| /* |
| * This source code is a product of Sun Microsystems, Inc. and is provided |
| * for unrestricted use. Users may copy or modify this source code without |
| * charge. |
| * |
| * SUN SOURCE CODE IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING |
| * THE WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR |
| * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE. |
| * |
| * Sun source code is provided with no support and without any obligation on |
| * the part of Sun Microsystems, Inc. to assist in its use, correction, |
| * modification or enhancement. |
| * |
| * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE |
| * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY THIS SOFTWARE |
| * OR ANY PART THEREOF. |
| * |
| * In no event will Sun Microsystems, Inc. be liable for any lost revenue |
| * or profits or other special, indirect and consequential damages, even if |
| * Sun has been advised of the possibility of such damages. |
| * |
| * Sun Microsystems, Inc. |
| * 2550 Garcia Avenue |
| * Mountain View, California 94043 |
| */ |
| |
| /* |
| * g72x.c |
| * |
| * Common routines for G.721 and G.723 conversions. |
| */ |
| |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| |
| #include "g72x.h" |
| #include "g72x_priv.h" |
| |
| static G72x_STATE * g72x_state_new (void) ; |
| static int unpack_bytes (int bits, int blocksize, const unsigned char * block, short * samples) ; |
| static int pack_bytes (int bits, const short * samples, unsigned char * block) ; |
| |
| static |
| short power2 [15] = |
| { 1, 2, 4, 8, 0x10, 0x20, 0x40, 0x80, |
| 0x100, 0x200, 0x400, 0x800, 0x1000, 0x2000, 0x4000 |
| } ; |
| |
| /* |
| * quan() |
| * |
| * quantizes the input val against the table of size short integers. |
| * It returns i if table[i - 1] <= val < table[i]. |
| * |
| * Using linear search for simple coding. |
| */ |
| static |
| int quan (int val, short *table, int size) |
| { |
| int i; |
| |
| for (i = 0; i < size; i++) |
| if (val < *table++) |
| break; |
| return (i); |
| } |
| |
| /* |
| * fmult() |
| * |
| * returns the integer product of the 14-bit integer "an" and |
| * "floating point" representation (4-bit exponent, 6-bit mantessa) "srn". |
| */ |
| static |
| int fmult (int an, int srn) |
| { |
| short anmag, anexp, anmant; |
| short wanexp, wanmant; |
| short retval; |
| |
| anmag = (an > 0) ? an : ((-an) & 0x1FFF); |
| anexp = quan(anmag, power2, 15) - 6; |
| anmant = (anmag == 0) ? 32 : |
| (anexp >= 0) ? anmag >> anexp : anmag << -anexp; |
| wanexp = anexp + ((srn >> 6) & 0xF) - 13; |
| |
| /* |
| ** The original was : |
| ** wanmant = (anmant * (srn & 0x3F) + 0x30) >> 4 ; |
| ** but could see no valid reason for the + 0x30. |
| ** Removed it and it improved the SNR of the codec. |
| */ |
| |
| wanmant = (anmant * (srn & 0x3F)) >> 4 ; |
| |
| retval = (wanexp >= 0) ? ((wanmant << wanexp) & 0x7FFF) : |
| (wanmant >> -wanexp); |
| |
| return (((an ^ srn) < 0) ? -retval : retval); |
| } |
| |
| static G72x_STATE * g72x_state_new (void) |
| { return calloc (1, sizeof (G72x_STATE)) ; |
| } |
| |
| /* |
| * private_init_state() |
| * |
| * This routine initializes and/or resets the G72x_PRIVATE structure |
