/* Glues concealed frames with new good recieved frames */
void SKP_Silk_PLC_glue_frames(
SKP_Silk_decoder_state *psDec, /* I/O decoder state */
SKP_Silk_decoder_control *psDecCtrl, /* I/O Decoder control */
SKP_int16 signal[], /* I/O signal */
SKP_int length /* I length of residual */
)
{
SKP_int i, energy_shift;
SKP_int32 energy;
SKP_Silk_PLC_struct *psPLC;
psPLC = &psDec->sPLC;
if( psDec->lossCnt ) {
/* Calculate energy in concealed residual */
SKP_Silk_sum_sqr_shift( &psPLC->conc_energy, &psPLC->conc_energy_shift, signal, length );
psPLC->last_frame_lost = 1;
} else {
if( psDec->sPLC.last_frame_lost ) {
/* Calculate residual in decoded signal if last frame was lost */
SKP_Silk_sum_sqr_shift( &energy, &energy_shift, signal, length );
/* Normalize energies */
if( energy_shift > psPLC->conc_energy_shift ) {
psPLC->conc_energy = SKP_RSHIFT( psPLC->conc_energy, energy_shift - psPLC->conc_energy_shift );
} else if( energy_shift < psPLC->conc_energy_shift ) {
energy = SKP_RSHIFT( energy, psPLC->conc_energy_shift - energy_shift );
}
/* Fade in the energy difference */
if( energy > psPLC->conc_energy ) {
SKP_int32 frac_Q24, LZ;
SKP_int32 gain_Q12, slope_Q12;
LZ = SKP_Silk_CLZ32( psPLC->conc_energy );
LZ = LZ - 1;
psPLC->conc_energy = SKP_LSHIFT( psPLC->conc_energy, LZ );
energy = SKP_RSHIFT( energy, SKP_max_32( 24 - LZ, 0 ) );
frac_Q24 = SKP_DIV32( psPLC->conc_energy, SKP_max( energy, 1 ) );
gain_Q12 = SKP_Silk_SQRT_APPROX( frac_Q24 );
slope_Q12 = SKP_DIV32_16( ( 1 << 12 ) - gain_Q12, length );
for( i = 0; i < length; i++ ) {
signal[ i ] = SKP_RSHIFT( SKP_MUL( gain_Q12, signal[ i ] ), 12 );
gain_Q12 += slope_Q12;
gain_Q12 = SKP_min( gain_Q12, ( 1 << 12 ) );
}
}
}
psPLC->last_frame_lost = 0;
}
}
void SKP_Silk_detect_SWB_input(SKP_Silk_detect_SWB_state * psSWBdetect, /* (I/O) encoder state */
const int16_t samplesIn[], /* (I) input to encoder */
int nSamplesIn /* (I) length of input */
)
{
int HP_8_kHz_len, i;
int16_t in_HP_8_kHz[MAX_FRAME_LENGTH];
int32_t energy_32, shift;
/* High pass filter with cutoff at 8 khz */
HP_8_kHz_len = SKP_min_int(nSamplesIn, MAX_FRAME_LENGTH);
HP_8_kHz_len = SKP_max_int(HP_8_kHz_len, 0);
/* Cutoff around 9 khz */
/* A = conv(conv([8192,14613, 6868], [8192,12883, 7337]), [8192,11586, 7911]); */
/* B = conv(conv([575, -948, 575], [575, -221, 575]), [575, 104, 575]); */
SKP_Silk_biquad(samplesIn, SKP_Silk_SWB_detect_B_HP_Q13[0],
SKP_Silk_SWB_detect_A_HP_Q13[0],
psSWBdetect->S_HP_8_kHz[0], in_HP_8_kHz, HP_8_kHz_len);
for (i = 1; i < NB_SOS; i++) {
SKP_Silk_biquad(in_HP_8_kHz, SKP_Silk_SWB_detect_B_HP_Q13[i],
SKP_Silk_SWB_detect_A_HP_Q13[i],
psSWBdetect->S_HP_8_kHz[i], in_HP_8_kHz,
HP_8_kHz_len);
}
/* Calculate energy in HP signal */
SKP_Silk_sum_sqr_shift(&energy_32, &shift, in_HP_8_kHz, HP_8_kHz_len);
/* Count concecutive samples above threshold, after adjusting threshold for number of input samples and shift */
if (energy_32 >
SKP_RSHIFT(SKP_SMULBB(HP_8_KHZ_THRES, HP_8_kHz_len), shift)) {
psSWBdetect->ConsecSmplsAboveThres += nSamplesIn;
if (psSWBdetect->ConsecSmplsAboveThres > CONCEC_SWB_SMPLS_THRES) {
psSWBdetect->SWB_detected = 1;
}
} else {
psSWBdetect->ConsecSmplsAboveThres -= nSamplesIn;
psSWBdetect->ConsecSmplsAboveThres =
SKP_max(psSWBdetect->ConsecSmplsAboveThres, 0);
}
/* If sufficient speech activity and no SWB detected, we detect the signal as being WB */
if ((psSWBdetect->ActiveSpeech_ms > WB_DETECT_ACTIVE_SPEECH_MS_THRES)
&& (psSWBdetect->SWB_detected == 0)) {
psSWBdetect->WB_detected = 1;
}
}
/* amplitude of monic warped coefficients by using bandwidth expansion on the true coefficients */
SKP_INLINE void limit_warped_coefs(
SKP_int32 *coefs_syn_Q24,
SKP_int32 *coefs_ana_Q24,
SKP_int lambda_Q16,
SKP_int32 limit_Q24,
SKP_int order
) {
SKP_int i, iter, ind = 0;
SKP_int32 tmp, maxabs_Q24, chirp_Q16, gain_syn_Q16, gain_ana_Q16;
SKP_int32 nom_Q16, den_Q24;
/* Convert to monic coefficients */
lambda_Q16 = -lambda_Q16;
for( i = order - 1; i > 0; i-- ) {
coefs_syn_Q24[ i - 1 ] = SKP_SMLAWB( coefs_syn_Q24[ i - 1 ], coefs_syn_Q24[ i ], lambda_Q16 );
coefs_ana_Q24[ i - 1 ] = SKP_SMLAWB( coefs_ana_Q24[ i - 1 ], coefs_ana_Q24[ i ], lambda_Q16 );
}
lambda_Q16 = -lambda_Q16;
nom_Q16 = SKP_SMLAWB( SKP_FIX_CONST( 1.0, 16 ), -lambda_Q16, lambda_Q16 );
den_Q24 = SKP_SMLAWB( SKP_FIX_CONST( 1.0, 24 ), coefs_syn_Q24[ 0 ], lambda_Q16 );
gain_syn_Q16 = SKP_DIV32_varQ( nom_Q16, den_Q24, 24 );
den_Q24 = SKP_SMLAWB( SKP_FIX_CONST( 1.0, 24 ), coefs_ana_Q24[ 0 ], lambda_Q16 );
gain_ana_Q16 = SKP_DIV32_varQ( nom_Q16, den_Q24, 24 );
for( i = 0; i < order; i++ ) {
coefs_syn_Q24[ i ] = SKP_SMULWW( gain_syn_Q16, coefs_syn_Q24[ i ] );
coefs_ana_Q24[ i ] = SKP_SMULWW( gain_ana_Q16, coefs_ana_Q24[ i ] );
}
for( iter = 0; iter < 10; iter++ ) {
/* Find maximum absolute value */
maxabs_Q24 = -1;
for( i = 0; i < order; i++ ) {
tmp = SKP_max( SKP_abs_int32( coefs_syn_Q24[ i ] ), SKP_abs_int32( coefs_ana_Q24[ i ] ) );
if( tmp > maxabs_Q24 ) {
maxabs_Q24 = tmp;
ind = i;
}
}
