define WANT_ASM
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#include "log2comp.h"
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/* define NOT_BLI to use a faster but not bit-level identical version */
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/* #define NOT_BLI */
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#if defined(NOT_BLI)
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# if defined(_MSC_VER)
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typedef __int64 sint64;
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# elif defined(__GNUC__)
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typedef long long sint64;
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# else
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# error 64-bit integer type is not defined for your compiler/platform
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# endif
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#endif
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#define BUFFER_SAMPLES 8096 /* size for the translation buffers */
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#define BUF_SHIFT 5
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/* Sample frame data */
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#include "slin_g726_ex.h"
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#include "g726_slin_ex.h"
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/*
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* The following is the definition of the state structure
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* used by the G.721/G.723 encoder and decoder to preserve their internal
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* state between successive calls. The meanings of the majority
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* of the state structure fields are explained in detail in the
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* CCITT Recommendation G.721. The field names are essentially indentical
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* to variable names in the bit level description of the coding algorithm
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* included in this Recommendation.
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*/
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struct g726_state {
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long yl; /* Locked or steady state step size multiplier. */
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int yu; /* Unlocked or non-steady state step size multiplier. */
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int dms; /* Short term energy estimate. */
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int dml; /* Long term energy estimate. */
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int ap; /* Linear weighting coefficient of 'yl' and 'yu'. */
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int a[2]; /* Coefficients of pole portion of prediction filter.
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* stored as fixed-point 1==2^14 */
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int b[6]; /* Coefficients of zero portion of prediction filter.
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* stored as fixed-point 1==2^14 */
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int pk[2]; /* Signs of previous two samples of a partially
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* reconstructed signal.
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*/
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int dq[6]; /* Previous 6 samples of the quantized difference signal
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* stored as fixed point 1==2^12,
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* or in internal floating point format */
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int sr[2]; /* Previous 2 samples of the quantized difference signal
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* stored as fixed point 1==2^12,
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* or in internal floating point format */
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int td; /* delayed tone detect, new in 1988 version */
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};
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static int qtab_721[7] = {-124, 80, 178, 246, 300, 349, 400};
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/*
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* Maps G.721 code word to reconstructed scale factor normalized log
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* magnitude values.
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*/
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static int _dqlntab[16] = {-2048, 4, 135, 213, 273, 323, 373, 425,
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425, 373, 323, 273, 213, 135, 4, -2048};
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/* Maps G.721 code word to log of scale factor multiplier. */
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static int _witab[16] = {-12, 18, 41, 64, 112, 198, 355, 1122,
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1122, 355, 198, 112, 64, 41, 18, -12};
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/*
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* Maps G.721 code words to a set of values whose long and short
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* term averages are computed and then compared to give an indication
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* how stationary (steady state) the signal is.
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*/
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static int _fitab[16] = {0, 0, 0, 0x200, 0x200, 0x200, 0x600, 0xE00,
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0xE00, 0x600, 0x200, 0x200, 0x200, 0, 0, 0};
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/* Deprecated
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static int power2[15] = {1, 2, 4, 8, 0x10, 0x20, 0x40, 0x80,
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0x100, 0x200, 0x400, 0x800, 0x1000, 0x2000, 0x4000};
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*/
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/*
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* g72x_init_state()
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*
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* This routine initializes and/or resets the g726_state structure
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* pointed to by 'state_ptr'.
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* All the initial state values are specified in the CCITT G.721 document.
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*/
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static void g726_init_state(struct g726_state *state_ptr)
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{
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int cnta;
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state_ptr->yl = 34816;
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state_ptr->yu = 544;
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state_ptr->dms = 0;
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state_ptr->dml = 0;
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state_ptr->ap = 0;
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for (cnta = 0; cnta < 2; cnta++) {
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state_ptr->a[cnta] = 0;
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state_ptr->pk[cnta] = 0;
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#ifdef NOT_BLI
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state_ptr->sr[cnta] = 1;
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#else
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state_ptr->sr[cnta] = 32;
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#endif
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}
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for (cnta = 0; cnta < 6; cnta++) {
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state_ptr->b[cnta] = 0;
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#ifdef NOT_BLI
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state_ptr->dq[cnta] = 1;
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#else
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state_ptr->dq[cnta] = 32;
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#endif
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}
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state_ptr->td = 0;
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}
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/*
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* quan()
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*
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* quantizes the input val against the table of integers.
