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Diffstat (limited to 'trunk/codecs/codec_g726.c')
| -rw-r--r-- | trunk/codecs/codec_g726.c | 960 |
1 files changed, 960 insertions, 0 deletions
diff --git a/trunk/codecs/codec_g726.c b/trunk/codecs/codec_g726.c new file mode 100644 index 000000000..c8a671ee8 --- /dev/null +++ b/trunk/codecs/codec_g726.c @@ -0,0 +1,960 @@ +/* + * Asterisk -- An open source telephony toolkit. + * + * Copyright (C) 1999 - 2006, Digium, Inc. + * + * Mark Spencer <markster@digium.com> + * Kevin P. Fleming <kpfleming@digium.com> + * + * Based on frompcm.c and topcm.c from the Emiliano MIPL browser/ + * interpreter. See http://www.bsdtelephony.com.mx + * + * See http://www.asterisk.org for more information about + * the Asterisk project. Please do not directly contact + * any of the maintainers of this project for assistance; + * the project provides a web site, mailing lists and IRC + * channels for your use. + * + * This program is free software, distributed under the terms of + * the GNU General Public License Version 2. See the LICENSE file + * at the top of the source tree. + */ + +/*! \file + * + * \brief codec_g726.c - translate between signed linear and ITU G.726-32kbps (both RFC3551 and AAL2 codeword packing) + * + * \ingroup codecs + */ + +#include "asterisk.h" + +ASTERISK_FILE_VERSION(__FILE__, "$Revision$") + +#include "asterisk/lock.h" +#include "asterisk/linkedlists.h" +#include "asterisk/module.h" +#include "asterisk/config.h" +#include "asterisk/translate.h" +#include "asterisk/utils.h" + +#define WANT_ASM +#include "log2comp.h" + +/* define NOT_BLI to use a faster but not bit-level identical version */ +/* #define NOT_BLI */ + +#if defined(NOT_BLI) +# if defined(_MSC_VER) +typedef __int64 sint64; +# elif defined(__GNUC__) +typedef long long sint64; +# else +# error 64-bit integer type is not defined for your compiler/platform +# endif +#endif + +#define BUFFER_SAMPLES 8096 /* size for the translation buffers */ +#define BUF_SHIFT 5 + +/* Sample frame data */ + +#include "slin_g726_ex.h" +#include "g726_slin_ex.h" + +/* + * The following is the definition of the state structure + * used by the G.726 encoder and decoder to preserve their internal + * state between successive calls. The meanings of the majority + * of the state structure fields are explained in detail in the + * CCITT Recommendation G.721. The field names are essentially identical + * to variable names in the bit level description of the coding algorithm + * included in this Recommendation. + */ +struct g726_state { + long yl; /* Locked or steady state step size multiplier. */ + int yu; /* Unlocked or non-steady state step size multiplier. */ + int dms; /* Short term energy estimate. */ + int dml; /* Long term energy estimate. */ + int ap; /* Linear weighting coefficient of 'yl' and 'yu'. */ + int a[2]; /* Coefficients of pole portion of prediction filter. + * stored as fixed-point 1==2^14 */ + int b[6]; /* Coefficients of zero portion of prediction filter. + * stored as fixed-point 1==2^14 */ + int pk[2]; /* Signs of previous two samples of a partially + * reconstructed signal. */ + int dq[6]; /* Previous 6 samples of the quantized difference signal + * stored as fixed point 1==2^12, + * or in internal floating point format */ + int sr[2]; /* Previous 2 samples of the quantized difference signal + * stored as fixed point 1==2^12, + * or in internal floating point format */ + int td; /* delayed tone detect, new in 1988 version */ +}; + +static int qtab_721[7] = {-124, 80, 178, 246, 300, 349, 400}; +/* + * Maps G.721 code word to reconstructed scale factor normalized log + * magnitude