if( maxabs_Q24 <= limit_Q24 ) {
/* Coefficients are within range - done */
return;
}
/* Convert back to true warped coefficients */
for( i = 1; i < order; i++ ) {
coefs_syn_Q24[ i - 1 ] = SKP_SMLAWB( coefs_syn_Q24[ i - 1 ], coefs_syn_Q24[ i ], lambda_Q16 );
coefs_ana_Q24[ i - 1 ] = SKP_SMLAWB( coefs_ana_Q24[ i - 1 ], coefs_ana_Q24[ i ], lambda_Q16 );
}
gain_syn_Q16 = SKP_INVERSE32_varQ( gain_syn_Q16, 32 );
gain_ana_Q16 = SKP_INVERSE32_varQ( gain_ana_Q16, 32 );
for( i = 0; i < order; i++ ) {
coefs_syn_Q24[ i ] = SKP_SMULWW( gain_syn_Q16, coefs_syn_Q24[ i ] );
coefs_ana_Q24[ i ] = SKP_SMULWW( gain_ana_Q16, coefs_ana_Q24[ i ] );
}
/* Apply bandwidth expansion */
chirp_Q16 = SKP_FIX_CONST( 0.99, 16 ) - SKP_DIV32_varQ(
SKP_SMULWB( maxabs_Q24 - limit_Q24, SKP_SMLABB( SKP_FIX_CONST( 0.8, 10 ), SKP_FIX_CONST( 0.1, 10 ), iter ) ),
SKP_MUL( maxabs_Q24, ind + 1 ), 22 );
SKP_Silk_bwexpander_32( coefs_syn_Q24, order, chirp_Q16 );
SKP_Silk_bwexpander_32( coefs_ana_Q24, order, chirp_Q16 );
/* Convert to monic warped coefficients */
lambda_Q16 = -lambda_Q16;
for( i = order - 1; i > 0; i-- ) {
coefs_syn_Q24[ i - 1 ] = SKP_SMLAWB( coefs_syn_Q24[ i - 1 ], coefs_syn_Q24[ i ], lambda_Q16 );
coefs_ana_Q24[ i - 1 ] = SKP_SMLAWB( coefs_ana_Q24[ i - 1 ], coefs_ana_Q24[ i ], lambda_Q16 );
}
lambda_Q16 = -lambda_Q16;
nom_Q16 = SKP_SMLAWB( SKP_FIX_CONST( 1.0, 16 ), -lambda_Q16, lambda_Q16 );
den_Q24 = SKP_SMLAWB( SKP_FIX_CONST( 1.0, 24 ), coefs_syn_Q24[ 0 ], lambda_Q16 );
gain_syn_Q16 = SKP_DIV32_varQ( nom_Q16, den_Q24, 24 );
den_Q24 = SKP_SMLAWB( SKP_FIX_CONST( 1.0, 24 ), coefs_ana_Q24[ 0 ], lambda_Q16 );
gain_ana_Q16 = SKP_DIV32_varQ( nom_Q16, den_Q24, 24 );
for( i = 0; i < order; i++ ) {
coefs_syn_Q24[ i ] = SKP_SMULWW( gain_syn_Q16, coefs_syn_Q24[ i ] );
coefs_ana_Q24[ i ] = SKP_SMULWW( gain_ana_Q16, coefs_ana_Q24[ i ] );
}
}
SKP_assert( 0 );
}
/* Control internal sampling rate */
SKP_int SKP_Silk_control_audio_bandwidth(
SKP_Silk_encoder_state *psEncC, /* I/O Pointer to Silk encoder state */
SKP_int32 TargetRate_bps /* I Target max bitrate (bps) */
)
{
SKP_int fs_kHz;
fs_kHz = psEncC->fs_kHz;
/* Reduce bitrate for 10 ms modes in these calculations */
if( psEncC->nb_subfr == 2 ) {
TargetRate_bps -= REDUCE_BITRATE_10_MS_BPS;
}
if( fs_kHz == 0 ) {
/* Encoder has just been initialized */
if( TargetRate_bps >= WB2MB_BITRATE_BPS ) {
fs_kHz = 16;
} else if( TargetRate_bps >= MB2NB_BITRATE_BPS ) {
fs_kHz = 12;
} else {
fs_kHz = 8;
}
/* Make sure internal rate is not higher than external rate or maximum allowed, or lower than minimum allowed */
fs_kHz = SKP_min( fs_kHz, SKP_DIV32_16( psEncC->API_fs_Hz, 1000 ) );
fs_kHz = SKP_min( fs_kHz, psEncC->maxInternal_fs_kHz );
fs_kHz = SKP_max( fs_kHz, psEncC->minInternal_fs_kHz );
} else if( SKP_SMULBB( fs_kHz, 1000 ) > psEncC->API_fs_Hz || fs_kHz > psEncC->maxInternal_fs_kHz || fs_kHz < psEncC->minInternal_fs_kHz ) {
/* Make sure internal rate is not higher than external rate or maximum allowed, or lower than minimum allowed */
fs_kHz = SKP_DIV32_16( psEncC->API_fs_Hz, 1000 );
fs_kHz = SKP_min( fs_kHz, psEncC->maxInternal_fs_kHz );
fs_kHz = SKP_max( fs_kHz, psEncC->minInternal_fs_kHz );
} else {
/* State machine for the internal sampling rate switching */
if( psEncC->API_fs_Hz > 8000 && psEncC->prevSignalType == TYPE_NO_VOICE_ACTIVITY ) { /* Low speech activity */
/* Check if we should switch down */
if( ( psEncC->fs_kHz == 12 && TargetRate_bps < MB2NB_BITRATE_BPS && psEncC->minInternal_fs_kHz <= 8 ) ||
( psEncC->fs_kHz == 16 && TargetRate_bps < WB2MB_BITRATE_BPS && psEncC->minInternal_fs_kHz <= 12 ) )
{
/* Switch down */
if( SWITCH_TRANSITION_FILTERING && psEncC->sLP.mode == 0 ) {
/* New transition */
psEncC->sLP.transition_frame_no = TRANSITION_FRAMES;
/* Reset transition filter state */
SKP_memset( psEncC->sLP.In_LP_State, 0, sizeof( psEncC->sLP.In_LP_State ) );
}
if( psEncC->sLP.transition_frame_no <= 0 ) {
/* Stop transition phase */
psEncC->sLP.mode = 0;
/* Switch to a lower sample frequency */
fs_kHz = psEncC->fs_kHz == 16 ? 12 : 8;
} else {
/* Direction: down (at double speed) */
psEncC->sLP.mode = -2;
}
}
else
if( ( psEncC->fs_kHz == 8 && TargetRate_bps > NB2MB_BITRATE_BPS && psEncC->maxInternal_fs_kHz >= 12 && psEncC->API_fs_Hz >= 12000 ) ||
( psEncC->fs_kHz == 12 && TargetRate_bps > MB2WB_BITRATE_BPS && psEncC->maxInternal_fs_kHz >= 16 && psEncC->API_fs_Hz >= 16000 ) )
{
/* Switch up */
if( SWITCH_TRANSITION_FILTERING && psEncC->sLP.mode == 0 ) {
/* Switch to a higher sample frequency */
fs_kHz = psEncC->fs_kHz == 8 ? 12 : 16;
/* New transition */
psEncC->sLP.transition_frame_no = 0;
}
if( psEncC->sLP.transition_frame_no >= TRANSITION_FRAMES ) {
/* Stop transition phase */
psEncC->sLP.mode = 0;
} else {
/* Direction: up */
psEncC->sLP.mode = 1;
}
}
}
}
#ifdef FORCE_INTERNAL_FS_KHZ
fs_kHz = FORCE_INTERNAL_FS_KHZ;
#endif
return fs_kHz;
}
void SKP_Silk_find_pred_coefs_FIX(
SKP_Silk_encoder_state_FIX *psEnc, /* I/O encoder state */
SKP_Silk_encoder_control_FIX *psEncCtrl, /* I/O encoder control */