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* It returns i if table[i - 1] <= val < table[i].
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*
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* Using linear search for simple coding.
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*/
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static int quan(int val, int *table, int size)
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{
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int i;
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for (i = 0; i < size && val >= *table; ++i, ++table)
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;
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return (i);
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}
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#ifdef NOT_BLI /* faster non-identical version */
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/*
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* predictor_zero()
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*
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* computes the estimated signal from 6-zero predictor.
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*
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*/
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static int predictor_zero(struct g726_state *state_ptr)
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{ /* divide by 2 is necessary here to handle negative numbers correctly */
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int i;
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sint64 sezi;
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for (sezi = 0, i = 0; i < 6; i++) /* ACCUM */
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sezi += (sint64)state_ptr->b[i] * state_ptr->dq[i];
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return (int)(sezi >> 13) / 2 /* 2^14 */;
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}
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/*
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* predictor_pole()
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*
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* computes the estimated signal from 2-pole predictor.
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*
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*/
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static int predictor_pole(struct g726_state *state_ptr)
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{ /* divide by 2 is necessary here to handle negative numbers correctly */
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return (int)(((sint64)state_ptr->a[1] * state_ptr->sr[1] +
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(sint64)state_ptr->a[0] * state_ptr->sr[0]) >> 13) / 2 /* 2^14 */;
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}
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#else /* NOT_BLI - identical version */
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/*
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* fmult()
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*
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* returns the integer product of the fixed-point number "an" (1==2^12) and
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* "floating point" representation (4-bit exponent, 6-bit mantessa) "srn".
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*/
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static int fmult(int an, int srn)
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{
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int anmag, anexp, anmant;
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int wanexp, wanmant;
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int retval;
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anmag = (an > 0) ? an : ((-an) & 0x1FFF);
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anexp = ilog2(anmag) - 5;
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anmant = (anmag == 0) ? 32 :
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(anexp >= 0) ? anmag >> anexp : anmag << -anexp;
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wanexp = anexp + ((srn >> 6) & 0xF) - 13;
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wanmant = (anmant * (srn & 077) + 0x30) >> 4;
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retval = (wanexp >= 0) ? ((wanmant << wanexp) & 0x7FFF) :
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(wanmant >> -wanexp);
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return (((an ^ srn) < 0) ? -retval : retval);
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}
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static int predictor_zero(struct g726_state *state_ptr)
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{
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int i;
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int sezi;
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for (sezi = 0, i = 0; i < 6; i++) /* ACCUM */
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sezi += fmult(state_ptr->b[i] >> 2, state_ptr->dq[i]);
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return sezi;
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}
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static int predictor_pole(struct g726_state *state_ptr)
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{
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return (fmult(state_ptr->a[1] >> 2, state_ptr->sr[1]) +
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fmult(state_ptr->a[0] >> 2, state_ptr->sr[0]));
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}
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#endif /* NOT_BLI */
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/*
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* step_size()
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*
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* computes the quantization step size of the adaptive quantizer.
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*
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*/
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static int step_size(struct g726_state *state_ptr)
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{
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int y;
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int dif;
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int al;
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if (state_ptr->ap >= 256)
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return (state_ptr->yu);
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else {
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y = state_ptr->yl >> 6;
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dif = state_ptr->yu - y;
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al = state_ptr->ap >> 2;
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if (dif > 0)
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y += (dif * al) >> 6;
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else if (dif < 0)
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y += (dif * al + 0x3F) >> 6;
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return (y);
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}
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}
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/*
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* quantize()
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*
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* Given a raw sample, 'd', of the difference signal and a
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* quantization step size scale factor, 'y', this routine returns the
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* ADPCM codeword to which that sample gets quantized. The step
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* size scale factor division operation is done in the log base 2 domain
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* as a subtraction.
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*/
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static int quantize(
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int d, /* Raw difference signal sample */
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int y, /* Step size multiplier */
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int *table, /* quantization table */
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int size) /* table size of integers */
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{
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int dqm; /* Magnitude of 'd' */
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int exp; /* Integer part of base 2 log of 'd' */
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int mant; /* Fractional part of base 2 log */
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int dl; /* Log of magnitude of 'd' */
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int dln; /* Step size scale factor normalized log */
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int i;
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/*
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* LOG
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*
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* Compute base 2 log of 'd', and store in 'dl'.
