/* Decode mid/side predictors */
void silk_stereo_decode_pred(
ec_dec *psRangeDec, /* I/O Compressor data structure */
opus_int32 pred_Q13[] /* O Predictors */
)
{
opus_int n, ix[ 2 ][ 3 ];
opus_int32 low_Q13, step_Q13;
/* Entropy decoding */
n = ec_dec_icdf( psRangeDec, silk_stereo_pred_joint_iCDF, 8 );
ix[ 0 ][ 2 ] = silk_DIV32_16( n, 5 );
ix[ 1 ][ 2 ] = n - 5 * ix[ 0 ][ 2 ];
for( n = 0; n < 2; n++ ) {
ix[ n ][ 0 ] = ec_dec_icdf( psRangeDec, silk_uniform3_iCDF, 8 );
ix[ n ][ 1 ] = ec_dec_icdf( psRangeDec, silk_uniform5_iCDF, 8 );
}
/* Dequantize */
for( n = 0; n < 2; n++ ) {
ix[ n ][ 0 ] += 3 * ix[ n ][ 2 ];
low_Q13 = silk_stereo_pred_quant_Q13[ ix[ n ][ 0 ] ];
step_Q13 = silk_SMULWB( silk_stereo_pred_quant_Q13[ ix[ n ][ 0 ] + 1 ] - low_Q13,
SILK_FIX_CONST( 0.5 / STEREO_QUANT_SUB_STEPS, 16 ) );
pred_Q13[ n ] = silk_SMLABB( low_Q13, step_Q13, 2 * ix[ n ][ 1 ] + 1 );
}
/* Subtract second from first predictor (helps when actually applying these) */
pred_Q13[ 0 ] -= pred_Q13[ 1 ];
}
/* Decode mid-only flag */
void silk_stereo_decode_mid_only(
ec_dec *psRangeDec, /* I/O Compressor data structure */
opus_int *decode_only_mid /* O Flag that only mid channel has been coded */
)
{
/* Decode flag that only mid channel is coded */
*decode_only_mid = ec_dec_icdf( psRangeDec, silk_stereo_only_code_mid_iCDF, 8 );
}
/* Decodes signs of excitation */
void silk_decode_signs(
ec_dec *psRangeDec, /* I/O Compressor data structure */
opus_int pulses[], /* I/O pulse signal */
opus_int length, /* I length of input */
const opus_int signalType, /* I Signal type */
const opus_int quantOffsetType, /* I Quantization offset type */
const opus_int sum_pulses[ MAX_NB_SHELL_BLOCKS ] /* I Sum of absolute pulses per block */
)
{
opus_int i, j, p;
opus_uint8 icdf[ 2 ];
opus_int *q_ptr;
const opus_uint8 *icdf_ptr;
icdf[ 1 ] = 0;
q_ptr = pulses;
i = silk_SMULBB( 7, silk_ADD_LSHIFT( quantOffsetType, signalType, 1 ) );
icdf_ptr = &silk_sign_iCDF[ i ];
length = silk_RSHIFT( length + SHELL_CODEC_FRAME_LENGTH/2, LOG2_SHELL_CODEC_FRAME_LENGTH );
for( i = 0; i < length; i++ ) {
p = sum_pulses[ i ];
if( p > 0 ) {
icdf[ 0 ] = icdf_ptr[ silk_min( p & 0x1F, 6 ) ];
for( j = 0; j < SHELL_CODEC_FRAME_LENGTH; j++ ) {
if( q_ptr[ j ] > 0 ) {
/* attach sign */
#if 0
/* conditional implementation */
if( ec_dec_icdf( psRangeDec, icdf, 8 ) == 0 ) {
q_ptr[ j ] = -q_ptr[ j ];
}
#else
/* implementation with shift, subtraction, multiplication */
q_ptr[ j ] *= silk_dec_map( ec_dec_icdf( psRangeDec, icdf, 8 ) );
#endif
}
}
}
q_ptr += SHELL_CODEC_FRAME_LENGTH;
}
}
static inline void decode_split(
opus_int *p_child1, /* O pulse amplitude of first child subframe */
opus_int *p_child2, /* O pulse amplitude of second child subframe */
ec_dec *psRangeDec, /* I/O Compressor data structure */
const opus_int p, /* I pulse amplitude of current subframe */