values. + */ +static int _dqlntab[16] = {-2048, 4, 135, 213, 273, 323, 373, 425, + 425, 373, 323, 273, 213, 135, 4, -2048}; + +/* Maps G.721 code word to log of scale factor multiplier. */ +static int _witab[16] = {-12, 18, 41, 64, 112, 198, 355, 1122, + 1122, 355, 198, 112, 64, 41, 18, -12}; +/* + * Maps G.721 code words to a set of values whose long and short + * term averages are computed and then compared to give an indication + * how stationary (steady state) the signal is. + */ +static int _fitab[16] = {0, 0, 0, 0x200, 0x200, 0x200, 0x600, 0xE00, + 0xE00, 0x600, 0x200, 0x200, 0x200, 0, 0, 0}; + + +/* + * g72x_init_state() + * + * This routine initializes and/or resets the g726_state structure + * pointed to by 'state_ptr'. + * All the initial state values are specified in the CCITT G.721 document. + */ +static void g726_init_state(struct g726_state *state_ptr) +{ + int cnta; + + state_ptr->yl = 34816; + state_ptr->yu = 544; + state_ptr->dms = 0; + state_ptr->dml = 0; + state_ptr->ap = 0; + for (cnta = 0; cnta < 2; cnta++) { + state_ptr->a[cnta] = 0; + state_ptr->pk[cnta] = 0; +#ifdef NOT_BLI + state_ptr->sr[cnta] = 1; +#else + state_ptr->sr[cnta] = 32; +#endif + } + for (cnta = 0; cnta < 6; cnta++) { + state_ptr->b[cnta] = 0; +#ifdef NOT_BLI + state_ptr->dq[cnta] = 1; +#else + state_ptr->dq[cnta] = 32; +#endif + } + state_ptr->td = 0; +} + +/* + * quan() + * + * quantizes the input val against the table of integers. + * It returns i if table[i - 1] <= val < table[i]. + * + * Using linear search for simple coding. + */ +static int quan(int val, int *table, int size) +{ + int i; + + for (i = 0; i < size && val >= *table; ++i, ++table) + ; + return (i); +} + +#ifdef NOT_BLI /* faster non-identical version */ + +/* + * predictor_zero() + * + * computes the estimated signal from 6-zero predictor. + * + */ +static int predictor_zero(struct g726_state *state_ptr) +{ /* divide by 2 is necessary here to handle negative numbers correctly */ + int i; + sint64 sezi; + for (sezi = 0, i = 0; i < 6; i++) /* ACCUM */ + sezi += (sint64)state_ptr->b[i] * state_ptr->dq[i]; + return (int)(sezi >> 13) / 2 /* 2^14 */; +} + +/* + * predictor_pole() + * + * computes the estimated signal from 2-pole predictor. + * + */ +static int predictor_pole(struct g726_state *state_ptr) +{ /* divide by 2 is necessary here to handle negative numbers correctly */ + return (int)(((sint64)state_ptr->a[1] * state_ptr->sr[1] + + (sint64)state_ptr->a[0] * state_ptr->sr[0]) >> 13) / 2 /* 2^14 */; +} + +#else /* NOT_BLI - identical version */ +/* + * fmult() + * + * returns the integer product of the fixed-point number "an" (1==2^12) and + * "floating point" representation (4-bit exponent, 6-bit mantessa) "srn". + */ +static int fmult(int an, int srn) +{ + int anmag, anexp, anmant; + int wanexp, wanmant; + int retval; + + anmag = (an > 0) ? an : ((-an) & 0x1FFF); + anexp = ilog2(anmag) - 5; + anmant = (anmag == 0) ? 32 : + (anexp >= 0) ? anmag >> anexp : anmag << -anexp; + wanexp = anexp + ((srn >> 6) & 0xF) - 13; + + wanmant = (anmant * (srn & 077) + 0x30) >> 4; + retval = (wanexp >= 0) ? ((wanmant << wanexp) & 0x7FFF) : + (wanmant >> -wanexp); + + return (((an ^ srn) < 0) ? -retval : retval); +} + +static int predictor_zero(struct g726_state *state_ptr) +{ + int i; + int sezi; + for (sezi = 0, i = 0; i < 6; i++) /* ACCUM */ + sezi += fmult(state_ptr->b[i] >> 2, state_ptr->dq[i]); + return sezi; +} + +static int predictor_pole(struct g726_state *state_ptr) +{ + return (fmult(state_ptr->a[1] >> 2, state_ptr->sr[1]) + + fmult(state_ptr->a[0] >> 2, state_ptr->sr[0])); +} + +#endif /* NOT_BLI */ + +/* + * step_size() + * + * computes