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*/
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dqm = abs(d);
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exp = ilog2(dqm);
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if (exp < 0)
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exp = 0;
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mant = ((dqm << 7) >> exp) & 0x7F; /* Fractional portion. */
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dl = (exp << 7) | mant;
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/*
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* SUBTB
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*
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* "Divide" by step size multiplier.
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*/
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dln = dl - (y >> 2);
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/*
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* QUAN
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*
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* Obtain codword i for 'd'.
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*/
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i = quan(dln, table, size);
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if (d < 0) /* take 1's complement of i */
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return ((size << 1) + 1 - i);
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else if (i == 0) /* take 1's complement of 0 */
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return ((size << 1) + 1); /* new in 1988 */
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else
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return (i);
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}
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/*
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* reconstruct()
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*
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* Returns reconstructed difference signal 'dq' obtained from
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* codeword 'i' and quantization step size scale factor 'y'.
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* Multiplication is performed in log base 2 domain as addition.
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*/
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static int reconstruct(
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int sign, /* 0 for non-negative value */
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int dqln, /* G.72x codeword */
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int y) /* Step size multiplier */
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{
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int dql; /* Log of 'dq' magnitude */
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int dex; /* Integer part of log */
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int dqt;
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int dq; /* Reconstructed difference signal sample */
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dql = dqln + (y >> 2); /* ADDA */
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if (dql < 0) {
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#ifdef NOT_BLI
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return (sign) ? -1 : 1;
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#else
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return (sign) ? -0x8000 : 0;
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#endif
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} else { /* ANTILOG */
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dex = (dql >> 7) & 15;
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dqt = 128 + (dql & 127);
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#ifdef NOT_BLI
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dq = ((dqt << 19) >> (14 - dex));
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return (sign) ? -dq : dq;
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#else
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dq = (dqt << 7) >> (14 - dex);
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return (sign) ? (dq - 0x8000) : dq;
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#endif
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}
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}
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/*
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* update()
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*
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* updates the state variables for each output code
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*/
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static void update(
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int code_size, /* distinguish 723_40 with others */
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int y, /* quantizer step size */
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int wi, /* scale factor multiplier */
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int fi, /* for long/short term energies */
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int dq, /* quantized prediction difference */
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int sr, /* reconstructed signal */
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int dqsez, /* difference from 2-pole predictor */
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struct g726_state *state_ptr) /* coder state pointer */
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{
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int cnt;
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int mag; /* Adaptive predictor, FLOAT A */
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#ifndef NOT_BLI
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int exp;
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#endif
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int a2p=0; /* LIMC */
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int a1ul; /* UPA1 */
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int pks1; /* UPA2 */
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int fa1;
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int tr; /* tone/transition detector */
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int ylint, thr2, dqthr;
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int ylfrac, thr1;
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int pk0;
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pk0 = (dqsez < 0) ? 1 : 0; /* needed in updating predictor poles */
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#ifdef NOT_BLI
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mag = abs(dq / 0x1000); /* prediction difference magnitude */
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#else
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mag = dq & 0x7FFF; /* prediction difference magnitude */
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#endif
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/* TRANS */
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ylint = state_ptr->yl >> 15; /* exponent part of yl */
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ylfrac = (state_ptr->yl >> 10) & 0x1F; /* fractional part of yl */
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thr1 = (32 + ylfrac) << ylint; /* threshold */
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thr2 = (ylint > 9) ? 31 << 10 : thr1; /* limit thr2 to 31 << 10 */
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dqthr = (thr2 + (thr2 >> 1)) >> 1; /* dqthr = 0.75 * thr2 */
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if (state_ptr->td == 0) /* signal supposed voice */
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tr = 0;
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else if (mag <= dqthr) /* supposed data, but small mag */
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tr = 0; /* treated as voice */
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else /* signal is data (modem) */
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tr = 1;
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/*
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* Quantizer scale factor adaptation.
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*/
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/* FUNCTW & FILTD & DELAY */
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/* update non-steady state step size multiplier */
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state_ptr->yu = y + ((wi - y) >> 5);
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/* LIMB */
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if (state_ptr->yu < 544) /* 544 <= yu <= 5120 */
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state_ptr->yu = 544;
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else if (state_ptr->yu > 5120)
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state_ptr->yu = 5120;
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/* FILTE & DELAY */
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/* update steady state step size multiplier */
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state_ptr->yl += state_ptr->yu + ((-state_ptr->yl) >> 6);
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/*
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* Adaptive predictor coefficients.