const opus_uint8 *shell_table /* I table of shell cdfs */
)
{
if( p > 0 ) {
p_child1[ 0 ] = ec_dec_icdf( psRangeDec, &shell_table[ silk_shell_code_table_offsets[ p ] ], 8 );
p_child2[ 0 ] = p - p_child1[ 0 ];
} else {
p_child1[ 0 ] = 0;
p_child2[ 0 ] = 0;
}
}
SKP_INLINE void decode_split(
SKP_int *p_child1, /* O: pulse amplitude of first child subframe */
SKP_int *p_child2, /* O: pulse amplitude of second child subframe */
ec_dec *psRangeDec, /* I/O Compressor data structure */
const SKP_int p, /* I: pulse amplitude of current subframe */
const SKP_uint8 *shell_table /* I: table of shell cdfs */
)
{
if( p > 0 ) {
p_child1[ 0 ] = ec_dec_icdf( psRangeDec, &shell_table[ SKP_Silk_shell_code_table_offsets[ p ] ], 8 );
p_child2[ 0 ] = p - p_child1[ 0 ];
} else {
p_child1[ 0 ] = 0;
p_child2[ 0 ] = 0;
}
}
int main(int _argc,char **_argv){
ec_enc enc;
ec_dec dec;
long nbits;
long nbits2;
double entropy;
int ft;
int ftb;
int sz;
int i;
int ret;
unsigned int sym;
unsigned int seed;
unsigned char *ptr;
const char *env_seed;
ret=0;
entropy=0;
if (_argc > 2) {
fprintf(stderr, "Usage: %s [<seed>]\n", _argv[0]);
return 1;
}
env_seed = getenv("SEED");
if (_argc > 1)
seed = atoi(_argv[1]);
else if (env_seed)
seed = atoi(env_seed);
else
seed = time(NULL);
/*Testing encoding of raw bit values.*/
ptr = (unsigned char *)malloc(DATA_SIZE);
ec_enc_init(&enc,ptr, DATA_SIZE);
for(ft=2;ft<1024;ft++){
for(i=0;i<ft;i++){
entropy+=log(ft)*M_LOG2E;
ec_enc_uint(&enc,i,ft);
}
}
/*Testing encoding of raw bit values.*/
for(ftb=1;ftb<16;ftb++){
for(i=0;i<(1<<ftb);i++){
entropy+=ftb;
nbits=ec_tell(&enc);
ec_enc_bits(&enc,i,ftb);
nbits2=ec_tell(&enc);
if(nbits2-nbits!=ftb){
fprintf(stderr,"Used %li bits to encode %i bits directly.\n",
nbits2-nbits,ftb);
ret=-1;
}
}
}
nbits=ec_tell_frac(&enc);
ec_enc_done(&enc);
fprintf(stderr,
"Encoded %0.2lf bits of entropy to %0.2lf bits (%0.3lf%% wasted).\n",
entropy,ldexp(nbits,-3),100*(nbits-ldexp(entropy,3))/nbits);
fprintf(stderr,"Packed to %li bytes.\n",(long)ec_range_bytes(&enc));
ec_dec_init(&dec,ptr,DATA_SIZE);
for(ft=2;ft<1024;ft++){
for(i=0;i<ft;i++){
sym=ec_dec_uint(&dec,ft);
if(sym!=(unsigned)i){
fprintf(stderr,"Decoded %i instead of %i with ft of %i.\n",sym,i,ft);
ret=-1;
}
}
}
for(ftb=1;ftb<16;ftb++){
for(i=0;i<(1<<ftb);i++){
sym=ec_dec_bits(&dec,ftb);
if(sym!=(unsigned)i){
fprintf(stderr,"Decoded %i instead of %i with ftb of %i.\n",sym,i,ftb);
ret=-1;
}
}
}
nbits2=ec_tell_frac(&dec);
if(nbits!=nbits2){
fprintf(stderr,
"Reported number of bits used was %0.2lf, should be %0.2lf.\n",
ldexp(nbits2,-3),ldexp(nbits,-3));
ret=-1;
}
/*Testing an encoder bust prefers range coder data over raw bits.
This isn't a general guarantee, will only work for data that is buffered in
the encoder state and not yet stored in the user buffer, and should never
get used in practice.
