ref: 0ed6577500c8e388ed1957d6ee8216469164a38f
dir: /silk/float/silk_pitch_analysis_core_FLP.c/
/***********************************************************************
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(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
***********************************************************************/
/*****************************************************************************
*
* Pitch analyser function
*
******************************************************************************/
#include "silk_SigProc_FLP.h"
#include "silk_SigProc_FIX.h"
#include "silk_pitch_est_defines.h"
#define SCRATCH_SIZE 22
/************************************************************/
/* Definitions */
/************************************************************/
#define eps 1.192092896e-07f
/************************************************************/
/* Internally used functions */
/************************************************************/
static void silk_P_Ana_calc_corr_st3(
SKP_float cross_corr_st3[ PE_MAX_NB_SUBFR ][ PE_NB_CBKS_STAGE3_MAX ][ PE_NB_STAGE3_LAGS ], /* O 3 DIM correlation array */
const SKP_float signal[], /* I vector to correlate */
SKP_int start_lag, /* I start lag */
SKP_int sf_length, /* I sub frame length */
SKP_int nb_subfr, /* I number of subframes */
SKP_int complexity /* I Complexity setting */
);
static void silk_P_Ana_calc_energy_st3(
SKP_float energies_st3[ PE_MAX_NB_SUBFR ][ PE_NB_CBKS_STAGE3_MAX ][ PE_NB_STAGE3_LAGS ], /* O 3 DIM correlation array */
const SKP_float signal[], /* I vector to correlate */
SKP_int start_lag, /* I start lag */
SKP_int sf_length, /* I sub frame length */
SKP_int nb_subfr, /* I number of subframes */
SKP_int complexity /* I Complexity setting */
);
//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
//% CORE PITCH ANALYSIS FUNCTION %
//%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
SKP_int silk_pitch_analysis_core_FLP( /* O voicing estimate: 0 voiced, 1 unvoiced */
const SKP_float *signal, /* I signal of length PE_FRAME_LENGTH_MS*Fs_kHz */
SKP_int *pitch_out, /* O 4 pitch lag values */
SKP_int16 *lagIndex, /* O lag Index */
SKP_int8 *contourIndex, /* O pitch contour Index */
SKP_float *LTPCorr, /* I/O normalized correlation; input: value from previous frame */
SKP_int prevLag, /* I last lag of previous frame; set to zero is unvoiced */
const SKP_float search_thres1, /* I first stage threshold for lag candidates 0 - 1 */
const SKP_float search_thres2, /* I final threshold for lag candidates 0 - 1 */
const SKP_int Fs_kHz, /* I sample frequency (kHz) */
const SKP_int complexity, /* I Complexity setting, 0-2, where 2 is highest */
const SKP_int nb_subfr /* I number of 5 ms subframes */
)
{
SKP_int i, k, d, j;
SKP_float signal_8kHz[ PE_MAX_FRAME_LENGTH_MS * 8 ];
SKP_float signal_4kHz[ PE_MAX_FRAME_LENGTH_MS * 4 ];
SKP_int16 signal_8_FIX[ PE_MAX_FRAME_LENGTH_MS * 8 ];
SKP_int16 signal_4_FIX[ PE_MAX_FRAME_LENGTH_MS * 4 ];
SKP_int32 filt_state[ 6 ];
SKP_float threshold, contour_bias;