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*/
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if (tr == 1) { /* reset a's and b's for modem signal */
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state_ptr->a[0] = 0;
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state_ptr->a[1] = 0;
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state_ptr->b[0] = 0;
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state_ptr->b[1] = 0;
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state_ptr->b[2] = 0;
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state_ptr->b[3] = 0;
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state_ptr->b[4] = 0;
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state_ptr->b[5] = 0;
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} else { /* update a's and b's */
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pks1 = pk0 ^ state_ptr->pk[0]; /* UPA2 */
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/* update predictor pole a[1] */
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a2p = state_ptr->a[1] - (state_ptr->a[1] >> 7);
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if (dqsez != 0) {
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fa1 = (pks1) ? state_ptr->a[0] : -state_ptr->a[0];
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if (fa1 < -8191) /* a2p = function of fa1 */
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a2p -= 0x100;
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else if (fa1 > 8191)
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a2p += 0xFF;
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else
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a2p += fa1 >> 5;
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if (pk0 ^ state_ptr->pk[1])
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/* LIMC */
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if (a2p <= -12160)
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a2p = -12288;
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else if (a2p >= 12416)
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a2p = 12288;
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else
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a2p -= 0x80;
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else if (a2p <= -12416)
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a2p = -12288;
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else if (a2p >= 12160)
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a2p = 12288;
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else
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a2p += 0x80;
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}
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/* TRIGB & DELAY */
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state_ptr->a[1] = a2p;
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/* UPA1 */
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/* update predictor pole a[0] */
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state_ptr->a[0] -= state_ptr->a[0] >> 8;
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if (dqsez != 0) {
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if (pks1 == 0)
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state_ptr->a[0] += 192;
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else
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state_ptr->a[0] -= 192;
|
|
}
|
|
/* LIMD */
|
|
a1ul = 15360 - a2p;
|
|
if (state_ptr->a[0] < -a1ul)
|
|
state_ptr->a[0] = -a1ul;
|
|
else if (state_ptr->a[0] > a1ul)
|
|
state_ptr->a[0] = a1ul;
|
|
|
|
/* UPB : update predictor zeros b[6] */
|
|
for (cnt = 0; cnt < 6; cnt++) {
|
|
if (code_size == 5) /* for 40Kbps G.723 */
|
|
state_ptr->b[cnt] -= state_ptr->b[cnt] >> 9;
|
|
else /* for G.721 and 24Kbps G.723 */
|
|
state_ptr->b[cnt] -= state_ptr->b[cnt] >> 8;
|
|
if (mag)
|
|
{ /* XOR */
|
|
if ((dq ^ state_ptr->dq[cnt]) >= 0)
|
|
state_ptr->b[cnt] += 128;
|
|
else
|
|
state_ptr->b[cnt] -= 128;
|
|
}
|
|
}
|
|
}
|
|
|
|
for (cnt = 5; cnt > 0; cnt--)
|
|
state_ptr->dq[cnt] = state_ptr->dq[cnt-1];
|
|
#ifdef NOT_BLI
|
|
state_ptr->dq[0] = dq;
|
|
#else
|
|
/* FLOAT A : convert dq[0] to 4-bit exp, 6-bit mantissa f.p. */
|
|
if (mag == 0) {
|
|
state_ptr->dq[0] = (dq >= 0) ? 0x20 : 0x20 - 0x400;
|
|
} else {
|
|
exp = ilog2(mag) + 1;
|
|
state_ptr->dq[0] = (dq >= 0) ?
|
|
(exp << 6) + ((mag << 6) >> exp) :
|
|
(exp << 6) + ((mag << 6) >> exp) - 0x400;
|
|
}
|
|
#endif
|
|
|
|
state_ptr->sr[1] = state_ptr->sr[0];
|
|
#ifdef NOT_BLI
|
|
state_ptr->sr[0] = sr;
|
|
#else
|
|
/* FLOAT B : convert sr to 4-bit exp., 6-bit mantissa f.p. */
|
|
if (sr == 0) {
|
|
state_ptr->sr[0] = 0x20;
|
|
} else if (sr > 0) {
|
|
exp = ilog2(sr) + 1;
|
|
state_ptr->sr[0] = (exp << 6) + ((sr << 6) >> exp);
|
|
} else if (sr > -0x8000) {
|
|
mag = -sr;
|
|
exp = ilog2(mag) + 1;
|
|
state_ptr->sr[0] = (exp << 6) + ((mag << 6) >> exp) - 0x400;
|
|
} else
|
|
state_ptr->sr[0] = 0x20 - 0x400;
|
|
#endif
|
|
|
|
/* DELAY A */
|
|
state_ptr->pk[1] = state_ptr->pk[0];
|
|
state_ptr->pk[0] = pk0;
|
|
|
|
/* TONE */
|
|
if (tr == 1) /* this sample has been treated as data */
|
|
state_ptr->td = 0; /* next one will be treated as voice */
|
|
else if (a2p < -11776) /* small sample-to-sample correlation */
|
|
state_ptr->td = 1; /* signal may be data */
|
|
else /* signal is voice */
|
|
state_ptr->td = 0;
|
|
|
|
/*
|
|
* Adaptation speed control.