const SKP_int16 res_pitch[], /* I Residual from pitch analysis */
const SKP_int16 x[] /* I Speech signal */
)
{
SKP_int i;
SKP_int32 WLTP[ MAX_NB_SUBFR * LTP_ORDER * LTP_ORDER ];
SKP_int32 invGains_Q16[ MAX_NB_SUBFR ], local_gains[ MAX_NB_SUBFR ], Wght_Q15[ MAX_NB_SUBFR ];
SKP_int16 NLSF_Q15[ MAX_LPC_ORDER ];
const SKP_int16 *x_ptr;
SKP_int16 *x_pre_ptr, LPC_in_pre[ MAX_NB_SUBFR * MAX_LPC_ORDER + MAX_FRAME_LENGTH ];
SKP_int32 tmp, min_gain_Q16;
SKP_int LTP_corrs_rshift[ MAX_NB_SUBFR ];
/* weighting for weighted least squares */
min_gain_Q16 = SKP_int32_MAX >> 6;
for( i = 0; i < psEnc->sCmn.nb_subfr; i++ ) {
min_gain_Q16 = SKP_min( min_gain_Q16, psEncCtrl->Gains_Q16[ i ] );
}
for( i = 0; i < psEnc->sCmn.nb_subfr; i++ ) {
/* Divide to Q16 */
SKP_assert( psEncCtrl->Gains_Q16[ i ] > 0 );
/* Invert and normalize gains, and ensure that maximum invGains_Q16 is within range of a 16 bit int */
invGains_Q16[ i ] = SKP_DIV32_varQ( min_gain_Q16, psEncCtrl->Gains_Q16[ i ], 16 - 2 );
/* Ensure Wght_Q15 a minimum value 1 */
invGains_Q16[ i ] = SKP_max( invGains_Q16[ i ], 363 );
/* Square the inverted gains */
SKP_assert( invGains_Q16[ i ] == SKP_SAT16( invGains_Q16[ i ] ) );
tmp = SKP_SMULWB( invGains_Q16[ i ], invGains_Q16[ i ] );
Wght_Q15[ i ] = SKP_RSHIFT( tmp, 1 );
/* Invert the inverted and normalized gains */
local_gains[ i ] = SKP_DIV32( ( 1 << 16 ), invGains_Q16[ i ] );
}
if( psEnc->sCmn.indices.signalType == TYPE_VOICED ) {
/**********/
/* VOICED */
/**********/
SKP_assert( psEnc->sCmn.ltp_mem_length - psEnc->sCmn.predictLPCOrder >= psEncCtrl->pitchL[ 0 ] + LTP_ORDER / 2 );
/* LTP analysis */
SKP_Silk_find_LTP_FIX( psEncCtrl->LTPCoef_Q14, WLTP, &psEncCtrl->LTPredCodGain_Q7,
res_pitch, psEncCtrl->pitchL, Wght_Q15, psEnc->sCmn.subfr_length,
psEnc->sCmn.nb_subfr, psEnc->sCmn.ltp_mem_length, LTP_corrs_rshift );
/* Quantize LTP gain parameters */
SKP_Silk_quant_LTP_gains( psEncCtrl->LTPCoef_Q14, psEnc->sCmn.indices.LTPIndex, &psEnc->sCmn.indices.PERIndex,
WLTP, psEnc->sCmn.mu_LTP_Q9, psEnc->sCmn.LTPQuantLowComplexity, psEnc->sCmn.nb_subfr);
/* Control LTP scaling */
SKP_Silk_LTP_scale_ctrl_FIX( psEnc, psEncCtrl );
/* Create LTP residual */
SKP_Silk_LTP_analysis_filter_FIX( LPC_in_pre, psEnc->x_buf + psEnc->sCmn.ltp_mem_length - psEnc->sCmn.predictLPCOrder,
psEncCtrl->LTPCoef_Q14, psEncCtrl->pitchL, invGains_Q16, psEnc->sCmn.subfr_length, psEnc->sCmn.nb_subfr, psEnc->sCmn.predictLPCOrder );
} else {
/************/
/* UNVOICED */
/************/
/* Create signal with prepended subframes, scaled by inverse gains */
x_ptr = x - psEnc->sCmn.predictLPCOrder;
x_pre_ptr = LPC_in_pre;
for( i = 0; i < psEnc->sCmn.nb_subfr; i++ ) {
SKP_Silk_scale_copy_vector16( x_pre_ptr, x_ptr, invGains_Q16[ i ],
psEnc->sCmn.subfr_length + psEnc->sCmn.predictLPCOrder );
x_pre_ptr += psEnc->sCmn.subfr_length + psEnc->sCmn.predictLPCOrder;
x_ptr += psEnc->sCmn.subfr_length;
}
SKP_memset( psEncCtrl->LTPCoef_Q14, 0, psEnc->sCmn.nb_subfr * LTP_ORDER * sizeof( SKP_int16 ) );
psEncCtrl->LTPredCodGain_Q7 = 0;
}
/* LPC_in_pre contains the LTP-filtered input for voiced, and the unfiltered input for unvoiced */
TIC(FIND_LPC)
SKP_Silk_find_LPC_FIX( NLSF_Q15, &psEnc->sCmn.indices.NLSFInterpCoef_Q2, psEnc->sCmn.prev_NLSFq_Q15,
psEnc->sCmn.useInterpolatedNLSFs, psEnc->sCmn.first_frame_after_reset, psEnc->sCmn.predictLPCOrder,
LPC_in_pre, psEnc->sCmn.subfr_length + psEnc->sCmn.predictLPCOrder, psEnc->sCmn.nb_subfr );
TOC(FIND_LPC)
/* Quantize LSFs */
TIC(PROCESS_LSFS)
SKP_Silk_process_NLSFs( &psEnc->sCmn, psEncCtrl->PredCoef_Q12, NLSF_Q15, psEnc->sCmn.prev_NLSFq_Q15 );
TOC(PROCESS_LSFS)
/* Calculate residual energy using quantized LPC coefficients */
SKP_Silk_residual_energy_FIX( psEncCtrl->ResNrg, psEncCtrl->ResNrgQ, LPC_in_pre, psEncCtrl->PredCoef_Q12, local_gains,
psEnc->sCmn.subfr_length, psEnc->sCmn.nb_subfr, psEnc->sCmn.predictLPCOrder );
/* Copy to prediction struct for use in next frame for fluctuation reduction */
SKP_memcpy( psEnc->sCmn.prev_NLSFq_Q15, NLSF_Q15, sizeof( psEnc->sCmn.prev_NLSFq_Q15 ) );
}
/* Calculates correlation matrix X'*X */
void SKP_Silk_corrMatrix_FIX(
const SKP_int16 *x, /* I x vector [L + order - 1] used to form data matrix X */
const SKP_int L, /* I Length of vectors */
const SKP_int order, /* I Max lag for correlation */
const SKP_int head_room, /* I Desired headroom */
SKP_int32 *XX, /* O Pointer to X'*X correlation matrix [ order x order ]*/
SKP_int *rshifts /* I/O Right shifts of correlations */
)
{
SKP_int i, j, lag, rshifts_local, head_room_rshifts;
SKP_int32 energy;
const SKP_int16 *ptr1, *ptr2;
/* Calculate energy to find shift used to fit in 32 bits */
SKP_Silk_sum_sqr_shift( &energy, &rshifts_local, x, L + order - 1 );
/* Add shifts to get the desired head room */
head_room_rshifts = SKP_max( head_room - SKP_Silk_CLZ32( energy ), 0 );
energy = SKP_RSHIFT32( energy, head_room_rshifts );
rshifts_local += head_room_rshifts;
/* Calculate energy of first column (0) of X: X[:,0]'*X[:,0] */