SKP_float C[ PE_MAX_NB_SUBFR][ (PE_MAX_LAG >> 1) + 5 ];
SKP_float CC[ PE_NB_CBKS_STAGE2_EXT ];
const SKP_float *target_ptr, *basis_ptr;
double cross_corr, normalizer, energy, energy_tmp;
SKP_int d_srch[ PE_D_SRCH_LENGTH ];
SKP_int16 d_comp[ (PE_MAX_LAG >> 1) + 5 ];
SKP_int length_d_srch, length_d_comp;
SKP_float Cmax, CCmax, CCmax_b, CCmax_new_b, CCmax_new;
SKP_int CBimax, CBimax_new, lag, start_lag, end_lag, lag_new;
SKP_int cbk_size;
SKP_float lag_log2, prevLag_log2, delta_lag_log2_sqr;
SKP_float energies_st3[ PE_MAX_NB_SUBFR ][ PE_NB_CBKS_STAGE3_MAX ][ PE_NB_STAGE3_LAGS ];
SKP_float cross_corr_st3[ PE_MAX_NB_SUBFR ][ PE_NB_CBKS_STAGE3_MAX ][ PE_NB_STAGE3_LAGS ];
SKP_int lag_counter;
SKP_int frame_length, frame_length_8kHz, frame_length_4kHz;
SKP_int sf_length, sf_length_8kHz, sf_length_4kHz;
SKP_int min_lag, min_lag_8kHz, min_lag_4kHz;
SKP_int max_lag, max_lag_8kHz, max_lag_4kHz;
SKP_int nb_cbk_search;
const SKP_int8 *Lag_CB_ptr;
/* Check for valid sampling frequency */
SKP_assert( Fs_kHz == 8 || Fs_kHz == 12 || Fs_kHz == 16 );
/* Check for valid complexity setting */
SKP_assert( complexity >= SigProc_PE_MIN_COMPLEX );
SKP_assert( complexity <= SigProc_PE_MAX_COMPLEX );
SKP_assert( search_thres1 >= 0.0f && search_thres1 <= 1.0f );
SKP_assert( search_thres2 >= 0.0f && search_thres2 <= 1.0f );
/* Setup frame lengths max / min lag for the sampling frequency */
frame_length = ( PE_LTP_MEM_LENGTH_MS + nb_subfr * PE_SUBFR_LENGTH_MS ) * Fs_kHz;
frame_length_4kHz = ( PE_LTP_MEM_LENGTH_MS + nb_subfr * PE_SUBFR_LENGTH_MS ) * 4;
frame_length_8kHz = ( PE_LTP_MEM_LENGTH_MS + nb_subfr * PE_SUBFR_LENGTH_MS ) * 8;
sf_length = PE_SUBFR_LENGTH_MS * Fs_kHz;
sf_length_4kHz = PE_SUBFR_LENGTH_MS * 4;
sf_length_8kHz = PE_SUBFR_LENGTH_MS * 8;
min_lag = PE_MIN_LAG_MS * Fs_kHz;
min_lag_4kHz = PE_MIN_LAG_MS * 4;
min_lag_8kHz = PE_MIN_LAG_MS * 8;
max_lag = PE_MAX_LAG_MS * Fs_kHz - 1;
max_lag_4kHz = PE_MAX_LAG_MS * 4;
max_lag_8kHz = PE_MAX_LAG_MS * 8 - 1;
SKP_memset(C, 0, sizeof(SKP_float) * nb_subfr * ((PE_MAX_LAG >> 1) + 5));
/* Resample from input sampled at Fs_kHz to 8 kHz */
if( Fs_kHz == 16 ) {
/* Resample to 16 -> 8 khz */
SKP_int16 signal_16_FIX[ 16 * PE_MAX_FRAME_LENGTH_MS ];
SKP_float2short_array( signal_16_FIX, signal, frame_length );
SKP_memset( filt_state, 0, 2 * sizeof( SKP_int32 ) );
silk_resampler_down2( filt_state, signal_8_FIX, signal_16_FIX, frame_length );
SKP_short2float_array( signal_8kHz, signal_8_FIX, frame_length_8kHz );
} else if( Fs_kHz == 12 ) {
/* Resample to 12 -> 8 khz */
SKP_int16 signal_12_FIX[ 12 * PE_MAX_FRAME_LENGTH_MS ];
SKP_float2short_array( signal_12_FIX, signal, frame_length );
SKP_memset( filt_state, 0, 6 * sizeof( SKP_int32 ) );
silk_resampler_down2_3( filt_state, signal_8_FIX, signal_12_FIX, frame_length );
SKP_short2float_array( signal_8kHz, signal_8_FIX, frame_length_8kHz );
} else {
SKP_assert( Fs_kHz == 8 );
SKP_float2short_array( signal_8_FIX, signal, frame_length_8kHz );
}
/* Decimate again to 4 kHz */
SKP_memset( filt_state, 0, 2 * sizeof( SKP_int32 ) );