| * pointed to by 'state_ptr'. |
| * All the initial state values are specified in the CCITT G.721 document. |
| */ |
| void private_init_state (G72x_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; |
| state_ptr->sr[cnta] = 32; |
| } |
| for (cnta = 0; cnta < 6; cnta++) { |
| state_ptr->b[cnta] = 0; |
| state_ptr->dq[cnta] = 32; |
| } |
| state_ptr->td = 0; |
| } /* private_init_state */ |
| |
| struct g72x_state * g72x_reader_init (int codec, int *blocksize, int *samplesperblock) |
| { G72x_STATE *pstate ; |
| |
| if ((pstate = g72x_state_new ()) == NULL) |
| return NULL ; |
| |
| private_init_state (pstate) ; |
| |
| pstate->encoder = NULL ; |
| |
| switch (codec) |
| { case G723_16_BITS_PER_SAMPLE : /* 2 bits per sample. */ |
| pstate->decoder = g723_16_decoder ; |
| *blocksize = G723_16_BYTES_PER_BLOCK ; |
| *samplesperblock = G723_16_SAMPLES_PER_BLOCK ; |
| pstate->codec_bits = 2 ; |
| pstate->blocksize = G723_16_BYTES_PER_BLOCK ; |
| pstate->samplesperblock = G723_16_SAMPLES_PER_BLOCK ; |
| break ; |
| |
| case G723_24_BITS_PER_SAMPLE : /* 3 bits per sample. */ |
| pstate->decoder = g723_24_decoder ; |
| *blocksize = G723_24_BYTES_PER_BLOCK ; |
| *samplesperblock = G723_24_SAMPLES_PER_BLOCK ; |
| pstate->codec_bits = 3 ; |
| pstate->blocksize = G723_24_BYTES_PER_BLOCK ; |
| pstate->samplesperblock = G723_24_SAMPLES_PER_BLOCK ; |
| break ; |
| |
| case G721_32_BITS_PER_SAMPLE : /* 4 bits per sample. */ |
| pstate->decoder = g721_decoder ; |
| *blocksize = G721_32_BYTES_PER_BLOCK ; |
| *samplesperblock = G721_32_SAMPLES_PER_BLOCK ; |
| pstate->codec_bits = 4 ; |
| pstate->blocksize = G721_32_BYTES_PER_BLOCK ; |
| pstate->samplesperblock = G721_32_SAMPLES_PER_BLOCK ; |
| break ; |
| |
| case G721_40_BITS_PER_SAMPLE : /* 5 bits per sample. */ |
| pstate->decoder = g723_40_decoder ; |
| *blocksize = G721_40_BYTES_PER_BLOCK ; |
| *samplesperblock = G721_40_SAMPLES_PER_BLOCK ; |
| pstate->codec_bits = 5 ; |
| pstate->blocksize = G721_40_BYTES_PER_BLOCK ; |
| pstate->samplesperblock = G721_40_SAMPLES_PER_BLOCK ; |
| break ; |
| |
| default : |
| free (pstate) ; |
| return NULL ; |
| } ; |
| |
| return pstate ; |
| } /* g72x_reader_init */ |
| |
| struct g72x_state * g72x_writer_init (int codec, int *blocksize, int *samplesperblock) |
| { G72x_STATE *pstate ; |
| |
| if ((pstate = g72x_state_new ()) == NULL) |
| return NULL ; |
| |
| private_init_state (pstate) ; |
| pstate->decoder = NULL ; |
| |
| switch (codec) |
| { case G723_16_BITS_PER_SAMPLE : /* 2 bits per sample. */ |
| pstate->encoder = g723_16_encoder ; |
| *blocksize = G723_16_BYTES_PER_BLOCK ; |
| *samplesperblock = G723_16_SAMPLES_PER_BLOCK ; |
| pstate->codec_bits = 2 ; |
| pstate->blocksize = G723_16_BYTES_PER_BLOCK ; |
| pstate->samplesperblock = G723_16_SAMPLES_PER_BLOCK ; |
| break ; |
| |
| case G723_24_BITS_PER_SAMPLE : /* 3 bits per sample. */ |
| pstate->encoder = g723_24_encoder ; |
| *blocksize = G723_24_BYTES_PER_BLOCK ; |
| *samplesperblock = G723_24_SAMPLES_PER_BLOCK ; |
| pstate->codec_bits = 3 ; |
| pstate->blocksize = G723_24_BYTES_PER_BLOCK ; |
| pstate->samplesperblock = G723_24_SAMPLES_PER_BLOCK ; |
| break ; |
| |
| case G721_32_BITS_PER_SAMPLE : /* 4 bits per sample. */ |