It's mostly here for code coverage completeness.*/
/*Start with a 16-bit buffer.*/
ec_enc_init(&enc,ptr,2);
/*Write 7 raw bits.*/
ec_enc_bits(&enc,0x55,7);
/*Write 12.3 bits of range coder data.*/
ec_enc_uint(&enc,1,2);
ec_enc_uint(&enc,1,3);
ec_enc_uint(&enc,1,4);
ec_enc_uint(&enc,1,5);
ec_enc_uint(&enc,2,6);
ec_enc_uint(&enc,6,7);
ec_enc_done(&enc);
ec_dec_init(&dec,ptr,2);
if(!enc.error
/*The raw bits should have been overwritten by the range coder data.*/
||ec_dec_bits(&dec,7)!=0x05
/*And all the range coder data should have been encoded correctly.*/
||ec_dec_uint(&dec,2)!=1
||ec_dec_uint(&dec,3)!=1
||ec_dec_uint(&dec,4)!=1
||ec_dec_uint(&dec,5)!=1
||ec_dec_uint(&dec,6)!=2
||ec_dec_uint(&dec,7)!=6){
fprintf(stderr,"Encoder bust overwrote range coder data with raw bits.\n");
ret=-1;
}
srand(seed);
fprintf(stderr,"Testing random streams... Random seed: %u (%.4X)\n", seed, rand() % 65536);
for(i=0;i<409600;i++){
unsigned *data;
unsigned *tell;
unsigned tell_bits;
int j;
int zeros;
ft=rand()/((RAND_MAX>>(rand()%11U))+1U)+10;
sz=rand()/((RAND_MAX>>(rand()%9U))+1U);
data=(unsigned *)malloc(sz*sizeof(*data));
tell=(unsigned *)malloc((sz+1)*sizeof(*tell));
ec_enc_init(&enc,ptr,DATA_SIZE2);
zeros = rand()%13==0;
tell[0]=ec_tell_frac(&enc);
for(j=0;j<sz;j++){
if (zeros)
data[j]=0;
else
data[j]=rand()%ft;
ec_enc_uint(&enc,data[j],ft);
tell[j+1]=ec_tell_frac(&enc);
}
if (rand()%2==0)
while(ec_tell(&enc)%8 != 0)
ec_enc_uint(&enc, rand()%2, 2);
tell_bits = ec_tell(&enc);
ec_enc_done(&enc);
if(tell_bits!=(unsigned)ec_tell(&enc)){
fprintf(stderr,"ec_tell() changed after ec_enc_done(): %i instead of %i (Random seed: %u)\n",
ec_tell(&enc),tell_bits,seed);
ret=-1;
}
if ((tell_bits+7)/8 < ec_range_bytes(&enc))
{
fprintf (stderr, "ec_tell() lied, there's %i bytes instead of %d (Random seed: %u)\n",
ec_range_bytes(&enc), (tell_bits+7)/8,seed);
ret=-1;
}
ec_dec_init(&dec,ptr,DATA_SIZE2);
if(ec_tell_frac(&dec)!=tell[0]){
fprintf(stderr,
"Tell mismatch between encoder and decoder at symbol %i: %i instead of %i (Random seed: %u).\n",
0,ec_tell_frac(&dec),tell[0],seed);
}
for(j=0;j<sz;j++){
sym=ec_dec_uint(&dec,ft);
if(sym!=data[j]){
fprintf(stderr,
"Decoded %i instead of %i with ft of %i at position %i of %i (Random seed: %u).\n",
sym,data[j],ft,j,sz,seed);
ret=-1;
}
if(ec_tell_frac(&dec)!=tell[j+1]){
fprintf(stderr,
"Tell mismatch between encoder and decoder at symbol %i: %i instead of %i (Random seed: %u).\n",
j+1,ec_tell_frac(&dec),tell[j+1],seed);
}
}
free(tell);
free(data);
}
/*Test compatibility between multiple different encode/decode routines.*/
for(i=0;i<409600;i++){
unsigned *logp1;
unsigned *data;
unsigned *tell;
unsigned *enc_method;
int j;
sz=rand()/((RAND_MAX>>(rand()%9U))+1U);
logp1=(unsigned *)malloc(sz*sizeof(*logp1));
data=(unsigned *)malloc(sz*sizeof(*data));
tell=(unsigned *)malloc((sz+1)*sizeof(*tell));
enc_method=(unsigned *)malloc(sz*sizeof(*enc_method));
ec_enc_init(&enc,ptr,DATA_SIZE2);
tell[0]=ec_tell_frac(&enc);
for(j=0;j<sz;j++){
data[j]=rand()/((RAND_MAX>>1)+1);
logp1[j]=(rand()%15)+1;
enc_method[j]=rand()/((RAND_MAX>>2)+1);
switch(enc_method[j]){
case 0:{