silk_resampler_down2( filt_state, signal_4_FIX, signal_8_FIX, frame_length_8kHz );
SKP_short2float_array( signal_4kHz, signal_4_FIX, frame_length_4kHz );
/* Low-pass filter */
for( i = frame_length_4kHz - 1; i > 0; i-- ) {
signal_4kHz[ i ] += signal_4kHz[ i - 1 ];
}
/******************************************************************************
* FIRST STAGE, operating in 4 khz
******************************************************************************/
target_ptr = &signal_4kHz[ SKP_LSHIFT( sf_length_4kHz, 2 ) ];
for( k = 0; k < nb_subfr >> 1; k++ ) {
/* Check that we are within range of the array */
SKP_assert( target_ptr >= signal_4kHz );
SKP_assert( target_ptr + sf_length_8kHz <= signal_4kHz + frame_length_4kHz );
basis_ptr = target_ptr - min_lag_4kHz;
/* Check that we are within range of the array */
SKP_assert( basis_ptr >= signal_4kHz );
SKP_assert( basis_ptr + sf_length_8kHz <= signal_4kHz + frame_length_4kHz );
/* Calculate first vector products before loop */
cross_corr = silk_inner_product_FLP( target_ptr, basis_ptr, sf_length_8kHz );
normalizer = silk_energy_FLP( basis_ptr, sf_length_8kHz ) + sf_length_8kHz * 4000.0f;
C[ 0 ][ min_lag_4kHz ] += (SKP_float)(cross_corr / sqrt(normalizer));
/* From now on normalizer is computed recursively */
for(d = min_lag_4kHz + 1; d <= max_lag_4kHz; d++) {
basis_ptr--;
/* Check that we are within range of the array */
SKP_assert( basis_ptr >= signal_4kHz );
SKP_assert( basis_ptr + sf_length_8kHz <= signal_4kHz + frame_length_4kHz );
cross_corr = silk_inner_product_FLP(target_ptr, basis_ptr, sf_length_8kHz);
/* Add contribution of new sample and remove contribution from oldest sample */
normalizer +=
basis_ptr[ 0 ] * basis_ptr[ 0 ] -
basis_ptr[ sf_length_8kHz ] * basis_ptr[ sf_length_8kHz ];
C[ 0 ][ d ] += (SKP_float)(cross_corr / sqrt( normalizer ));
}
/* Update target pointer */
target_ptr += sf_length_8kHz;
}
/* Apply short-lag bias */
for( i = max_lag_4kHz; i >= min_lag_4kHz; i-- ) {
C[ 0 ][ i ] -= C[ 0 ][ i ] * i / 4096.0f;
}
/* Sort */
length_d_srch = 4 + 2 * complexity;
SKP_assert( 3 * length_d_srch <= PE_D_SRCH_LENGTH );
silk_insertion_sort_decreasing_FLP( &C[ 0 ][ min_lag_4kHz ], d_srch, max_lag_4kHz - min_lag_4kHz + 1, length_d_srch );
/* Escape if correlation is very low already here */
Cmax = C[ 0 ][ min_lag_4kHz ];
target_ptr = &signal_4kHz[ SKP_SMULBB( sf_length_4kHz, nb_subfr ) ];
energy = 1000.0f;
for( i = 0; i < SKP_LSHIFT( sf_length_4kHz, 2 ); i++ ) {
energy += target_ptr[i] * target_ptr[i];
}
threshold = Cmax * Cmax;
if( energy / 16.0f > threshold ) {
SKP_memset( pitch_out, 0, nb_subfr * sizeof( SKP_int ) );
*LTPCorr = 0.0f;
*lagIndex = 0;
*contourIndex = 0;
return 1;
}
threshold = search_thres1 * Cmax;
for( i = 0; i < length_d_srch; i++ ) {
/* Convert to 8 kHz indices for the sorted correlation that exceeds the threshold */
if( C[ 0 ][ min_lag_4kHz + i ] > threshold ) {
d_srch[ i ] = SKP_LSHIFT( d_srch[ i ] + min_lag_4kHz, 1 );
} else {
length_d_srch = i;
break;
}
}
SKP_assert( length_d_srch > 0 );