| pstate->encoder = g721_encoder ; |
| *blocksize = G721_32_BYTES_PER_BLOCK ; |
| *samplesperblock = G721_32_SAMPLES_PER_BLOCK ; |
| pstate->codec_bits = 4 ; |
| pstate->blocksize = G721_32_BYTES_PER_BLOCK ; |
| pstate->samplesperblock = G721_32_SAMPLES_PER_BLOCK ; |
| break ; |
| |
| case G721_40_BITS_PER_SAMPLE : /* 5 bits per sample. */ |
| pstate->encoder = g723_40_encoder ; |
| *blocksize = G721_40_BYTES_PER_BLOCK ; |
| *samplesperblock = G721_40_SAMPLES_PER_BLOCK ; |
| pstate->codec_bits = 5 ; |
| pstate->blocksize = G721_40_BYTES_PER_BLOCK ; |
| pstate->samplesperblock = G721_40_SAMPLES_PER_BLOCK ; |
| break ; |
| |
| default : |
| free (pstate) ; |
| return NULL ; |
| } ; |
| |
| return pstate ; |
| } /* g72x_writer_init */ |
| |
| int g72x_decode_block (G72x_STATE *pstate, const unsigned char *block, short *samples) |
| { int k, count ; |
| |
| count = unpack_bytes (pstate->codec_bits, pstate->blocksize, block, samples) ; |
| |
| for (k = 0 ; k < count ; k++) |
| samples [k] = pstate->decoder (samples [k], pstate) ; |
| |
| return 0 ; |
| } /* g72x_decode_block */ |
| |
| int g72x_encode_block (G72x_STATE *pstate, short *samples, unsigned char *block) |
| { int k, count ; |
| |
| for (k = 0 ; k < pstate->samplesperblock ; k++) |
| samples [k] = pstate->encoder (samples [k], pstate) ; |
| |
| count = pack_bytes (pstate->codec_bits, samples, block) ; |
| |
| return count ; |
| } /* g72x_encode_block */ |
| |
| /* |
| * predictor_zero() |
| * |
| * computes the estimated signal from 6-zero predictor. |
| * |
| */ |
| int predictor_zero (G72x_STATE *state_ptr) |
| { |
| int i; |
| int sezi; |
| |
| sezi = fmult(state_ptr->b[0] >> 2, state_ptr->dq[0]); |
| for (i = 1; i < 6; i++) /* ACCUM */ |
| sezi += fmult(state_ptr->b[i] >> 2, state_ptr->dq[i]); |
| return (sezi); |
| } |
| /* |
| * predictor_pole() |
| * |
| * computes the estimated signal from 2-pole predictor. |
| * |
| */ |
| int predictor_pole(G72x_STATE *state_ptr) |
| { |
| return (fmult(state_ptr->a[1] >> 2, state_ptr->sr[1]) + |
| fmult(state_ptr->a[0] >> 2, state_ptr->sr[0])); |
| } |
| /* |
| * step_size() |
| * |
| * computes the quantization step size of the adaptive quantizer. |
| * |
| */ |
| int step_size (G72x_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. |
| */ |
| int quantize( |
| int d, /* Raw difference signal sample */ |
| int y, /* Step size multiplier */ |
| short *table, /* quantization table */ |
| int size) /* table size of short integers */ |
| { |
| short dqm; /* Magnitude of 'd' */ |
| short expon; /* Integer part of base 2 log of 'd' */ |
| short mant; /* Fractional part of base 2 log */ |
| short dl; /* Log of magnitude of 'd' */ |
| short dln; /* Step size scale factor normalized log */ |
| int i; |
| |
| /* |
| * LOG |
| * |
| * Compute base 2 log of 'd', and store in 'dl'. |
| */ |
| dqm = abs(d); |
| expon = quan(dqm >> 1, power2, 15); |
| mant = ((dqm << 7) >> expon) & 0x7F; /* Fractional portion. */ |
| dl = (expon << 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. |
| */ |
| int |
| reconstruct( |
| int sign, /* 0 for non-negative value */ |
| int dqln, /* G.72x codeword */ |
| int y) /* Step size multiplier */ |