/* Remove contribution of first order - 1 samples */
for( i = 0; i < order - 1; i++ ) {
energy -= SKP_RSHIFT32( SKP_SMULBB( x[ i ], x[ i ] ), rshifts_local );
}
if( rshifts_local < *rshifts ) {
/* Adjust energy */
energy = SKP_RSHIFT32( energy, *rshifts - rshifts_local );
rshifts_local = *rshifts;
}
/* Calculate energy of remaining columns of X: X[:,j]'*X[:,j] */
/* Fill out the diagonal of the correlation matrix */
matrix_ptr( XX, 0, 0, order ) = energy;
ptr1 = &x[ order - 1 ]; /* First sample of column 0 of X */
for( j = 1; j < order; j++ ) {
energy = SKP_SUB32( energy, SKP_RSHIFT32( SKP_SMULBB( ptr1[ L - j ], ptr1[ L - j ] ), rshifts_local ) );
energy = SKP_ADD32( energy, SKP_RSHIFT32( SKP_SMULBB( ptr1[ -j ], ptr1[ -j ] ), rshifts_local ) );
matrix_ptr( XX, j, j, order ) = energy;
}
ptr2 = &x[ order - 2 ]; /* First sample of column 1 of X */
/* Calculate the remaining elements of the correlation matrix */
if( rshifts_local > 0 ) {
/* Right shifting used */
for( lag = 1; lag < order; lag++ ) {
/* Inner product of column 0 and column lag: X[:,0]'*X[:,lag] */
energy = 0;
for( i = 0; i < L; i++ ) {
energy += SKP_RSHIFT32( SKP_SMULBB( ptr1[ i ], ptr2[i] ), rshifts_local );
}
/* Calculate remaining off diagonal: X[:,j]'*X[:,j + lag] */
matrix_ptr( XX, lag, 0, order ) = energy;
matrix_ptr( XX, 0, lag, order ) = energy;
for( j = 1; j < ( order - lag ); j++ ) {
energy = SKP_SUB32( energy, SKP_RSHIFT32( SKP_SMULBB( ptr1[ L - j ], ptr2[ L - j ] ), rshifts_local ) );
energy = SKP_ADD32( energy, SKP_RSHIFT32( SKP_SMULBB( ptr1[ -j ], ptr2[ -j ] ), rshifts_local ) );
matrix_ptr( XX, lag + j, j, order ) = energy;
matrix_ptr( XX, j, lag + j, order ) = energy;
}
ptr2--; /* Update pointer to first sample of next column (lag) in X */
}
} else {
for( lag = 1; lag < order; lag++ ) {
/* Inner product of column 0 and column lag: X[:,0]'*X[:,lag] */
energy = SKP_Silk_inner_prod_aligned( ptr1, ptr2, L );
matrix_ptr( XX, lag, 0, order ) = energy;
matrix_ptr( XX, 0, lag, order ) = energy;
/* Calculate remaining off diagonal: X[:,j]'*X[:,j + lag] */
for( j = 1; j < ( order - lag ); j++ ) {
energy = SKP_SUB32( energy, SKP_SMULBB( ptr1[ L - j ], ptr2[ L - j ] ) );
energy = SKP_SMLABB( energy, ptr1[ -j ], ptr2[ -j ] );
matrix_ptr( XX, lag + j, j, order ) = energy;
matrix_ptr( XX, j, lag + j, order ) = energy;
}
ptr2--;/* Update pointer to first sample of next column (lag) in X */
}
}
*rshifts = rshifts_local;
}
/* amplitude of monic warped coefficients by using bandwidth expansion on the true coefficients */
SKP_INLINE void warped_true2monic_coefs(
SKP_float *coefs_syn,
SKP_float *coefs_ana,
SKP_float lambda,
SKP_float limit,
SKP_int order
) {
SKP_int i, iter, ind = 0;
SKP_float tmp, maxabs, chirp, gain_syn, gain_ana;
/* Convert to monic coefficients */
for( i = order - 1; i > 0; i-- ) {
coefs_syn[ i - 1 ] -= lambda * coefs_syn[ i ];
coefs_ana[ i - 1 ] -= lambda * coefs_ana[ i ];
}
gain_syn = ( 1.0f - lambda * lambda ) / ( 1.0f + lambda * coefs_syn[ 0 ] );
gain_ana = ( 1.0f - lambda * lambda ) / ( 1.0f + lambda * coefs_ana[ 0 ] );
for( i = 0; i < order; i++ ) {
coefs_syn[ i ] *= gain_syn;
coefs_ana[ i ] *= gain_ana;
}
/* Limit */
for( iter = 0; iter < 10; iter++ ) {
/* Find maximum absolute value */
maxabs = -1.0f;
for( i = 0; i < order; i++ ) {
tmp = SKP_max( SKP_abs_float( coefs_syn[ i ] ), SKP_abs_float( coefs_ana[ i ] ) );
if( tmp > maxabs ) {
maxabs = tmp;
ind = i;
}
}
if( maxabs <= limit ) {
/* Coefficients are within range - done */
return;
}
/* Convert back to true warped coefficients */
for( i = 1; i < order; i++ ) {
coefs_syn[ i - 1 ] += lambda * coefs_syn[ i ];
coefs_ana[ i - 1 ] += lambda * coefs_ana[ i ];
}
gain_syn = 1.0f / gain_syn;
gain_ana = 1.0f / gain_ana;
for( i = 0; i < order; i++ ) {
coefs_syn[ i ] *= gain_syn;
coefs_ana[ i ] *= gain_ana;
}
/* Apply bandwidth expansion */
chirp = 0.99f - ( 0.8f + 0.1f * iter ) * ( maxabs - limit ) / ( maxabs * ( ind + 1 ) );
silk_bwexpander_FLP( coefs_syn, order, chirp );
silk_bwexpander_FLP( coefs_ana, order, chirp );
/* Convert to monic warped coefficients */
for( i = order - 1; i > 0; i-- ) {
coefs_syn[ i - 1 ] -= lambda * coefs_syn[ i ];
coefs_ana[ i - 1 ] -= lambda * coefs_ana[ i ];
}
gain_syn = ( 1.0f - lambda * lambda ) / ( 1.0f + lambda * coefs_syn[ 0 ] );
gain_ana = ( 1.0f - lambda * lambda ) / ( 1.0f + lambda * coefs_ana[ 0 ] );
for( i = 0; i < order; i++ ) {
coefs_syn[ i ] *= gain_syn;
coefs_ana[ i ] *= gain_ana;
}
}
SKP_assert( 0 );
}
void SKP_Silk_PLC_update(
SKP_Silk_decoder_state *psDec, /* (I/O) Decoder state */
SKP_Silk_decoder_control *psDecCtrl, /* (I/O) Decoder control */
SKP_int16 signal[],
SKP_int length
)
{
SKP_int32 LTP_Gain_Q14, temp_LTP_Gain_Q14;
SKP_int i, j;
SKP_Silk_PLC_struct *psPLC;
psPLC = &psDec->sPLC;
/* Update parameters used in case of packet loss */
psDec->prev_sigtype = psDecCtrl->sigtype;
LTP_Gain_Q14 = 0;
if( psDecCtrl->sigtype == SIG_TYPE_VOICED ) {