ec_encode(&enc,data[j]?(1<<logp1[j])-1:0,
(1<<logp1[j])-(data[j]?0:1),1<<logp1[j]);
}break;
case 1:{
ec_encode_bin(&enc,data[j]?(1<<logp1[j])-1:0,
(1<<logp1[j])-(data[j]?0:1),logp1[j]);
}break;
case 2:{
ec_enc_bit_logp(&enc,data[j],logp1[j]);
}break;
case 3:{
unsigned char icdf[2];
icdf[0]=1;
icdf[1]=0;
ec_enc_icdf(&enc,data[j],icdf,logp1[j]);
}break;
}
tell[j+1]=ec_tell_frac(&enc);
}
ec_enc_done(&enc);
if((ec_tell(&enc)+7U)/8U<ec_range_bytes(&enc)){
fprintf(stderr,"tell() lied, there's %i bytes instead of %d (Random seed: %u)\n",
ec_range_bytes(&enc),(ec_tell(&enc)+7)/8,seed);
ret=-1;
}
ec_dec_init(&dec,ptr,DATA_SIZE2);
if(ec_tell_frac(&dec)!=tell[0]){
fprintf(stderr,
"Tell mismatch between encoder and decoder at symbol %i: %i instead of %i (Random seed: %u).\n",
0,ec_tell_frac(&dec),tell[0],seed);
}
for(j=0;j<sz;j++){
int fs;
int dec_method;
dec_method=rand()/((RAND_MAX>>2)+1);
switch(dec_method){
case 0:{
fs=ec_decode(&dec,1<<logp1[j]);
sym=fs>=(1<<logp1[j])-1;
ec_dec_update(&dec,sym?(1<<logp1[j])-1:0,
(1<<logp1[j])-(sym?0:1),1<<logp1[j]);
}break;
case 1:{
fs=ec_decode_bin(&dec,logp1[j]);
sym=fs>=(1<<logp1[j])-1;
ec_dec_update(&dec,sym?(1<<logp1[j])-1:0,
(1<<logp1[j])-(sym?0:1),1<<logp1[j]);
}break;
case 2:{
sym=ec_dec_bit_logp(&dec,logp1[j]);
}break;
case 3:{
unsigned char icdf[2];
icdf[0]=1;
icdf[1]=0;
sym=ec_dec_icdf(&dec,icdf,logp1[j]);
}break;
}
if(sym!=data[j]){
fprintf(stderr,
"Decoded %i instead of %i with logp1 of %i at position %i of %i (Random seed: %u).\n",
sym,data[j],logp1[j],j,sz,seed);
fprintf(stderr,"Encoding method: %i, decoding method: %i\n",
enc_method[j],dec_method);
ret=-1;
}
if(ec_tell_frac(&dec)!=tell[j+1]){
fprintf(stderr,
"Tell mismatch between encoder and decoder at symbol %i: %i instead of %i (Random seed: %u).\n",
j+1,ec_tell_frac(&dec),tell[j+1],seed);
}
}
free(enc_method);
free(tell);
free(data);
free(logp1);
}
ec_enc_init(&enc,ptr,DATA_SIZE2);
ec_enc_bit_logp(&enc,0,1);
ec_enc_bit_logp(&enc,0,1);
ec_enc_bit_logp(&enc,0,1);
ec_enc_bit_logp(&enc,0,1);
ec_enc_bit_logp(&enc,0,2);
ec_enc_patch_initial_bits(&enc,3,2);
if(enc.error){
fprintf(stderr,"patch_initial_bits failed");
ret=-1;
}
ec_enc_patch_initial_bits(&enc,0,5);
if(!enc.error){
fprintf(stderr,"patch_initial_bits didn't fail when it should have");
ret=-1;
}
ec_enc_done(&enc);
if(ec_range_bytes(&enc)!=1||ptr[0]!=192){
fprintf(stderr,"Got %d when expecting 192 for patch_initial_bits",ptr[0]);
ret=-1;
}
ec_enc_init(&enc,ptr,DATA_SIZE2);
ec_enc_bit_logp(&enc,0,1);
ec_enc_bit_logp(&enc,0,1);
ec_enc_bit_logp(&enc,1,6);
ec_enc_bit_logp(&enc,0,2);
ec_enc_patch_initial_bits(&enc,0,2);
if(enc.error){
fprintf(stderr,"patch_initial_bits failed");
ret=-1;
}
ec_enc_done(&enc);
if(ec_range_bytes(&enc)!=2||ptr[0]!=63){
fprintf(stderr,"Got %d when expecting 63 for patch_initial_bits",ptr[0]);
ret=-1;
}
ec_enc_init(&enc,ptr,2);
ec_enc_bit_logp(&enc,0,2);
for(i=0;i<48;i++){
ec_enc_bits(&enc,0,1);
}
ec_enc_done(&enc);
if(!enc.error){
fprintf(stderr,"Raw bits overfill didn't fail when it should have");
ret=-1;
}
ec_enc_init(&enc,ptr,2);
for(i=0;i<17;i++){
ec_enc_bits(&enc,0,1);
}
ec_enc_done(&enc);
if(!enc.error){