|
|
*/
|
|
state_ptr->dms += (fi - state_ptr->dms) >> 5; /* FILTA */
|
|
state_ptr->dml += (((fi << 2) - state_ptr->dml) >> 7); /* FILTB */
|
|
|
|
if (tr == 1)
|
|
state_ptr->ap = 256;
|
|
else if (y < 1536) /* SUBTC */
|
|
state_ptr->ap += (0x200 - state_ptr->ap) >> 4;
|
|
else if (state_ptr->td == 1)
|
|
state_ptr->ap += (0x200 - state_ptr->ap) >> 4;
|
|
else if (abs((state_ptr->dms << 2) - state_ptr->dml) >=
|
|
(state_ptr->dml >> 3))
|
|
state_ptr->ap += (0x200 - state_ptr->ap) >> 4;
|
|
else
|
|
state_ptr->ap += (-state_ptr->ap) >> 4;
|
|
}
|
|
|
|
/*
|
|
* g726_decode()
|
|
*
|
|
* Description:
|
|
*
|
|
* Decodes a 4-bit code of G.726-32 encoded data of i and
|
|
* returns the resulting linear PCM, A-law or u-law value.
|
|
* return -1 for unknown out_coding value.
|
|
*/
|
|
static int g726_decode(int i, struct g726_state *state_ptr)
|
|
{
|
|
int sezi, sez, se; /* ACCUM */
|
|
int y; /* MIX */
|
|
int sr; /* ADDB */
|
|
int dq;
|
|
int dqsez;
|
|
|
|
i &= 0x0f; /* mask to get proper bits */
|
|
#ifdef NOT_BLI
|
|
sezi = predictor_zero(state_ptr);
|
|
sez = sezi;
|
|
se = sezi + predictor_pole(state_ptr); /* estimated signal */
|
|
#else
|
|
sezi = predictor_zero(state_ptr);
|
|
sez = sezi >> 1;
|
|
se = (sezi + predictor_pole(state_ptr)) >> 1; /* estimated signal */
|
|
#endif
|
|
|
|
y = step_size(state_ptr); /* dynamic quantizer step size */
|
|
|
|
dq = reconstruct(i & 8, _dqlntab[i], y); /* quantized diff. */
|
|
|
|
#ifdef NOT_BLI
|
|
sr = se + dq; /* reconst. signal */
|
|
dqsez = dq + sez; /* pole prediction diff. */
|
|
#else
|
|
sr = (dq < 0) ? se - (dq & 0x3FFF) : se + dq; /* reconst. signal */
|
|
dqsez = sr - se + sez; /* pole prediction diff. */
|
|
#endif
|
|
|
|
update(4, y, _witab[i] << 5, _fitab[i], dq, sr, dqsez, state_ptr);
|
|
|
|
#ifdef NOT_BLI
|
|
return (sr >> 10); /* sr was 26-bit dynamic range */
|
|
#else
|
|
return (sr << 2); /* sr was 14-bit dynamic range */
|
|
#endif
|
|
}
|
|
|
|
/*
|
|
* g726_encode()
|
|
*
|
|
* Encodes the input vale of linear PCM, A-law or u-law data sl and returns
|
|
* the resulting code. -1 is returned for unknown input coding value.