/* Find the parameters for the last subframe which contains a pitch pulse */
for( j = 0; j * psDec->subfr_length < psDecCtrl->pitchL[ NB_SUBFR - 1 ]; j++ ) {
temp_LTP_Gain_Q14 = 0;
for( i = 0; i < LTP_ORDER; i++ ) {
temp_LTP_Gain_Q14 += psDecCtrl->LTPCoef_Q14[ ( NB_SUBFR - 1 - j ) * LTP_ORDER + i ];
}
if( temp_LTP_Gain_Q14 > LTP_Gain_Q14 ) {
LTP_Gain_Q14 = temp_LTP_Gain_Q14;
SKP_memcpy( psPLC->LTPCoef_Q14,
&psDecCtrl->LTPCoef_Q14[ SKP_SMULBB( NB_SUBFR - 1 - j, LTP_ORDER ) ],
LTP_ORDER * sizeof( SKP_int16 ) );
psPLC->pitchL_Q8 = SKP_LSHIFT( psDecCtrl->pitchL[ NB_SUBFR - 1 - j ], 8 );
}
}
#if USE_SINGLE_TAP
SKP_memset( psPLC->LTPCoef_Q14, 0, LTP_ORDER * sizeof( SKP_int16 ) );
psPLC->LTPCoef_Q14[ LTP_ORDER / 2 ] = LTP_Gain_Q14;
#endif
/* Limit LT coefs */
if( LTP_Gain_Q14 < V_PITCH_GAIN_START_MIN_Q14 ) {
SKP_int scale_Q10;
SKP_int32 tmp;
tmp = SKP_LSHIFT( V_PITCH_GAIN_START_MIN_Q14, 10 );
scale_Q10 = SKP_DIV32( tmp, SKP_max( LTP_Gain_Q14, 1 ) );
for( i = 0; i < LTP_ORDER; i++ ) {
psPLC->LTPCoef_Q14[ i ] = SKP_RSHIFT( SKP_SMULBB( psPLC->LTPCoef_Q14[ i ], scale_Q10 ), 10 );
}
} else if( LTP_Gain_Q14 > V_PITCH_GAIN_START_MAX_Q14 ) {
SKP_int scale_Q14;
SKP_int32 tmp;
tmp = SKP_LSHIFT( V_PITCH_GAIN_START_MAX_Q14, 14 );
scale_Q14 = SKP_DIV32( tmp, SKP_max( LTP_Gain_Q14, 1 ) );
for( i = 0; i < LTP_ORDER; i++ ) {
psPLC->LTPCoef_Q14[ i ] = SKP_RSHIFT( SKP_SMULBB( psPLC->LTPCoef_Q14[ i ], scale_Q14 ), 14 );
}
}
} else {
psPLC->pitchL_Q8 = SKP_LSHIFT( SKP_SMULBB( psDec->fs_kHz, 18 ), 8 );
SKP_memset( psPLC->LTPCoef_Q14, 0, LTP_ORDER * sizeof( SKP_int16 ));
}
/* Save LPC coeficients */
SKP_memcpy( psPLC->prevLPC_Q12, psDecCtrl->PredCoef_Q12[ 1 ], psDec->LPC_order * sizeof( SKP_int16 ) );
psPLC->prevLTP_scale_Q14 = psDecCtrl->LTP_scale_Q14;
/* Save Gains */
SKP_memcpy( psPLC->prevGain_Q16, psDecCtrl->Gains_Q16, NB_SUBFR * sizeof( SKP_int32 ) );
}
/* Compute reflection coefficients from input signal */
void SKP_Silk_burg_modified(
SKP_int32 *res_nrg, /* O residual energy */
SKP_int *res_nrg_Q, /* O residual energy Q value */
SKP_int32 A_Q16[], /* O prediction coefficients (length order) */
const SKP_int16 x[], /* I input signal, length: nb_subfr * ( D + subfr_length ) */
const SKP_int subfr_length, /* I input signal subframe length (including D preceeding samples) */
const SKP_int nb_subfr, /* I number of subframes stacked in x */
const SKP_int32 WhiteNoiseFrac_Q32, /* I fraction added to zero-lag autocorrelation */
const SKP_int D /* I order */
)
{
SKP_int k, n, s, lz, rshifts, rshifts_extra;
SKP_int32 C0, num, nrg, rc_Q31, Atmp_QA, Atmp1, tmp1, tmp2, x1, x2;
const SKP_int16 *x_ptr;
SKP_int32 C_first_row[ SKP_Silk_MAX_ORDER_LPC ];
SKP_int32 C_last_row[ SKP_Silk_MAX_ORDER_LPC ];
SKP_int32 Af_QA[ SKP_Silk_MAX_ORDER_LPC ];
SKP_int32 CAf[ SKP_Silk_MAX_ORDER_LPC + 1 ];
SKP_int32 CAb[ SKP_Silk_MAX_ORDER_LPC + 1 ];
SKP_assert( subfr_length * nb_subfr <= MAX_FRAME_SIZE );
SKP_assert( nb_subfr <= MAX_NB_SUBFR );
/* Compute autocorrelations, added over subframes */
SKP_Silk_sum_sqr_shift( &C0, &rshifts, x, nb_subfr * subfr_length );
if( rshifts > MAX_RSHIFTS ) {
C0 = SKP_LSHIFT32( C0, rshifts - MAX_RSHIFTS );
SKP_assert( C0 > 0 );
rshifts = MAX_RSHIFTS;
} else {
lz = SKP_Silk_CLZ32( C0 ) - 1;
rshifts_extra = N_BITS_HEAD_ROOM - lz;
if( rshifts_extra > 0 ) {
rshifts_extra = SKP_min( rshifts_extra, MAX_RSHIFTS - rshifts );
C0 = SKP_RSHIFT32( C0, rshifts_extra );
} else {
rshifts_extra = SKP_max( rshifts_extra, MIN_RSHIFTS - rshifts );
C0 = SKP_LSHIFT32( C0, -rshifts_extra );
}
rshifts += rshifts_extra;
}
SKP_memset( C_first_row, 0, SKP_Silk_MAX_ORDER_LPC * sizeof( SKP_int32 ) );
if( rshifts > 0 ) {
for( s = 0; s < nb_subfr; s++ ) {
x_ptr = x + s * subfr_length;
for( n = 1; n < D + 1; n++ ) {
C_first_row[ n - 1 ] += (SKP_int32)SKP_RSHIFT64(
SKP_Silk_inner_prod16_aligned_64( x_ptr, x_ptr + n, subfr_length - n ), rshifts );
}
}
} else {
for( s = 0; s < nb_subfr; s++ ) {
x_ptr = x + s * subfr_length;
for( n = 1; n < D + 1; n++ ) {
C_first_row[ n - 1 ] += SKP_LSHIFT32(
SKP_Silk_inner_prod_aligned( x_ptr, x_ptr + n, subfr_length - n ), -rshifts );
}
}
}
SKP_memcpy( C_last_row, C_first_row, SKP_Silk_MAX_ORDER_LPC * sizeof( SKP_int32 ) );
/* Initialize */
CAb[ 0 ] = CAf[ 0 ] = C0 + SKP_SMMUL( WhiteNoiseFrac_Q32, C0 ) + 1; // Q(-rshifts)
for( n = 0; n < D; n++ ) {
/* Update first row of correlation matrix (without first element) */
/* Update last row of correlation matrix (without last element, stored in reversed order) */
/* Update C * Af */
/* Update C * flipud(Af) (stored in reversed order) */
if( rshifts > -2 ) {
for( s = 0; s < nb_subfr; s++ ) {
x_ptr = x + s * subfr_length;
x1 = -SKP_LSHIFT32( (SKP_int32)x_ptr[ n ], 16 - rshifts ); // Q(16-rshifts)
x2 = -SKP_LSHIFT32( (SKP_int32)x_ptr[ subfr_length - n - 1 ], 16 - rshifts ); // Q(16-rshifts)
tmp1 = SKP_LSHIFT32( (SKP_int32)x_ptr[ n ], QA - 16 ); // Q(QA-16)
tmp2 = SKP_LSHIFT32( (SKP_int32)x_ptr[ subfr_length - n - 1 ], QA - 16 ); // Q(QA-16)
for( k = 0; k < n; k++ ) {
