split support for G726-32 into RFC3551 and AAL2 packing orders, since both are in use change "G726-32" to be RFC3551 packing order, in spite of devices that use AAL2 order with this MIME type add ability to directly transcode between packing orders git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@37494 65c4cc65-6c06-0410-ace0-fbb531ad65f3
970 lines
25 KiB
C
970 lines
25 KiB
C
/*
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* Asterisk -- An open source telephony toolkit.
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*
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* Copyright (C) 1999 - 2006, Digium, Inc.
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*
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* Mark Spencer <markster@digium.com>
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* Kevin P. Fleming <kpfleming@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 (both RFC3551 and AAL2 codeword packing)
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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.726 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 identical
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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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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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/*
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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;
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}
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/* LIMD */
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a1ul = 15360 - a2p;
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if (state_ptr->a[0] < -a1ul)
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state_ptr->a[0] = -a1ul;
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else if (state_ptr->a[0] > a1ul)
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state_ptr->a[0] = a1ul;
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/* UPB : update predictor zeros b[6] */
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for (cnt = 0; cnt < 6; cnt++) {
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if (code_size == 5) /* for 40Kbps G.723 */
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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);
|
|
}
|
|
|
|
/*
|
|
* 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 (AAL2 packing) and store in buffer. */
|
|
static int g726aal2tolin_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;
|
|
unsigned 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, AAL2 packing) in outbuf */
|
|
static int lintog726aal2_framein(struct ast_trans_pvt *pvt, struct ast_frame *f)
|
|
{
|
|
struct g726_coder_pvt *tmp = pvt->pvt;
|
|
int16_t *src = f->data;
|
|
unsigned 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 decode packed 4-bit G726 values (RFC3551 packing) 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;
|
|
unsigned int i;
|
|
|
|
for (i = 0; i < f->datalen; i++) {
|
|
*dst++ = g726_decode(src[i] & 0x0f, &tmp->g726);
|
|
*dst++ = g726_decode((src[i] >> 4) & 0xf, &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, RFC3551 packing) 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;
|
|
unsigned 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++] = (d << 4) | (tmp->next_flag & 0xf);
|
|
pvt->samples += 2; /* 2 samples per byte */
|
|
tmp->next_flag = 0;
|
|
} else {
|
|
tmp->next_flag = 0x80 | d;
|
|
}
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
/*! \brief convert G726-32 RFC3551 packed data into AAL2 packed data (or vice-versa) */
|
|
static int g726tog726aal2_framein(struct ast_trans_pvt *pvt, struct ast_frame *f)
|
|
{
|
|
unsigned char *src = f->data;
|
|
unsigned char *dst = (unsigned char *) pvt->outbuf + pvt->samples;
|
|
unsigned int i;
|
|
|
|
for (i = 0; i < f->datalen; i++)
|
|
*dst++ = ((src[i] & 0xf) << 4) | (src[i] >> 4);
|
|
|
|
pvt->samples += f->samples;
|
|
pvt->datalen += f->samples; /* 1 byte/sample */
|
|
|
|
return 0;
|
|
}
|
|
|
|
static struct ast_frame *g726tolin_sample(void)
|
|
{
|
|
static struct ast_frame f = {
|
|
.frametype = AST_FRAME_VOICE,
|
|
.subclass = AST_FORMAT_G726,
|
|
.datalen = sizeof(g726_slin_ex),
|
|
.samples = sizeof(g726_slin_ex) * 2, /* 2 samples per byte */
|
|
.src = __PRETTY_FUNCTION__,
|
|
.data = g726_slin_ex,
|
|
};
|
|
|
|
return &f;
|
|
}
|
|
|
|
static struct ast_frame *lintog726_sample (void)
|
|
{
|
|
static struct ast_frame f = {
|
|
.frametype = AST_FRAME_VOICE,
|
|
.subclass = AST_FORMAT_SLINEAR,
|
|
.datalen = sizeof(slin_g726_ex),
|
|
.samples = sizeof(slin_g726_ex) / 2, /* 1 sample per 2 bytes */
|
|
.src = __PRETTY_FUNCTION__,
|
|
.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 struct ast_translator g726aal2tolin = {
|
|
.name = "g726aal2tolin",
|
|
.srcfmt = AST_FORMAT_G726_AAL2,
|
|
.dstfmt = AST_FORMAT_SLINEAR,
|
|
.newpvt = lintog726_new, /* same for both directions */
|
|
.framein = g726aal2tolin_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 lintog726aal2 = {
|
|
.name = "lintog726aal2",
|
|
.srcfmt = AST_FORMAT_SLINEAR,
|
|
.dstfmt = AST_FORMAT_G726_AAL2,
|
|
.newpvt = lintog726_new, /* same for both directions */
|
|
.framein = lintog726aal2_framein,
|
|
.sample = lintog726_sample,
|
|
.desc_size = sizeof(struct g726_coder_pvt),
|
|
.buffer_samples = BUFFER_SAMPLES,
|
|
.buf_size = BUFFER_SAMPLES / 2,
|
|
};
|
|
|
|
static struct ast_translator g726tog726aal2 = {
|
|
.name = "g726tog726aal2",
|
|
.srcfmt = AST_FORMAT_G726,
|
|
.dstfmt = AST_FORMAT_G726_AAL2,
|
|
.framein = g726tog726aal2_framein, /* same for both directions */
|
|
.sample = lintog726_sample,
|
|
.buffer_samples = BUFFER_SAMPLES,
|
|
.buf_size = BUFFER_SAMPLES,
|
|
};
|
|
|
|
static struct ast_translator g726aal2tog726 = {
|
|
.name = "g726aal2tog726",
|
|
.srcfmt = AST_FORMAT_G726_AAL2,
|
|
.dstfmt = AST_FORMAT_G726,
|
|
.framein = g726tog726aal2_framein, /* same for both directions */
|
|
.sample = lintog726_sample,
|
|
.buffer_samples = BUFFER_SAMPLES,
|
|
.buf_size = BUFFER_SAMPLES,
|
|
};
|
|
|
|
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);
|
|
}
|
|
|
|
static int reload(void *mod)
|
|
{
|
|
parse_config();
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int unload_module (void *mod)
|
|
{
|
|
int res = 0;
|
|
|
|
res |= ast_unregister_translator(&g726tolin);
|
|
res |= ast_unregister_translator(&lintog726);
|
|
|
|
res |= ast_unregister_translator(&g726aal2tolin);
|
|
res |= ast_unregister_translator(&lintog726aal2);
|
|
|
|
res |= ast_unregister_translator(&g726aal2tog726);
|
|
res |= ast_unregister_translator(&g726tog726aal2);
|
|
|
|
return res;
|
|
}
|
|
|
|
static int load_module (void *mod)
|
|
{
|
|
int res = 0;
|
|
|
|
parse_config();
|
|
|
|
res |= ast_register_translator(&g726tolin, mod);
|
|
res |= ast_register_translator(&lintog726, mod);
|
|
|
|
res |= ast_register_translator(&g726aal2tolin, mod);
|
|
res |= ast_register_translator(&lintog726aal2, mod);
|
|
|
|
res |= ast_register_translator(&g726aal2tog726, mod);
|
|
res |= ast_register_translator(&g726tog726aal2, mod);
|
|
|
|
if (res)
|
|
unload_module(mod);
|
|
|
|
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);
|