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/*
ITU-T G.729 Annex C+ - Reference C code for floating point
implementation of G.729 Annex C+
(integration of Annexes B, D and E)
Version 2.1 of October 1999
*/
/*
File : BITSCP.C
Used for the floating point version of G729B main body, G729D and G729E
*/
/*****************************************************************************/
/* bit stream manipulation routines */
/*****************************************************************************/
#include "typedef.h"
#include "ld8k.h"
#include "ld8cp.h"
#include "tab_ld8k.h"
#include "tabld8cp.h"
#include "vad.h"
#include "dtx.h"
#include "tab_dtx.h"
#include "octet.h"
/* prototypes for local functions */
static void int2bin(int value, int no_of_bits, INT16 *bitstream);
static int bin2int(int no_of_bits, INT16 *bitstream);
/*----------------------------------------------------------------------------
* prm2bits_ld8c -converts encoder parameter vector into vector of serial bits
* bits2prm_ld8c - converts serial received bits to encoder parameter vector
*----------------------------------------------------------------------------
*
* G.729 main Recommendation: 8 kb/s
*
* The transmitted parameters are:
*
* LPC: 1st codebook 7+1 bit
* 2nd codebook 5+5 bit
*
* 1st subframe:
* pitch period 8 bit
* parity check on 1st period 1 bit
* codebook index1 (positions) 13 bit
* codebook index2 (signs) 4 bit
* pitch and codebook gains 4+3 bit
*
* 2nd subframe:
* pitch period (relative) 5 bit
* codebook index1 (positions) 13 bit
* codebook index2 (signs) 4 bit
* pitch and codebook gains 4+3 bit
*
*----------------------------------------------------------------------------
*
* G.729 Annex D: 6.4 kb/s
*
* The transmitted parameters are:
*
* LPC: 1st codebook 7+1 bit
* 2nd codebook 5+5 bit
*
* 1st subframe:
* pitch period 8 bit
* codebook index1 (positions) 9 bit
* codebook index2 (signs) 2 bit
* pitch and codebook gains 3+3 bit
*
* 2nd subframe:
* pitch period (relative) 4 bit
* codebook index1 (positions) 9 bit
* codebook index2 (signs) 2 bit
* pitch and codebook gains 3+3 bit
*
*----------------------------------------------------------------------------
*
* G.729 Annex E: 11.8 kb/s
*
* The transmitted parameters in forward mode are:
*
* mode (including parity) 1+1 bit
*
* LPC: 1st codebook 7+1 bit
* 2nd codebook 5+5 bit
*
* 1st subframe:
* pitch period 8 bit
* parity check on 1st period 1 bit
* codebook index 7x5 bit
* pitch and codebook gains 4+3 bit
*
* 2nd subframe:
* pitch period (relative) 5 bit
* codebook index 7x5 bit
* pitch and codebook gains 4+3 bit
*
* The transmitted parameters in backward mode are:
*
* mode (including parity) 1+1 bit
*
* 1st subframe:
* pitch period 8 bit
* parity check on 1st period 1 bit
* codebook index 13+10+7+7+7 bit
* pitch and codebook gains 4+3 bit
*
* 2nd subframe:
* pitch period (relative) 5 bit
* codebook index 13+10+7+7+7 bit
* pitch and codebook gains 4+3 bit
*----------------------------------------------------------------------------
*/
void prm2bits_ld8c(
int prm[], /* input : encoded parameters */
INT16 bits[] /* output: serial bits */
)
{
int i;
INT16 *ptr_bits;
ptr_bits = bits;
*ptr_bits++ = SYNC_WORD; /* bit[0], at receiver this bits indicates BFI */
switch(prm[0]){
case 0 : { /* DTX: no bits transmitted */
*ptr_bits = RATE_0;
break;
}
case 1 : { /* SID: 15 bits (or 16 bits if OCTET mode) */
#ifndef OCTET_TX_MODE