fprintf(stderr,"17 raw bits encoded in two bytes");
ret=-1;
}
free(ptr);
return ret;
}
/* Decode side-information parameters from payload */
void silk_decode_indices(
silk_decoder_state *psDec, /* I/O State */
ec_dec *psRangeDec, /* I/O Compressor data structure */
opus_int FrameIndex, /* I Frame number */
opus_int decode_LBRR, /* I Flag indicating LBRR data is being decoded */
opus_int condCoding /* I The type of conditional coding to use */
)
{
opus_int i, k, Ix;
opus_int decode_absolute_lagIndex, delta_lagIndex;
opus_int16 ec_ix[ MAX_LPC_ORDER ];
opus_uint8 pred_Q8[ MAX_LPC_ORDER ];
/*******************************************/
/* Decode signal type and quantizer offset */
/*******************************************/
if( decode_LBRR || psDec->VAD_flags[ FrameIndex ] ) {
Ix = ec_dec_icdf( psRangeDec, silk_type_offset_VAD_iCDF, 8 ) + 2;
} else {
Ix = ec_dec_icdf( psRangeDec, silk_type_offset_no_VAD_iCDF, 8 );
}
psDec->indices.signalType = (opus_int8)silk_RSHIFT( Ix, 1 );
psDec->indices.quantOffsetType = (opus_int8)( Ix & 1 );
/****************/
/* Decode gains */
/****************/
/* First subframe */
if( condCoding == CODE_CONDITIONALLY ) {
/* Conditional coding */
psDec->indices.GainsIndices[ 0 ] = (opus_int8)ec_dec_icdf( psRangeDec, silk_delta_gain_iCDF, 8 );
} else {
/* Independent coding, in two stages: MSB bits followed by 3 LSBs */
psDec->indices.GainsIndices[ 0 ] = (opus_int8)silk_LSHIFT( ec_dec_icdf( psRangeDec, silk_gain_iCDF[ psDec->indices.signalType ], 8 ), 3 );
psDec->indices.GainsIndices[ 0 ] += (opus_int8)ec_dec_icdf( psRangeDec, silk_uniform8_iCDF, 8 );
}
/* Remaining subframes */
for( i = 1; i < psDec->nb_subfr; i++ ) {
psDec->indices.GainsIndices[ i ] = (opus_int8)ec_dec_icdf( psRangeDec, silk_delta_gain_iCDF, 8 );
}
/**********************/
/* Decode LSF Indices */
/**********************/
psDec->indices.NLSFIndices[ 0 ] = (opus_int8)ec_dec_icdf( psRangeDec, &psDec->psNLSF_CB->CB1_iCDF[ ( psDec->indices.signalType >> 1 ) * psDec->psNLSF_CB->nVectors ], 8 );
silk_NLSF_unpack( ec_ix, pred_Q8, psDec->psNLSF_CB, psDec->indices.NLSFIndices[ 0 ] );
silk_assert( psDec->psNLSF_CB->order == psDec->LPC_order );
for( i = 0; i < psDec->psNLSF_CB->order; i++ ) {
Ix = ec_dec_icdf( psRangeDec, &psDec->psNLSF_CB->ec_iCDF[ ec_ix[ i ] ], 8 );
if( Ix == 0 ) {
Ix -= ec_dec_icdf( psRangeDec, silk_NLSF_EXT_iCDF, 8 );
} else if( Ix == 2 * NLSF_QUANT_MAX_AMPLITUDE ) {
Ix += ec_dec_icdf( psRangeDec, silk_NLSF_EXT_iCDF, 8 );
}
psDec->indices.NLSFIndices[ i+1 ] = (opus_int8)( Ix - NLSF_QUANT_MAX_AMPLITUDE );
}
/* Decode LSF interpolation factor */
if( psDec->nb_subfr == MAX_NB_SUBFR ) {
psDec->indices.NLSFInterpCoef_Q2 = (opus_int8)ec_dec_icdf( psRangeDec, silk_NLSF_interpolation_factor_iCDF, 8 );
} else {
psDec->indices.NLSFInterpCoef_Q2 = 4;
}
if( psDec->indices.signalType == TYPE_VOICED )
{
/*********************/
/* Decode pitch lags */
/*********************/
/* Get lag index */
decode_absolute_lagIndex = 1;
if( condCoding == CODE_CONDITIONALLY && psDec->ec_prevSignalType == TYPE_VOICED ) {
/* Decode Delta index */
delta_lagIndex = (opus_int16)ec_dec_icdf( psRangeDec, silk_pitch_delta_iCDF, 8 );