the quantization step size of the adaptive quantizer. + * + */ +static int step_size(struct g726_state *state_ptr) +{ + int y; + int dif; + int al; + + if (state_ptr->ap >= 256) + return (state_ptr->yu); + else { + y = state_ptr->yl >> 6; + dif = state_ptr->yu - y; + al = state_ptr->ap >> 2; + if (dif > 0) + y += (dif * al) >> 6; + else if (dif < 0) + y += (dif * al + 0x3F) >> 6; + return (y); + } +} + +/* + * quantize() + * + * Given a raw sample, 'd', of the difference signal and a + * quantization step size scale factor, 'y', this routine returns the + * ADPCM codeword to which that sample gets quantized. The step + * size scale factor division operation is done in the log base 2 domain + * as a subtraction. + */ +static int quantize( + int d, /* Raw difference signal sample */ + int y, /* Step size multiplier */ + int *table, /* quantization table */ + int size) /* table size of integers */ +{ + int dqm; /* Magnitude of 'd' */ + int exp; /* Integer part of base 2 log of 'd' */ + int mant; /* Fractional part of base 2 log */ + int dl; /* Log of magnitude of 'd' */ + int dln; /* Step size scale factor normalized log */ + int i; + + /* + * LOG + * + * Compute base 2 log of 'd', and store in 'dl'. + */ + dqm = abs(d); + exp = ilog2(dqm); + if (exp < 0) + exp = 0; + mant = ((dqm << 7) >> exp) & 0x7F; /* Fractional portion. */ + dl = (exp << 7) | mant; + + /* + * SUBTB + * + * "Divide" by step size multiplier. + */ + dln = dl - (y >> 2); + + /* + * QUAN + * + * Obtain codword i for 'd'. + */ + i = quan(dln, table, size); + if (d < 0) /* take 1's complement of i */ + return ((size << 1) + 1 - i); + else if (i == 0) /* take 1's complement of 0 */ + return ((size << 1) + 1); /* new in 1988 */ + else + return (i); +} + +/* + * reconstruct() + * + * Returns reconstructed difference signal 'dq' obtained from + * codeword 'i' and quantization step size scale factor 'y'. + * Multiplication is performed in log base 2 domain as addition. + */ +static int reconstruct( + int sign, /* 0 for non-negative value */ + int dqln, /* G.72x codeword */ + int y) /* Step size multiplier */ +{ + int dql; /* Log of 'dq' magnitude */ + int dex; /* Integer part of log */ + int dqt; + int dq; /* Reconstructed difference signal sample */ + + dql = dqln + (y >> 2); /* ADDA */ + + if (dql < 0) { +#ifdef NOT_BLI + return (sign) ? -1 : 1; +#else + return (sign) ? -0x8000 : 0; +#endif + } else { /* ANTILOG */ + dex = (dql >> 7) & 15; + dqt = 128 + (dql & 127); +#ifdef NOT_BLI + dq = ((dqt << 19) >> (14 - dex)); + return (sign) ? -dq : dq; +#else + dq = (dqt << 7) >> (14 - dex); + return (sign) ? (dq - 0x8000) : dq; +#endif + } +} + +/* + * update() + * + * updates the state variables for each output code + */ +static void update( + int code_size, /* distinguish 723_40 with others */ + int y, /* quantizer step size */ + int wi, /* scale factor multiplier */ + int fi, /* for long/short term energies */ + int dq, /* quantized prediction difference */ + int sr, /* reconstructed signal */ + int dqsez, /* difference from 2-pole predictor */ + struct g726_state *state_ptr) /* coder state pointer */ +{ + int cnt; + int mag; /* Adaptive predictor, FLOAT A */ +#ifndef NOT_BLI + int exp; +#endif + int a2p=0; /* LIMC */ + int a1ul; /* UPA1 */ + int pks1; /* UPA2 */ + int fa1; + int tr; /* tone/transition detector */ + int ylint, thr2, dqthr; + int ylfrac, thr1; + int pk0; + + pk0 = (dqsez < 0) ? 1 : 0; /* needed in updating predictor poles */ + +#ifdef NOT_BLI + mag = abs(dq / 0x1000); /* prediction difference magnitude */ +#else + mag = dq & 0x7FFF; /* prediction difference magnitude */ +#endif + /* TRANS */ + ylint = state_ptr->yl >> 15; /* exponent part of yl */ + ylfrac = (state_ptr->yl >> 10) & 0x1F; /* fractional part of yl */ + thr1 = (32 + ylfrac) << ylint; /* threshold */ + thr2 = (ylint > 9) ? 