C_first_row[ k ] = SKP_SMLAWB( C_first_row[ k ], x1, x_ptr[ n - k - 1 ] ); // Q( -rshifts )
C_last_row[ k ] = SKP_SMLAWB( C_last_row[ k ], x2, x_ptr[ subfr_length - n + k ] ); // Q( -rshifts )
Atmp_QA = Af_QA[ k ];
tmp1 = SKP_SMLAWB( tmp1, Atmp_QA, x_ptr[ n - k - 1 ] ); // Q(QA-16)
tmp2 = SKP_SMLAWB( tmp2, Atmp_QA, x_ptr[ subfr_length - n + k ] ); // Q(QA-16)
}
tmp1 = SKP_LSHIFT32( -tmp1, 32 - QA - rshifts ); // Q(16-rshifts)
tmp2 = SKP_LSHIFT32( -tmp2, 32 - QA - rshifts ); // Q(16-rshifts)
for( k = 0; k <= n; k++ ) {
CAf[ k ] = SKP_SMLAWB( CAf[ k ], tmp1, x_ptr[ n - k ] ); // Q( -rshift )
CAb[ k ] = SKP_SMLAWB( CAb[ k ], tmp2, x_ptr[ subfr_length - n + k - 1 ] ); // Q( -rshift )
}
}
} else {
for( s = 0; s < nb_subfr; s++ ) {
x_ptr = x + s * subfr_length;
x1 = -SKP_LSHIFT32( (SKP_int32)x_ptr[ n ], -rshifts ); // Q( -rshifts )
x2 = -SKP_LSHIFT32( (SKP_int32)x_ptr[ subfr_length - n - 1 ], -rshifts ); // Q( -rshifts )
tmp1 = SKP_LSHIFT32( (SKP_int32)x_ptr[ n ], 17 ); // Q17
tmp2 = SKP_LSHIFT32( (SKP_int32)x_ptr[ subfr_length - n - 1 ], 17 ); // Q17
for( k = 0; k < n; k++ ) {
C_first_row[ k ] = SKP_MLA( C_first_row[ k ], x1, x_ptr[ n - k - 1 ] ); // Q( -rshifts )
C_last_row[ k ] = SKP_MLA( C_last_row[ k ], x2, x_ptr[ subfr_length - n + k ] ); // Q( -rshifts )
Atmp1 = SKP_RSHIFT_ROUND( Af_QA[ k ], QA - 17 ); // Q17
tmp1 = SKP_MLA( tmp1, x_ptr[ n - k - 1 ], Atmp1 ); // Q17
tmp2 = SKP_MLA( tmp2, x_ptr[ subfr_length - n + k ], Atmp1 ); // Q17
}
tmp1 = -tmp1; // Q17
tmp2 = -tmp2; // Q17
for( k = 0; k <= n; k++ ) {
CAf[ k ] = SKP_SMLAWW( CAf[ k ], tmp1,
SKP_LSHIFT32( (SKP_int32)x_ptr[ n - k ], -rshifts - 1 ) ); // Q( -rshift )
CAb[ k ] = SKP_SMLAWW( CAb[ k ], tmp2,
SKP_LSHIFT32( (SKP_int32)x_ptr[ subfr_length - n + k - 1 ], -rshifts - 1 ) );// Q( -rshift )
}
}
}
/* Calculate nominator and denominator for the next order reflection (parcor) coefficient */
tmp1 = C_first_row[ n ]; // Q( -rshifts )
tmp2 = C_last_row[ n ]; // Q( -rshifts )
num = 0; // Q( -rshifts )
nrg = SKP_ADD32( CAb[ 0 ], CAf[ 0 ] ); // Q( 1-rshifts )
for( k = 0; k < n; k++ ) {
Atmp_QA = Af_QA[ k ];
lz = SKP_Silk_CLZ32( SKP_abs( Atmp_QA ) ) - 1;
lz = SKP_min( 32 - QA, lz );
Atmp1 = SKP_LSHIFT32( Atmp_QA, lz ); // Q( QA + lz )
tmp1 = SKP_ADD_LSHIFT32( tmp1, SKP_SMMUL( C_last_row[ n - k - 1 ], Atmp1 ), 32 - QA - lz ); // Q( -rshifts )
tmp2 = SKP_ADD_LSHIFT32( tmp2, SKP_SMMUL( C_first_row[ n - k - 1 ], Atmp1 ), 32 - QA - lz ); // Q( -rshifts )
num = SKP_ADD_LSHIFT32( num, SKP_SMMUL( CAb[ n - k ], Atmp1 ), 32 - QA - lz ); // Q( -rshifts )
nrg = SKP_ADD_LSHIFT32( nrg, SKP_SMMUL( SKP_ADD32( CAb[ k + 1 ], CAf[ k + 1 ] ),
Atmp1 ), 32 - QA - lz ); // Q( 1-rshifts )
}
CAf[ n + 1 ] = tmp1; // Q( -rshifts )
CAb[ n + 1 ] = tmp2; // Q( -rshifts )
num = SKP_ADD32( num, tmp2 ); // Q( -rshifts )
num = SKP_LSHIFT32( -num, 1 ); // Q( 1-rshifts )
/* Calculate the next order reflection (parcor) coefficient */
if( SKP_abs( num ) < nrg ) {
rc_Q31 = SKP_DIV32_varQ( num, nrg, 31 );
} else {
/* Negative energy or ratio too high; set remaining coefficients to zero and exit loop */
SKP_memset( &Af_QA[ n ], 0, ( D - n ) * sizeof( SKP_int32 ) );
SKP_assert( 0 );
break;
}
/* Update the AR coefficients */
for( k = 0; k < (n + 1) >> 1; k++ ) {
tmp1 = Af_QA[ k ]; // QA
tmp2 = Af_QA[ n - k - 1 ]; // QA
Af_QA[ k ] = SKP_ADD_LSHIFT32( tmp1, SKP_SMMUL( tmp2, rc_Q31 ), 1 ); // QA
Af_QA[ n - k - 1 ] = SKP_ADD_LSHIFT32( tmp2, SKP_SMMUL( tmp1, rc_Q31 ), 1 ); // QA
}
Af_QA[ n ] = SKP_RSHIFT32( rc_Q31, 31 - QA ); // QA
/* Update C * Af and C * Ab */
for( k = 0; k <= n + 1; k++ ) {
tmp1 = CAf[ k ]; // Q( -rshifts )
tmp2 = CAb[ n - k + 1 ]; // Q( -rshifts )
CAf[ k ] = SKP_ADD_LSHIFT32( tmp1, SKP_SMMUL( tmp2, rc_Q31 ), 1 ); // Q( -rshifts )
CAb[ n - k + 1 ] = SKP_ADD_LSHIFT32( tmp2, SKP_SMMUL( tmp1, rc_Q31 ), 1 ); // Q( -rshifts )
}
}
/* Return residual energy */
nrg = CAf[ 0 ]; // Q( -rshifts )
tmp1 = 1 << 16; // Q16
for( k = 0; k < D; k++ ) {
Atmp1 = SKP_RSHIFT_ROUND( Af_QA[ k ], QA - 16 ); // Q16
nrg = SKP_SMLAWW( nrg, CAf[ k + 1 ], Atmp1 ); // Q( -rshifts )
tmp1 = SKP_SMLAWW( tmp1, Atmp1, Atmp1 ); // Q16
A_Q16[ k ] = -Atmp1;
}
*res_nrg = SKP_SMLAWW( nrg, SKP_SMMUL( WhiteNoiseFrac_Q32, C0 ), -tmp1 ); // Q( -rshifts )
*res_nrg_Q = -rshifts;
}
void SKP_Silk_find_pred_coefs_FIX(SKP_Silk_encoder_state_FIX * psEnc, /* I/O encoder state */
SKP_Silk_encoder_control_FIX * psEncCtrl, /* I/O encoder control */
const int16_t res_pitch[] /* I Residual from pitch analysis */
)
{
int i;
int32_t WLTP[NB_SUBFR * LTP_ORDER * LTP_ORDER];
int32_t invGains_Q16[NB_SUBFR], local_gains_Qx[NB_SUBFR],
Wght_Q15[NB_SUBFR];
int NLSF_Q15[MAX_LPC_ORDER];
const int16_t *x_ptr;
int16_t *x_pre_ptr,
LPC_in_pre[NB_SUBFR * MAX_LPC_ORDER + MAX_FRAME_LENGTH];
int32_t tmp, min_gain_Q16;
#if !VARQ
int LZ;
#endif
int LTP_corrs_rshift[NB_SUBFR];
/* weighting for weighted least squares */
min_gain_Q16 = int32_t_MAX >> 6;
for (i = 0; i < NB_SUBFR; i++) {
min_gain_Q16 = SKP_min(min_gain_Q16, psEncCtrl->Gains_Q16[i]);
}