if( delta_lagIndex > 0 ) {
delta_lagIndex = delta_lagIndex - 9;
psDec->indices.lagIndex = (opus_int16)( psDec->ec_prevLagIndex + delta_lagIndex );
decode_absolute_lagIndex = 0;
}
}
if( decode_absolute_lagIndex ) {
/* Absolute decoding */
psDec->indices.lagIndex = (opus_int16)ec_dec_icdf( psRangeDec, silk_pitch_lag_iCDF, 8 ) * silk_RSHIFT( psDec->fs_kHz, 1 );
psDec->indices.lagIndex += (opus_int16)ec_dec_icdf( psRangeDec, psDec->pitch_lag_low_bits_iCDF, 8 );
}
psDec->ec_prevLagIndex = psDec->indices.lagIndex;
/* Get countour index */
psDec->indices.contourIndex = (opus_int8)ec_dec_icdf( psRangeDec, psDec->pitch_contour_iCDF, 8 );
/********************/
/* Decode LTP gains */
/********************/
/* Decode PERIndex value */
psDec->indices.PERIndex = (opus_int8)ec_dec_icdf( psRangeDec, silk_LTP_per_index_iCDF, 8 );
for( k = 0; k < psDec->nb_subfr; k++ ) {
psDec->indices.LTPIndex[ k ] = (opus_int8)ec_dec_icdf( psRangeDec, silk_LTP_gain_iCDF_ptrs[ psDec->indices.PERIndex ], 8 );
}
/**********************/
/* Decode LTP scaling */
/**********************/
if( condCoding == CODE_INDEPENDENTLY ) {
psDec->indices.LTP_scaleIndex = (opus_int8)ec_dec_icdf( psRangeDec, silk_LTPscale_iCDF, 8 );
} else {
psDec->indices.LTP_scaleIndex = 0;
}
}
psDec->ec_prevSignalType = psDec->indices.signalType;
/***************/
/* Decode seed */
/***************/
psDec->indices.Seed = (opus_int8)ec_dec_icdf( psRangeDec, silk_uniform4_iCDF, 8 );
}
void silk_decode_pulses(ec_dec * psRangeDec, /* I/O Compressor data structure */
int pulses[], /* O Excitation signal */
const int signalType, /* I Sigtype */
const int quantOffsetType, /* I quantOffsetType */
const int frame_length /* I Frame length */
)
{
int i, j, k, iter, abs_q, nLS, RateLevelIndex;
int sum_pulses[MAX_NB_SHELL_BLOCKS], nLshifts[MAX_NB_SHELL_BLOCKS];
int *pulses_ptr;
const uint8_t *cdf_ptr;
/*********************/
/* Decode rate level */
/*********************/
RateLevelIndex =
ec_dec_icdf(psRangeDec, silk_rate_levels_iCDF[signalType >> 1], 8);
/* Calculate number of shell blocks */
assert(1 << LOG2_SHELL_CODEC_FRAME_LENGTH ==
SHELL_CODEC_FRAME_LENGTH);
iter = silk_RSHIFT(frame_length, LOG2_SHELL_CODEC_FRAME_LENGTH);
if (iter * SHELL_CODEC_FRAME_LENGTH < frame_length) {
assert(frame_length == 12 * 10); /* Make sure only happens for 10 ms @ 12 kHz */
iter++;
}
/***************************************************/
/* Sum-Weighted-Pulses Decoding */
/***************************************************/
cdf_ptr = silk_pulses_per_block_iCDF[RateLevelIndex];
for (i = 0; i < iter; i++) {
nLshifts[i] = 0;
sum_pulses[i] = ec_dec_icdf(psRangeDec, cdf_ptr, 8);
/* LSB indication */
while (sum_pulses[i] == MAX_PULSES + 1) {
nLshifts[i]++;
/* When we've already got 10 LSBs, we shift the table to not allow (MAX_PULSES + 1) */
sum_pulses[i] = ec_dec_icdf(psRangeDec,
silk_pulses_per_block_iCDF
[N_RATE_LEVELS - 1] +
(nLshifts[i] == 10), 8);
}
}
/***************************************************/
/* Shell decoding */
/***************************************************/
for (i = 0; i < iter; i++) {
if (sum_pulses[i] > 0) {