|
|
*/
|
|
static int g726_encode(int sl, struct g726_state *state_ptr)
|
|
{
|
|
int sezi, se, sez; /* ACCUM */
|
|
int d; /* SUBTA */
|
|
int sr; /* ADDB */
|
|
int y; /* MIX */
|
|
int dqsez; /* ADDC */
|
|
int dq, i;
|
|
|
|
#ifdef NOT_BLI
|
|
sl <<= 10; /* 26-bit dynamic range */
|
|
|
|
sezi = predictor_zero(state_ptr);
|
|
sez = sezi;
|
|
se = sezi + predictor_pole(state_ptr); /* estimated signal */
|
|
#else
|
|
sl >>= 2; /* 14-bit dynamic range */
|
|
|
|
sezi = predictor_zero(state_ptr);
|
|
sez = sezi >> 1;
|
|
se = (sezi + predictor_pole(state_ptr)) >> 1; /* estimated signal */
|
|
#endif
|
|
|
|
d = sl - se; /* estimation difference */
|
|
|
|
/* quantize the prediction difference */
|
|
y = step_size(state_ptr); /* quantizer step size */
|
|
#ifdef NOT_BLI
|
|
d /= 0x1000;
|
|
#endif
|
|
i = quantize(d, y, qtab_721, 7); /* i = G726 code */
|
|
|
|
dq = reconstruct(i & 8, _dqlntab[i], y); /* quantized est diff */
|
|
|
|
#ifdef NOT_BLI
|
|
sr = se + dq; /* reconst. signal */
|
|
dqsez = dq + sez; /* pole prediction diff. */
|
|
#else
|
|
sr = (dq < 0) ? se - (dq & 0x3FFF) : se + dq; /* reconst. signal */
|
|
dqsez = sr - se + sez; /* pole prediction diff. */
|
|
#endif
|
|
|
|
update(4, y, _witab[i] << 5, _fitab[i], dq, sr, dqsez, state_ptr);
|
|
|
|
return (i);
|
|
}
|
|
|
|
/*
|
|
* ------------ Asterisk-codec hooks. -------------------
|
|
*/
|
|
|
|
/*
|
|
* Private workspace for translating signed linear signals to G726.
|
|
* Don't bother to define two distinct structs.
|
|
*/
|
|
|
|
struct g726_coder_pvt {
|
|
/* buffer any odd byte in input - 0x80 + (value & 0xf) if present */
|
|
unsigned char next_flag;
|
|
struct g726_state g726;
|
|
};
|
|
|
|
/*! \brief init a new instance of g726_coder_pvt. */
|
|
static int lintog726_new(struct ast_trans_pvt *pvt)
|
|
{
|
|
struct g726_coder_pvt *tmp = pvt->pvt;
|
|
|
|
g726_init_state(&tmp->g726);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*! \brief decode packed 4-bit G726 values and store in buffer. */
|
|
static int g726tolin_framein (struct ast_trans_pvt *pvt, struct ast_frame *f)
|
|
{
|
|
struct g726_coder_pvt *tmp = pvt->pvt;
|
|
unsigned char *src = f->data;
|
|
int16_t *dst = (int16_t *)pvt->outbuf + pvt->samples;
|
|
int i;
|
|
|
|
for ( i = 0 ; i < f->datalen ; i++ ) {
|
|
*dst++ = g726_decode((src[i] >> 4) & 0xf, &tmp->g726);
|
|
*dst++ = g726_decode(src[i] & 0x0f, &tmp->g726);
|
|
}
|
|
pvt->samples += f->samples;
|
|
pvt->datalen += 2 * f->samples; /* 2 bytes/sample */
|
|
return 0;
|
|
}
|
|
|
|
/*! \brief compress and store data (4-bit G726 samples) in outbuf */
|
|
static int lintog726_framein(struct ast_trans_pvt *pvt, struct ast_frame *f)
|
|
{
|
|
struct g726_coder_pvt *tmp = pvt->pvt;
|
|
int16_t *src = f->data;
|
|
int i;
|
|
for ( i = 0; i < f->samples; i++ ) {
|
|
unsigned char d = g726_encode(src[i], &tmp->g726); /* this sample */
|
|
if (tmp->next_flag & 0x80) { /* merge with leftover sample */
|
|
pvt->outbuf[pvt->datalen++] = ((tmp->next_flag & 0xf)<< 4) | d;
|
|
pvt->samples += 2; /* 2 samples per byte */
|
|
tmp->next_flag = 0;
|
|
} else {