#if !VARQ
LZ = SKP_Silk_CLZ32(min_gain_Q16) - 1;
LZ = SKP_LIMIT(LZ, 0, 16);
min_gain_Q16 = SKP_RSHIFT(min_gain_Q16, 2); /* Ensure that maximum invGains_Q16 is within range of a 16 bit int */
#endif
for (i = 0; i < NB_SUBFR; i++) {
/* Divide to Q16 */
assert(psEncCtrl->Gains_Q16[i] > 0);
#if VARQ
/* Invert and normalize gains, and ensure that maximum invGains_Q16 is within range of a 16 bit int */
invGains_Q16[i] =
SKP_DIV32_varQ(min_gain_Q16, psEncCtrl->Gains_Q16[i],
16 - 2);
#else
invGains_Q16[i] =
SKP_DIV32(SKP_LSHIFT(min_gain_Q16, LZ),
SKP_RSHIFT(psEncCtrl->Gains_Q16[i], 16 - LZ));
#endif
/* Ensure Wght_Q15 a minimum value 1 */
invGains_Q16[i] = SKP_max(invGains_Q16[i], 363);
/* Square the inverted gains */
assert(invGains_Q16[i] == SKP_SAT16(invGains_Q16[i]));
tmp = SKP_SMULWB(invGains_Q16[i], invGains_Q16[i]);
Wght_Q15[i] = SKP_RSHIFT(tmp, 1);
/* Invert the inverted and normalized gains */
local_gains_Qx[i] =
SKP_DIV32((1 << (16 + Qx)), invGains_Q16[i]);
}
if (psEncCtrl->sCmn.sigtype == SIG_TYPE_VOICED) {
/**********/
/* VOICED */
/**********/
assert(psEnc->sCmn.frame_length -
psEnc->sCmn.predictLPCOrder >=
psEncCtrl->sCmn.pitchL[0] + LTP_ORDER / 2);
/* LTP analysis */
SKP_Silk_find_LTP_FIX(psEncCtrl->LTPCoef_Q14, WLTP,
&psEncCtrl->LTPredCodGain_Q7, res_pitch,
res_pitch +
SKP_RSHIFT(psEnc->sCmn.frame_length, 1),
psEncCtrl->sCmn.pitchL, Wght_Q15,
psEnc->sCmn.subfr_length,
psEnc->sCmn.frame_length,
LTP_corrs_rshift);
/* Quantize LTP gain parameters */
SKP_Silk_quant_LTP_gains_FIX(psEncCtrl->LTPCoef_Q14,
psEncCtrl->sCmn.LTPIndex,
&psEncCtrl->sCmn.PERIndex, WLTP,
psEnc->mu_LTP_Q8,
psEnc->sCmn.LTPQuantLowComplexity);
/* Control LTP scaling */
SKP_Silk_LTP_scale_ctrl_FIX(psEnc, psEncCtrl);
/* Create LTP residual */
SKP_Silk_LTP_analysis_filter_FIX(LPC_in_pre,
psEnc->x_buf +
psEnc->sCmn.frame_length -
psEnc->sCmn.predictLPCOrder,
psEncCtrl->LTPCoef_Q14,
psEncCtrl->sCmn.pitchL,
invGains_Q16, 16,
psEnc->sCmn.subfr_length,
psEnc->sCmn.predictLPCOrder);
} else {
/************/
/* UNVOICED */
/************/
/* Create signal with prepended subframes, scaled by inverse gains */
x_ptr =
psEnc->x_buf + psEnc->sCmn.frame_length -
psEnc->sCmn.predictLPCOrder;
x_pre_ptr = LPC_in_pre;
for (i = 0; i < NB_SUBFR; i++) {
SKP_Silk_scale_copy_vector16(x_pre_ptr, x_ptr,
invGains_Q16[i],
psEnc->sCmn.subfr_length +
psEnc->sCmn.
predictLPCOrder);
x_pre_ptr +=
psEnc->sCmn.subfr_length +
psEnc->sCmn.predictLPCOrder;
x_ptr += psEnc->sCmn.subfr_length;
}
SKP_memset(psEncCtrl->LTPCoef_Q14, 0,
NB_SUBFR * LTP_ORDER * sizeof(int16_t));
psEncCtrl->LTPredCodGain_Q7 = 0;
}
/* LPC_in_pre contains the LTP-filtered input for voiced, and the unfiltered input for unvoiced */
TIC(FIND_LPC)
SKP_Silk_find_LPC_FIX(NLSF_Q15, &psEncCtrl->sCmn.NLSFInterpCoef_Q2,
psEnc->sPred.prev_NLSFq_Q15,
psEnc->sCmn.useInterpolatedNLSFs * (1 -
psEnc->
sCmn.
first_frame_after_reset),
psEnc->sCmn.predictLPCOrder, LPC_in_pre,
psEnc->sCmn.subfr_length +
psEnc->sCmn.predictLPCOrder);
TOC(FIND_LPC)
/* Quantize LSFs */
TIC(PROCESS_LSFS)
SKP_Silk_process_NLSFs_FIX(psEnc, psEncCtrl, NLSF_Q15);
TOC(PROCESS_LSFS)
/* Calculate residual energy using quantized LPC coefficients */
SKP_Silk_residual_energy_FIX(psEncCtrl->ResNrg, psEncCtrl->ResNrgQ,
LPC_in_pre, (const int16_t(*)[])psEncCtrl->PredCoef_Q12,
local_gains_Qx, Qx,
psEnc->sCmn.subfr_length,
psEnc->sCmn.predictLPCOrder);
/* Copy to prediction struct for use in next frame for fluctuation reduction */
SKP_memcpy(psEnc->sPred.prev_NLSFq_Q15, NLSF_Q15,
psEnc->sCmn.predictLPCOrder * sizeof(int));
}
/* Control internal sampling rate */
SKP_int silk_control_audio_bandwidth(
silk_encoder_state *psEncC /* I/O Pointer to Silk encoder state */
)
{
SKP_int fs_kHz;
SKP_int32 fs_Hz;
fs_kHz = psEncC->fs_kHz;
fs_Hz = SKP_SMULBB( fs_kHz, 1000 );
if( fs_Hz == 0 ) {
/* Encoder has just been initialized */
fs_Hz = SKP_min( psEncC->desiredInternal_fs_Hz, psEncC->API_fs_Hz );
fs_kHz = SKP_DIV32_16( fs_Hz, 1000 );
} else if( fs_Hz > psEncC->API_fs_Hz || fs_Hz > psEncC->maxInternal_fs_Hz || fs_Hz < psEncC->minInternal_fs_Hz ) {
/* Make sure internal rate is not higher than external rate or maximum allowed, or lower than minimum allowed */
fs_Hz = psEncC->API_fs_Hz;
fs_Hz = SKP_min( fs_Hz, psEncC->maxInternal_fs_Hz );
fs_Hz = SKP_max( fs_Hz, psEncC->minInternal_fs_Hz );
fs_kHz = SKP_DIV32_16( fs_Hz, 1000 );
} else {
/* State machine for the internal sampling rate switching */
if( psEncC->sLP.transition_frame_no >= TRANSITION_FRAMES ) {
/* Stop transition phase */
psEncC->sLP.mode = 0;
}
if( psEncC->allow_bandwidth_switch ) {
/* Check if we should switch down */
if( SKP_SMULBB( psEncC->fs_kHz, 1000 ) > psEncC->desiredInternal_fs_Hz )
{
/* Switch down */
if( psEncC->sLP.mode == 0 ) {
/* New transition */
psEncC->sLP.transition_frame_no = TRANSITION_FRAMES;
/* Reset transition filter state */
SKP_memset( psEncC->sLP.In_LP_State, 0, sizeof( psEncC->sLP.In_LP_State ) );
}
if( psEncC->sLP.transition_frame_no <= 0 ) {