*ptr_bits++ = RATE_SID;
for (i = 0; i < PRM_SIZE_SID; i++) {
int2bin(prm[i+1], bitsno_B[i], ptr_bits);
ptr_bits += bitsno_B[i];
}
#else
*ptr_bits++ = RATE_SID_OCTET;
for (i = 0; i < PRM_SIZE_SID; i++) {
int2bin(prm[i+1], bitsno_B[i], ptr_bits);
ptr_bits += bitsno_B[i];
}
*ptr_bits++ = BIT_0;
#endif
break;
}
case 2 : {
*ptr_bits++ = RATE_6400;
for (i = 0; i < PRM_SIZE_D; i++) {
int2bin(prm[i+1], bitsno_D[i], ptr_bits);
ptr_bits += bitsno_D[i];
}
break;
}
case 3 : {
*ptr_bits++ = RATE_8000;
for (i = 0; i < PRM_SIZE; i++) {
int2bin(prm[i+1], bitsno[i], ptr_bits);
ptr_bits += bitsno[i];
}
break;
}
case 4 : {
*ptr_bits++ = RATE_11800;
/* case 11.8 kbps */
if((prm[1]) == 0) { /* mode parameter */
*ptr_bits++ = BIT_0; /* "Backward / Forward" Indication bit */
*ptr_bits++ = BIT_0; /* Parity bit */
for (i = 0; i < PRM_SIZE_E_fwd-1; i++) {
int2bin(prm[i+2], bitsno_E_fwd[i], ptr_bits);
ptr_bits += bitsno_E_fwd[i];
}
}
else {
*ptr_bits++ = BIT_1; /* "Backward / Forward" Indication bit */
*ptr_bits++ = BIT_1; /* Parity bit */
for (i = 0; i < PRM_SIZE_E_bwd-1; i++) {
int2bin(prm[i+2], bitsno_E_bwd[i], ptr_bits);
ptr_bits += bitsno_E_bwd[i];
}
}
break;
}
default : {
printf("Unrecognized frame type\n");
exit(-1);
}
}
return;
}
/*----------------------------------------------------------------------------
* int2bin convert integer to binary and write the bits bitstream array
*----------------------------------------------------------------------------
*/
static void int2bin(
int value, /* input : decimal value */
int no_of_bits, /* input : number of bits to use */
INT16 *bitstream /* output: bitstream */
)
{
INT16 *pt_bitstream;
int i, bit;
pt_bitstream = bitstream + no_of_bits;
for (i = 0; i < no_of_bits; i++) {
bit = value & 0x0001; /* get lsb */
if (bit == 0)
*--pt_bitstream = BIT_0;
else
*--pt_bitstream = BIT_1;
value >>= 1;
}
return;
}
/*----------------------------------------------------------------------------
* bits2prm_ld8c - converts serial received bits to encoder parameter vector
*----------------------------------------------------------------------------
*/
void bits2prm_ld8c(
INT16 bits[], /* input : serial bits */
int prm[] /* output: decoded parameters */
)
{
int i, mode, parity_mode;
int nb_bits;
nb_bits = (int)*bits++; /* Number of bits in this frame */
switch(nb_bits){
case RATE_0 : { /* DTX: no bits transmitted */
prm[1] = 0;
break;
}
#ifndef OCTET_TX_MODE
case RATE_SID : { /* SID: 15 bits (not in OCTET mode) */
prm[1] = 1;
for (i = 0; i < PRM_SIZE_SID; i++) {
prm[i+2] = bin2int(bitsno_B[i], bits);
bits += bitsno_B[i];
}
break;
}
#else
/* the last bit of the SID bit stream under octet mode will be discarded */
case RATE_SID_OCTET : { /* SID: 16 bits (OCTET mode) */
prm[1] = 1;
for (i = 0; i < PRM_SIZE_SID; i++) {
prm[i+2] = bin2int(bitsno_B[i], bits);
bits += bitsno_B[i];
}
break;
}
#endif
case RATE_6400 : { /* G729 Annex D: 64 bits*/
prm[1] = 2;
for (i = 0; i < PRM_SIZE_D; i++) {
prm[i+2] = bin2int(bitsno_D[i], bits);
bits += bitsno_D[i];
}
break;
}
case RATE_8000 : { /* G729: 80 bits*/
prm[1] = 3;
for (i = 0; i < PRM_SIZE; i++) {
prm[i+2] = bin2int(bitsno[i], bits);
bits += bitsno[i];
}
break;
}
case RATE_11800 : { /* G729 Annex E: 118 bits*/
prm[1] = 4;
if( *bits++ == BIT_0) {
mode = 0;
}
else {
mode = 1;
}
if( *bits++ == BIT_0) {
parity_mode = 0;
}
else {
parity_mode = 1;
}
if (mode != parity_mode) { /* ==> frame erased */
for (i=0; i