|
|
tmp->next_flag = 0x80 | d;
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/*! \brief G726ToLin_Sample */
|
|
static struct ast_frame *g726tolin_sample(void)
|
|
{
|
|
static struct ast_frame f;
|
|
f.frametype = AST_FRAME_VOICE;
|
|
f.subclass = AST_FORMAT_G726;
|
|
f.datalen = sizeof (g726_slin_ex);
|
|
f.samples = sizeof(g726_slin_ex) * 2; /* 2 samples per byte */
|
|
f.mallocd = 0;
|
|
f.offset = 0;
|
|
f.src = __PRETTY_FUNCTION__;
|
|
f.data = g726_slin_ex;
|
|
return &f;
|
|
}
|
|
|
|
/*! \brief LinToG726_Sample */
|
|
static struct ast_frame *lintog726_sample (void)
|
|
{
|
|
static struct ast_frame f;
|
|
f.frametype = AST_FRAME_VOICE;
|
|
f.subclass = AST_FORMAT_SLINEAR;
|
|
f.datalen = sizeof (slin_g726_ex);
|
|
/* Assume 8000 Hz */
|
|
f.samples = sizeof (slin_g726_ex) / 2; /* 1 sample per 2 bytes */
|
|
f.mallocd = 0;
|
|
f.offset = 0;
|
|
f.src = __PRETTY_FUNCTION__;
|
|
f.data = slin_g726_ex;
|
|
return &f;
|
|
}
|
|
|
|
static struct ast_translator g726tolin = {
|
|
.name = "g726tolin",
|
|
.srcfmt = AST_FORMAT_G726,
|
|
.dstfmt = AST_FORMAT_SLINEAR,
|
|
.newpvt = lintog726_new, /* same for both directions */
|
|
.framein = g726tolin_framein,
|
|
.sample = g726tolin_sample,
|
|
.desc_size = sizeof(struct g726_coder_pvt),
|
|
.buffer_samples = BUFFER_SAMPLES,
|
|
.buf_size = BUFFER_SAMPLES * 2,
|
|
.plc_samples = 160,
|
|
};
|
|
|
|
static struct ast_translator lintog726 = {
|
|
.name = "lintog726",
|
|
.srcfmt = AST_FORMAT_SLINEAR,
|
|
.dstfmt = AST_FORMAT_G726,
|
|
.newpvt = lintog726_new, /* same for both directions */
|
|
.framein = lintog726_framein,
|
|
.sample = lintog726_sample,
|
|
.desc_size = sizeof(struct g726_coder_pvt),
|
|
.buffer_samples = BUFFER_SAMPLES,
|
|
.buf_size = BUFFER_SAMPLES/2,
|
|
};
|
|
|
|
static void parse_config(void)
|
|
{
|
|
struct ast_variable *var;
|
|
struct ast_config *cfg = ast_config_load("codecs.conf");
|
|
if (!cfg)
|
|
return;
|
|
for (var = ast_variable_browse(cfg, "plc"); var; var = var->next) {
|
|
if (!strcasecmp(var->name, "genericplc")) {
|
|
g726tolin.useplc = ast_true(var->value) ? 1 : 0;
|
|
if (option_verbose > 2)
|
|
ast_verbose(VERBOSE_PREFIX_3 "codec_g726: %susing generic PLC\n",
|
|
g726tolin.useplc ? "" : "not ");
|
|
}
|
|
}
|
|
ast_config_destroy(cfg);
|
|
}
|
|
|
|
/*! \brief standard module glue */
|
|
|
|
static int reload(void *mod)
|
|
{
|
|
parse_config();
|
|
return 0;
|
|
}
|
|
|
|
static int unload_module (void *mod)
|
|
{
|
|
int res;
|
|
res = ast_unregister_translator (&lintog726);
|
|
res |= ast_unregister_translator (&g726tolin);
|
|
return res;
|
|
}
|
|
|
|
static int load_module (void *mod)
|
|
{
|
|
int res;
|
|
parse_config();
|
|
res = ast_register_translator (&g726tolin, mod);
|
|
if (!res)
|
|
res = ast_register_translator (&lintog726, mod);
|
|
else
|
|
ast_unregister_translator (&g726tolin);
|
|
return res;
|
|
}
|
|
|
|
static const char *description(void)
|
|
{
|
|
return "ITU G.726-32kbps G726 Transcoder";
|
|
}
|
|
|
|
static const char *key(void)
|
|
{
|
|
return ASTERISK_GPL_KEY;
|
|
}
|
|
STD_MOD(MOD_1, reload, NULL, NULL);
|