silk_shell_decoder(&pulses
[silk_SMULBB
(i, SHELL_CODEC_FRAME_LENGTH)],
psRangeDec, sum_pulses[i]);
} else {
memzero(&pulses[silk_SMULBB(i, SHELL_CODEC_FRAME_LENGTH)],
SHELL_CODEC_FRAME_LENGTH * sizeof(int));
}
}
/***************************************************/
/* LSB Decoding */
/***************************************************/
for (i = 0; i < iter; i++) {
if (nLshifts[i] > 0) {
nLS = nLshifts[i];
pulses_ptr =
&pulses[silk_SMULBB(i, SHELL_CODEC_FRAME_LENGTH)];
for (k = 0; k < SHELL_CODEC_FRAME_LENGTH; k++) {
abs_q = pulses_ptr[k];
for (j = 0; j < nLS; j++) {
abs_q = silk_LSHIFT(abs_q, 1);
abs_q +=
ec_dec_icdf(psRangeDec,
silk_lsb_iCDF, 8);
}
pulses_ptr[k] = abs_q;
}
/* Mark the number of pulses non-zero for sign decoding. */
sum_pulses[i] |= nLS << 5;
}
}
/****************************************/
/* Decode and add signs to pulse signal */
/****************************************/
silk_decode_signs(psRangeDec, pulses, frame_length, signalType,
quantOffsetType, sum_pulses);
}
SKP_int SKP_Silk_decode_frame(
SKP_Silk_decoder_state *psDec, /* I/O Pointer to Silk decoder state */
ec_dec *psRangeDec, /* I/O Compressor data structure */
SKP_int16 pOut[], /* O Pointer to output speech frame */
SKP_int32 *pN, /* O Pointer to size of output frame */
const SKP_int nBytes, /* I Payload length */
SKP_int lostFlag /* I 0: no loss, 1 loss, 2 decode fec */
)
{
SKP_Silk_decoder_control sDecCtrl;
SKP_int i, L, mv_len, ret = 0;
SKP_int8 flags;
SKP_int32 LBRR_symbol;
SKP_int pulses[ MAX_FRAME_LENGTH ];
TIC(DECODE_FRAME)
L = psDec->frame_length;
sDecCtrl.LTP_scale_Q14 = 0;
/* Safety checks */
SKP_assert( L > 0 && L <= MAX_FRAME_LENGTH );
/********************************************/
/* Decode Frame if packet is not lost */
/********************************************/
if( lostFlag != PACKET_LOST && psDec->nFramesDecoded == 0 ) {
/* First decoder call for this payload */
/* Decode VAD flags and LBRR flag */
flags = SKP_RSHIFT( psRangeDec->buf[ 0 ], 7 - psDec->nFramesPerPacket ) &
( SKP_LSHIFT( 1, psDec->nFramesPerPacket + 1 ) - 1 );
psDec->LBRR_flag = flags & 1;
for( i = psDec->nFramesPerPacket - 1; i >= 0 ; i-- ) {
flags = SKP_RSHIFT( flags, 1 );
psDec->VAD_flags[ i ] = flags & 1;
}
for( i = 0; i < psDec->nFramesPerPacket + 1; i++ ) {
ec_dec_icdf( psRangeDec, SKP_Silk_uniform2_iCDF, 8 );
}
/* Decode LBRR flags */
SKP_memset( psDec->LBRR_flags, 0, sizeof( psDec->LBRR_flags ) );
if( psDec->LBRR_flag ) {
if( psDec->nFramesPerPacket == 1 ) {
psDec->LBRR_flags[ 0 ] = 1;
} else {
LBRR_symbol = ec_dec_icdf( psRangeDec, SKP_Silk_LBRR_flags_iCDF_ptr[ psDec->nFramesPerPacket - 2 ], 8 ) + 1;
for( i = 0; i < psDec->nFramesPerPacket; i++ ) {
psDec->LBRR_flags[ i ] = SKP_RSHIFT( LBRR_symbol, i ) & 1;
}
}
}
if( lostFlag == DECODE_NORMAL ) {
/* Regular decoding: skip all LBRR data */
for( i = 0; i < psDec->nFramesPerPacket; i++ ) {
if( psDec->LBRR_flags[ i ] ) {
SKP_Silk_decode_indices( psDec, psRangeDec, i, 1 );
SKP_Silk_decode_pulses( psRangeDec, pulses, psDec->indices.signalType,
psDec->indices.quantOffsetType, psDec->frame_length );
}
}
}
}
if( lostFlag == DECODE_LBRR && psDec->LBRR_flags[ psDec->nFramesDecoded ] == 0 ) {