for( i = min_lag_8kHz - 5; i < max_lag_8kHz + 5; i++ ) {
d_comp[ i ] = 0;
}
for( i = 0; i < length_d_srch; i++ ) {
d_comp[ d_srch[ i ] ] = 1;
}
/* Convolution */
for( i = max_lag_8kHz + 3; i >= min_lag_8kHz; i-- ) {
d_comp[ i ] += d_comp[ i - 1 ] + d_comp[ i - 2 ];
}
length_d_srch = 0;
for( i = min_lag_8kHz; i < max_lag_8kHz + 1; i++ ) {
if( d_comp[ i + 1 ] > 0 ) {
d_srch[ length_d_srch ] = i;
length_d_srch++;
}
}
/* Convolution */
for( i = max_lag_8kHz + 3; i >= min_lag_8kHz; i-- ) {
d_comp[ i ] += d_comp[ i - 1 ] + d_comp[ i - 2 ] + d_comp[ i - 3 ];
}
length_d_comp = 0;
for( i = min_lag_8kHz; i < max_lag_8kHz + 4; i++ ) {
if( d_comp[ i ] > 0 ) {
d_comp[ length_d_comp ] = (SKP_int16)( i - 2 );
length_d_comp++;
}
}
/**********************************************************************************
** SECOND STAGE, operating at 8 kHz, on lag sections with high correlation
*************************************************************************************/
/*********************************************************************************
* Find energy of each subframe projected onto its history, for a range of delays
*********************************************************************************/
SKP_memset( C, 0, PE_MAX_NB_SUBFR*((PE_MAX_LAG >> 1) + 5) * sizeof(SKP_float)); // Is this needed?
if( Fs_kHz == 8 ) {
target_ptr = &signal[ PE_LTP_MEM_LENGTH_MS * 8 ];
} else {
target_ptr = &signal_8kHz[ PE_LTP_MEM_LENGTH_MS * 8 ];
}
for( k = 0; k < nb_subfr; k++ ) {
energy_tmp = silk_energy_FLP( target_ptr, sf_length_8kHz );
for( j = 0; j < length_d_comp; j++ ) {
d = d_comp[ j ];
basis_ptr = target_ptr - d;
cross_corr = silk_inner_product_FLP( basis_ptr, target_ptr, sf_length_8kHz );
energy = silk_energy_FLP( basis_ptr, sf_length_8kHz );
if (cross_corr > 0.0f) {
C[ k ][ d ] = (SKP_float)(cross_corr * cross_corr / (energy * energy_tmp + eps));
} else {
C[ k ][ d ] = 0.0f;
}
}
target_ptr += sf_length_8kHz;
}
/* search over lag range and lags codebook */
/* scale factor for lag codebook, as a function of center lag */
CCmax = 0.0f; /* This value doesn't matter */
CCmax_b = -1000.0f;
CBimax = 0; /* To avoid returning undefined lag values */
lag = -1; /* To check if lag with strong enough correlation has been found */
if( prevLag > 0 ) {
if( Fs_kHz == 12 ) {
prevLag = SKP_LSHIFT( prevLag, 1 ) / 3;
} else if( Fs_kHz == 16 ) {
prevLag = SKP_RSHIFT( prevLag, 1 );
}
prevLag_log2 = silk_log2((SKP_float)prevLag);
} else {
prevLag_log2 = 0;
}
/* Setup stage 2 codebook based on number of subframes */
if( nb_subfr == PE_MAX_NB_SUBFR ) {
cbk_size = PE_NB_CBKS_STAGE2_EXT;
Lag_CB_ptr = &silk_CB_lags_stage2[ 0 ][ 0 ];
if( Fs_kHz == 8 && complexity > SigProc_PE_MIN_COMPLEX ) {
/* If input is 8 khz use a larger codebook here because it is last stage */
nb_cbk_search = PE_NB_CBKS_STAGE2_EXT;
} else {
nb_cbk_search = PE_NB_CBKS_STAGE2;
}
} else {
cbk_size = PE_NB_CBKS_STAGE2_10MS;
Lag_CB_ptr = &silk_CB_lags_stage2_10_ms[ 0 ][ 0 ];
nb_cbk_search = PE_NB_CBKS_STAGE2_10MS;
}
for( k = 0; k < length_d_srch; k++ ) {