| { |
| short dql; /* Log of 'dq' magnitude */ |
| short dex; /* Integer part of log */ |
| short dqt; |
| short dq; /* Reconstructed difference signal sample */ |
| |
| dql = dqln + (y >> 2); /* ADDA */ |
| |
| if (dql < 0) { |
| return ((sign) ? -0x8000 : 0); |
| } else { /* ANTILOG */ |
| dex = (dql >> 7) & 15; |
| dqt = 128 + (dql & 127); |
| dq = (dqt << 7) >> (14 - dex); |
| return ((sign) ? (dq - 0x8000) : dq); |
| } |
| } |
| |
| |
| /* |
| * update() |
| * |
| * updates the state variables for each output code |
| */ |
| 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 */ |
| G72x_STATE *state_ptr) /* coder state pointer */ |
| { |
| int cnt; |
| short mag, expon; /* Adaptive predictor, FLOAT A */ |
| short a2p = 0; /* LIMC */ |
| short a1ul; /* UPA1 */ |
| short pks1; /* UPA2 */ |
| short fa1; |
| char tr; /* tone/transition detector */ |
| short ylint, thr2, dqthr; |
| short ylfrac, thr1; |
| short pk0; |
| |
| pk0 = (dqsez < 0) ? 1 : 0; /* needed in updating predictor poles */ |
| |
| mag = dq & 0x7FFF; /* prediction difference magnitude */ |
| /* 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 (dq & 0x7FFF) { /* 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]; |
| /* FLOAT A : convert dq[0] to 4-bit exp, 6-bit mantissa f.p. */ |
| if (mag == 0) { |
| state_ptr->dq[0] = (dq >= 0) ? 0x20 : 0xFC20; |
| } else { |
| expon = quan(mag, power2, 15); |
| state_ptr->dq[0] = (dq >= 0) ? |
| (expon << 6) + ((mag << 6) >> expon) : |
| (expon << 6) + ((mag << 6) >> expon) - 0x400; |
| } |
| |
| state_ptr->sr[1] = state_ptr->sr[0]; |
| /* 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) { |
| expon = quan(sr, power2, 15); |
| state_ptr->sr[0] = (expon << 6) + ((sr << 6) >> expon); |
| } else if (sr > -32768) { |
| mag = -sr; |
| expon = quan(mag, power2, 15); |
| state_ptr->sr[0] = (expon << 6) + ((mag << 6) >> expon) - 0x400; |
| } else |
| state_ptr->sr[0] = (short) 0xFC20; |
| |
| /* 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; |
| |
| return ; |
| } /* update */ |
| |
| /*------------------------------------------------------------------------------ |
| */ |
| |
| static int |
| unpack_bytes (int bits, int blocksize, const unsigned char * block, short * samples) |
| { unsigned int in_buffer = 0 ; |
| unsigned char in_byte ; |
| int k, in_bits = 0, bindex = 0 ; |
| |
| for (k = 0 ; bindex <= blocksize && k < G72x_BLOCK_SIZE ; k++) |
| { if (in_bits < bits) |
| { in_byte = block [bindex++] ; |
| |
| in_buffer |= (in_byte << in_bits); |
| in_bits += 8; |
| } |
| samples [k] = in_buffer & ((1 << bits) - 1); |
| in_buffer >>= bits; |
| in_bits -= bits; |
| } ; |
| |
| return k ; |
| } /* unpack_bytes */ |
| |
| static int |
| pack_bytes (int bits, const short * samples, unsigned char * block) |
| { |
| unsigned int out_buffer = 0 ; |
| int k, bindex = 0, out_bits = 0 ; |
| unsigned char out_byte ; |
| |
| for (k = 0 ; k < G72x_BLOCK_SIZE ; k++) |
| { out_buffer |= (samples [k] << out_bits) ; |
| out_bits += bits ; |
| if (out_bits >= 8) |
| { out_byte = out_buffer & 0xFF ; |
| out_bits -= 8 ; |
| out_buffer >>= 8 ; |
| block [bindex++] = out_byte ; |
| } |
| } ; |
| |
| return bindex ; |
| } /* pack_bytes */ |
| |