/* Treat absent LBRR data as lost frame */
lostFlag = PACKET_LOST;
psDec->nFramesDecoded++;
}
if( lostFlag != PACKET_LOST ) {
/*********************************************/
/* Decode quantization indices of side info */
/*********************************************/
TIC(decode_indices)
SKP_Silk_decode_indices( psDec, psRangeDec, psDec->nFramesDecoded, lostFlag );
TOC(decode_indices)
/*********************************************/
/* Decode quantization indices of excitation */
/*********************************************/
TIC(decode_pulses)
SKP_Silk_decode_pulses( psRangeDec, pulses, psDec->indices.signalType,
psDec->indices.quantOffsetType, psDec->frame_length );
TOC(decode_pulses)
/********************************************/
/* Decode parameters and pulse signal */
/********************************************/
TIC(decode_params)
SKP_Silk_decode_parameters( psDec, &sDecCtrl );
TOC(decode_params)
/* Update length. Sampling frequency may have changed */
L = psDec->frame_length;
/********************************************************/
/* Run inverse NSQ */
/********************************************************/
TIC(decode_core)
SKP_Silk_decode_core( psDec, &sDecCtrl, pOut, pulses );
TOC(decode_core)
/********************************************************/
/* Update PLC state */
/********************************************************/
SKP_Silk_PLC( psDec, &sDecCtrl, pOut, L, 0 );
psDec->lossCnt = 0;
psDec->prevSignalType = psDec->indices.signalType;
SKP_assert( psDec->prevSignalType >= 0 && psDec->prevSignalType <= 2 );
/* A frame has been decoded without errors */
psDec->first_frame_after_reset = 0;
psDec->nFramesDecoded++;
} else {
/* Handle packet loss by extrapolation */
SKP_Silk_PLC( psDec, &sDecCtrl, pOut, L, 1 );
}
/*************************/
/* Update output buffer. */
/*************************/
SKP_assert( psDec->ltp_mem_length >= psDec->frame_length );
mv_len = psDec->ltp_mem_length - psDec->frame_length;
SKP_memmove( psDec->outBuf, &psDec->outBuf[ psDec->frame_length ], mv_len * sizeof(SKP_int16) );
SKP_memcpy( &psDec->outBuf[ mv_len ], pOut, psDec->frame_length * sizeof( SKP_int16 ) );
/****************************************************************/
/* Ensure smooth connection of extrapolated and good frames */
/****************************************************************/
SKP_Silk_PLC_glue_frames( psDec, &sDecCtrl, pOut, L );
/************************************************/
/* Comfort noise generation / estimation */
/************************************************/
SKP_Silk_CNG( psDec, &sDecCtrl, pOut, L );
/********************************************/
/* HP filter output */
/********************************************/
TIC(HP_out)
SKP_Silk_biquad_alt( pOut, psDec->HP_B, psDec->HP_A, psDec->HPState, pOut, L );
TOC(HP_out)
/* Update some decoder state variables */
psDec->lagPrev = sDecCtrl.pitchL[ psDec->nb_subfr - 1 ];
/********************************************/
/* set output frame length */
/********************************************/
*pN = ( SKP_int16 )L;
TOC(DECODE_FRAME)
return ret;
}