d = d_srch[ k ];
for( j = 0; j < nb_cbk_search; j++ ) {
CC[j] = 0.0f;
for( i = 0; i < nb_subfr; i++ ) {
/* Try all codebooks */
CC[ j ] += C[ i ][ d + matrix_ptr( Lag_CB_ptr, i, j, cbk_size )];
}
}
/* Find best codebook */
CCmax_new = -1000.0f;
CBimax_new = 0;
for( i = 0; i < nb_cbk_search; i++ ) {
if( CC[ i ] > CCmax_new ) {
CCmax_new = CC[ i ];
CBimax_new = i;
}
}
CCmax_new = SKP_max_float(CCmax_new, 0.0f); /* To avoid taking square root of negative number later */
CCmax_new_b = CCmax_new;
/* Bias towards shorter lags */
lag_log2 = silk_log2((SKP_float)d);
CCmax_new_b -= PE_SHORTLAG_BIAS * nb_subfr * lag_log2;
/* Bias towards previous lag */
if ( prevLag > 0 ) {
delta_lag_log2_sqr = lag_log2 - prevLag_log2;
delta_lag_log2_sqr *= delta_lag_log2_sqr;
CCmax_new_b -= PE_PREVLAG_BIAS * nb_subfr * (*LTPCorr) * delta_lag_log2_sqr / (delta_lag_log2_sqr + 0.5f);
}
if ( CCmax_new_b > CCmax_b && /* Find maximum biased correlation */
CCmax_new > nb_subfr * search_thres2 * search_thres2 && /* Correlation needs to be high enough to be voiced */
silk_CB_lags_stage2[ 0 ][ CBimax_new ] <= min_lag_8kHz /* Lag must be in range */
) {
CCmax_b = CCmax_new_b;
CCmax = CCmax_new;
lag = d;
CBimax = CBimax_new;
}
}
if( lag == -1 ) {
/* No suitable candidate found */
SKP_memset( pitch_out, 0, PE_MAX_NB_SUBFR * sizeof(SKP_int) );
*LTPCorr = 0.0f;
*lagIndex = 0;
*contourIndex = 0;
return 1;
}
if( Fs_kHz > 8 ) {
/* Search in original signal */
/* Compensate for decimation */
SKP_assert( lag == SKP_SAT16( lag ) );
if( Fs_kHz == 12 ) {
lag = SKP_RSHIFT_ROUND( SKP_SMULBB( lag, 3 ), 1 );
} else if( Fs_kHz == 16 ) {
lag = SKP_LSHIFT( lag, 1 );
} else {
lag = SKP_SMULBB( lag, 3 );
}
lag = SKP_LIMIT_int( lag, min_lag, max_lag );
start_lag = SKP_max_int( lag - 2, min_lag );
end_lag = SKP_min_int( lag + 2, max_lag );
lag_new = lag; /* to avoid undefined lag */
CBimax = 0; /* to avoid undefined lag */
SKP_assert( CCmax >= 0.0f );
*LTPCorr = (SKP_float)sqrt( CCmax / nb_subfr ); /* Output normalized correlation */
CCmax = -1000.0f;
/* Calculate the correlations and energies needed in stage 3 */
silk_P_Ana_calc_corr_st3( cross_corr_st3, signal, start_lag, sf_length, nb_subfr, complexity );
silk_P_Ana_calc_energy_st3( energies_st3, signal, start_lag, sf_length, nb_subfr, complexity );
lag_counter = 0;
SKP_assert( lag == SKP_SAT16( lag ) );
contour_bias = PE_FLATCONTOUR_BIAS / lag;
/* Setup cbk parameters acording to complexity setting and frame length */
if( nb_subfr == PE_MAX_NB_SUBFR ) {
nb_cbk_search = (SKP_int)silk_nb_cbk_searchs_stage3[ complexity ];
cbk_size = PE_NB_CBKS_STAGE3_MAX;
Lag_CB_ptr = &silk_CB_lags_stage3[ 0 ][ 0 ];
} else {
nb_cbk_search = PE_NB_CBKS_STAGE3_10MS;
cbk_size = PE_NB_CBKS_STAGE3_10MS;
Lag_CB_ptr = &silk_CB_lags_stage3_10_ms[ 0 ][ 0 ];
}
for( d = start_lag; d <= end_lag; d++ ) {
for( j = 0; j < nb_cbk_search; j++ ) {
cross_corr = 0.0;
energy = eps;
for( k = 0; k < nb_subfr; k++ ) {
energy += energies_st3[ k ][ j ][ lag_counter ];
cross_corr += cross_corr_st3[ k ][ j ][ lag_counter ];