31 << 10 : thr1; /* limit thr2 to 31 << 10 */ + dqthr = (thr2 + (thr2 >> 1)) >> 1; /* dqthr = 0.75 * thr2 */ + if (state_ptr->td == 0) /* signal supposed voice */ + tr = 0; + else if (mag <= dqthr) /* supposed data, but small mag */ + tr = 0; /* treated as voice */ + else /* signal is data (modem) */ + tr = 1; + + /* + * Quantizer scale factor adaptation. + */ + + /* FUNCTW & FILTD & DELAY */ + /* update non-steady state step size multiplier */ + state_ptr->yu = y + ((wi - y) >> 5); + + /* LIMB */ + if (state_ptr->yu < 544) /* 544 <= yu <= 5120 */ + state_ptr->yu = 544; + else if (state_ptr->yu > 5120) + state_ptr->yu = 5120; + + /* FILTE & DELAY */ + /* update steady state step size multiplier */ + state_ptr->yl += state_ptr->yu + ((-state_ptr->yl) >> 6); + + /* + * Adaptive predictor coefficients. + */ + if (tr == 1) { /* reset a's and b's for modem signal */ + state_ptr->a[0] = 0; + state_ptr->a[1] = 0; + state_ptr->b[0] = 0; + state_ptr->b[1] = 0; + state_ptr->b[2] = 0; + state_ptr->b[3] = 0; + state_ptr->b[4] = 0; + state_ptr->b[5] = 0; + } else { /* update a's and b's */ + pks1 = pk0 ^ state_ptr->pk[0]; /* UPA2 */ + + /* update predictor pole a[1] */ + a2p = state_ptr->a[1] - (state_ptr->a[1] >> 7); + if (dqsez != 0) { + fa1 = (pks1) ? state_ptr->a[0] : -state_ptr->a[0]; + if (fa1 < -8191) /* a2p = function of fa1 */ + a2p -= 0x100; + else if (fa1 > 8191) + a2p += 0xFF; + else + a2p += fa1 >> 5; + + if (pk0 ^ state_ptr->pk[1]) + /* LIMC */ + if (a2p <= -12160) + a2p = -12288; + else if (a2p >= 12416) + a2p = 12288; + else + a2p -= 0x80; + else if (a2p <= -12416) + a2p = -12288; + else if (a2p >= 12160) + a2p = 12288; + else + a2p += 0x80; + } + + /* TRIGB & DELAY */ + state_ptr->a[1] = a2p; + + /* UPA1 */ + /* update predictor pole a[0] */ + state_ptr->a[0] -= state_ptr->a[0] >> 8; + if (dqsez != 0) { + if (pks1 == 0) + state_ptr->a[0] += 192; + else + 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); +} + +/* + * 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 int parse_config(int reload) +{ + struct ast_variable *var; + struct ast_flags config_flags = { reload ? CONFIG_FLAG_FILEUNCHANGED : 0 }; + struct ast_config *cfg = ast_config_load("codecs.conf", config_flags); + + if (cfg == NULL) + return 0; + if (cfg == CONFIG_STATUS_FILEUNCHANGED) + return 0; + for (var = ast_variable_browse(cfg, "plc"); var; var = var->next) { + if (!strcasecmp(var->name, "genericplc")) { + g726tolin.useplc = ast_true(var->value) ? 1 : 0; + ast_verb(3, "codec_g726: %susing generic PLC\n", + g726tolin.useplc ? "" : "not "); + } + } + ast_config_destroy(cfg); + return 0; +} + +static int reload(void) +{ + if (parse_config(1)) + return AST_MODULE_LOAD_DECLINE; + return AST_MODULE_LOAD_SUCCESS; +} + +static int unload_module(void) +{ + 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) +{ + int res = 0; + + + if (parse_config(0)) + return AST_MODULE_LOAD_DECLINE; + + res |= ast_register_translator(&g726tolin); + res |= ast_register_translator(&lintog726); + + res |= ast_register_translator(&g726aal2tolin); + res |= ast_register_translator(&lintog726aal2); + + res |= ast_register_translator(&g726aal2tog726); + res |= ast_register_translator(&g726tog726aal2); + + if (res) { + unload_module(); + return AST_MODULE_LOAD_FAILURE; + } + + return AST_MODULE_LOAD_SUCCESS; +} + +AST_MODULE_INFO(ASTERISK_GPL_KEY, AST_MODFLAG_DEFAULT, "ITU G.726-32kbps G726 Transcoder", + .load = load_module, + .unload = unload_module, + .reload = reload, + ); |