/* Stop transition phase */
psEncC->sLP.mode = 0;
/* Switch to a lower sample frequency */
fs_kHz = psEncC->fs_kHz == 16 ? 12 : 8;
} else {
/* Direction: down (at double speed) */
psEncC->sLP.mode = -2;
}
}
else
/* Check if we should switch up */
if( SKP_SMULBB( psEncC->fs_kHz, 1000 ) < psEncC->desiredInternal_fs_Hz )
{
/* Switch up */
if( psEncC->sLP.mode == 0 ) {
/* Switch to a higher sample frequency */
fs_kHz = psEncC->fs_kHz == 8 ? 12 : 16;
/* New transition */
psEncC->sLP.transition_frame_no = 0;
/* Reset transition filter state */
SKP_memset( psEncC->sLP.In_LP_State, 0, sizeof( psEncC->sLP.In_LP_State ) );
}
/* Direction: up */
psEncC->sLP.mode = 1;
}
}
}
#ifdef FORCE_INTERNAL_FS_KHZ
fs_kHz = FORCE_INTERNAL_FS_KHZ;
#endif
return fs_kHz;
}
/* Limit, stabilize, convert and quantize NLSFs. */
void SKP_Silk_process_NLSFs_FIX(
SKP_Silk_encoder_state_FIX *psEnc, /* I/O Encoder state FIX */
SKP_Silk_encoder_control_FIX *psEncCtrl, /* I/O Encoder control FIX */
SKP_int *pNLSF_Q15 /* I/O Normalized LSFs (quant out) (0 - (2^15-1)) */
)
{
SKP_int doInterpolate;
SKP_int pNLSFW_Q6[ MAX_LPC_ORDER ];
SKP_int NLSF_mu_Q15, NLSF_mu_fluc_red_Q16;
SKP_int32 i_sqr_Q15;
const SKP_Silk_NLSF_CB_struct *psNLSF_CB;
/* Used only for NLSF interpolation */
SKP_int pNLSF0_temp_Q15[ MAX_LPC_ORDER ];
SKP_int pNLSFW0_temp_Q6[ MAX_LPC_ORDER ];
SKP_int i;
SKP_assert( psEnc->speech_activity_Q8 >= 0 );
SKP_assert( psEnc->speech_activity_Q8 <= 256 );
SKP_assert( psEncCtrl->sparseness_Q8 >= 0 );
SKP_assert( psEncCtrl->sparseness_Q8 <= 256 );
SKP_assert( psEncCtrl->sCmn.sigtype == SIG_TYPE_VOICED || psEncCtrl->sCmn.sigtype == SIG_TYPE_UNVOICED );
/***********************/
/* Calculate mu values */
/***********************/
if( psEncCtrl->sCmn.sigtype == SIG_TYPE_VOICED ) {
/* NLSF_mu = 0.002f - 0.001f * psEnc->speech_activity; */
/* NLSF_mu_fluc_red = 0.1f - 0.05f * psEnc->speech_activity; */
NLSF_mu_Q15 = SKP_SMLAWB( 66, -8388, psEnc->speech_activity_Q8 );
NLSF_mu_fluc_red_Q16 = SKP_SMLAWB( 6554, -838848, psEnc->speech_activity_Q8 );
} else {
/* NLSF_mu = 0.005f - 0.004f * psEnc->speech_activity; */
/* NLSF_mu_fluc_red = 0.2f - 0.1f * psEnc->speech_activity - 0.1f * psEncCtrl->sparseness; */
NLSF_mu_Q15 = SKP_SMLAWB( 164, -33554, psEnc->speech_activity_Q8 );
NLSF_mu_fluc_red_Q16 = SKP_SMLAWB( 13107, -1677696, psEnc->speech_activity_Q8 + psEncCtrl->sparseness_Q8 );
}
SKP_assert( NLSF_mu_Q15 >= 0 );
SKP_assert( NLSF_mu_Q15 <= 164 );
SKP_assert( NLSF_mu_fluc_red_Q16 >= 0 );
SKP_assert( NLSF_mu_fluc_red_Q16 <= 13107 );
NLSF_mu_Q15 = SKP_max( NLSF_mu_Q15, 1 );
/* Calculate NLSF weights */
TIC(NLSF_weights_FIX)
SKP_Silk_NLSF_VQ_weights_laroia( pNLSFW_Q6, pNLSF_Q15, psEnc->sCmn.predictLPCOrder );
TOC(NLSF_weights_FIX)
/* Update NLSF weights for interpolated NLSFs */
doInterpolate = ( psEnc->sCmn.useInterpolatedNLSFs == 1 ) && ( psEncCtrl->sCmn.NLSFInterpCoef_Q2 < ( 1 << 2 ) );
if( doInterpolate ) {
/* Calculate the interpolated NLSF vector for the first half */
SKP_Silk_interpolate( pNLSF0_temp_Q15, psEnc->sPred.prev_NLSFq_Q15, pNLSF_Q15,
psEncCtrl->sCmn.NLSFInterpCoef_Q2, psEnc->sCmn.predictLPCOrder );
/* Calculate first half NLSF weights for the interpolated NLSFs */
TIC(NLSF_weights_FIX)
SKP_Silk_NLSF_VQ_weights_laroia( pNLSFW0_temp_Q6, pNLSF0_temp_Q15, psEnc->sCmn.predictLPCOrder );
TOC(NLSF_weights_FIX)
/* Update NLSF weights with contribution from first half */
i_sqr_Q15 = SKP_LSHIFT( SKP_SMULBB( psEncCtrl->sCmn.NLSFInterpCoef_Q2, psEncCtrl->sCmn.NLSFInterpCoef_Q2 ), 11 );
for( i = 0; i < psEnc->sCmn.predictLPCOrder; i++ ) {
pNLSFW_Q6[ i ] = SKP_SMLAWB( SKP_RSHIFT( pNLSFW_Q6[ i ], 1 ), pNLSFW0_temp_Q6[ i ], i_sqr_Q15 );
SKP_assert( pNLSFW_Q6[ i ] <= SKP_int16_MAX );
SKP_assert( pNLSFW_Q6[ i ] >= 1 );
}
}
/* Set pointer to the NLSF codebook for the current signal type and LPC order */
psNLSF_CB = psEnc->sCmn.psNLSF_CB[ psEncCtrl->sCmn.sigtype ];
/* Quantize NLSF parameters given the trained NLSF codebooks */
TIC(MSVQ_encode_FIX)
SKP_Silk_NLSF_MSVQ_encode_FIX( psEncCtrl->sCmn.NLSFIndices, pNLSF_Q15, psNLSF_CB,
psEnc->sPred.prev_NLSFq_Q15, pNLSFW_Q6, NLSF_mu_Q15, NLSF_mu_fluc_red_Q16,
psEnc->sCmn.NLSF_MSVQ_Survivors, psEnc->sCmn.predictLPCOrder, psEnc->sCmn.first_frame_after_reset );
TOC(MSVQ_encode_FIX)
/* Convert quantized NLSFs back to LPC coefficients */
SKP_Silk_NLSF2A_stable( psEncCtrl->PredCoef_Q12[ 1 ], pNLSF_Q15, psEnc->sCmn.predictLPCOrder );
if( doInterpolate ) {
/* Calculate the interpolated, quantized LSF vector for the first half */
SKP_Silk_interpolate( pNLSF0_temp_Q15, psEnc->sPred.prev_NLSFq_Q15, pNLSF_Q15,
psEncCtrl->sCmn.NLSFInterpCoef_Q2, psEnc->sCmn.predictLPCOrder );
/* Convert back to LPC coefficients */
SKP_Silk_NLSF2A_stable( psEncCtrl->PredCoef_Q12[ 0 ], pNLSF0_temp_Q15, psEnc->sCmn.predictLPCOrder );
} else {
/* Copy LPC coefficients for first half from second half */
SKP_memcpy( psEncCtrl->PredCoef_Q12[ 0 ], psEncCtrl->PredCoef_Q12[ 1 ], psEnc->sCmn.predictLPCOrder * sizeof( SKP_int16 ) );
}
}