}
if( cross_corr > 0.0 ) {
CCmax_new = (SKP_float)(cross_corr * cross_corr / energy);
/* Reduce depending on flatness of contour */
CCmax_new *= 1.0f - contour_bias * j;
} else {
CCmax_new = 0.0f;
}
if( CCmax_new > CCmax &&
( d + (SKP_int)silk_CB_lags_stage3[ 0 ][ j ] ) <= max_lag
) {
CCmax = CCmax_new;
lag_new = d;
CBimax = j;
}
}
lag_counter++;
}
for( k = 0; k < nb_subfr; k++ ) {
pitch_out[ k ] = lag_new + matrix_ptr( Lag_CB_ptr, k, CBimax, cbk_size );
}
*lagIndex = (SKP_int16)( lag_new - min_lag );
*contourIndex = (SKP_int8)CBimax;
} else {
/* Save Lags and correlation */
SKP_assert( CCmax >= 0.0f );
*LTPCorr = (SKP_float)sqrt( CCmax / nb_subfr ); /* Output normalized correlation */
for( k = 0; k < nb_subfr; k++ ) {
pitch_out[ k ] = lag + matrix_ptr( Lag_CB_ptr, k, CBimax, cbk_size );
}
*lagIndex = (SKP_int16)( lag - min_lag );
*contourIndex = (SKP_int8)CBimax;
}
SKP_assert( *lagIndex >= 0 );
/* return as voiced */
return 0;
}
static void silk_P_Ana_calc_corr_st3(
SKP_float cross_corr_st3[ PE_MAX_NB_SUBFR ][ PE_NB_CBKS_STAGE3_MAX ][ PE_NB_STAGE3_LAGS ], /* O 3 DIM correlation array */
const SKP_float signal[], /* I vector to correlate */
SKP_int start_lag, /* I start lag */
SKP_int sf_length, /* I sub frame length */
SKP_int nb_subfr, /* I number of subframes */
SKP_int complexity /* I Complexity setting */
)
/***********************************************************************
Calculates the correlations used in stage 3 search. In order to cover
the whole lag codebook for all the searched offset lags (lag +- 2),
the following correlations are needed in each sub frame:
sf1: lag range [-8,...,7] total 16 correlations
sf2: lag range [-4,...,4] total 9 correlations
sf3: lag range [-3,....4] total 8 correltions
sf4: lag range [-6,....8] total 15 correlations
In total 48 correlations. The direct implementation computed in worst case
4*12*5 = 240 correlations, but more likely around 120.
**********************************************************************/
{
const SKP_float *target_ptr, *basis_ptr;
SKP_int i, j, k, lag_counter, lag_low, lag_high;
SKP_int nb_cbk_search, delta, idx, cbk_size;
SKP_float scratch_mem[ SCRATCH_SIZE ];
const SKP_int8 *Lag_range_ptr, *Lag_CB_ptr;
SKP_assert( complexity >= SigProc_PE_MIN_COMPLEX );
SKP_assert( complexity <= SigProc_PE_MAX_COMPLEX );
if( nb_subfr == PE_MAX_NB_SUBFR ){
Lag_range_ptr = &silk_Lag_range_stage3[ complexity ][ 0 ][ 0 ];
Lag_CB_ptr = &silk_CB_lags_stage3[ 0 ][ 0 ];
nb_cbk_search = silk_nb_cbk_searchs_stage3[ complexity ];
cbk_size = PE_NB_CBKS_STAGE3_MAX;
} else {
SKP_assert( nb_subfr == PE_MAX_NB_SUBFR >> 1);
Lag_range_ptr = &silk_Lag_range_stage3_10_ms[ 0 ][ 0 ];
Lag_CB_ptr = &silk_CB_lags_stage3_10_ms[ 0 ][ 0 ];
nb_cbk_search = PE_NB_CBKS_STAGE3_10MS;
cbk_size = PE_NB_CBKS_STAGE3_10MS;
}
target_ptr = &signal[ SKP_LSHIFT( sf_length, 2 ) ]; /* Pointer to middle of frame */
for( k = 0; k < nb_subfr; k++ ) {
lag_counter = 0;
/* Calculate the correlations for each subframe */
lag_low = matrix_ptr( Lag_range_ptr, k, 0, 2 );
lag_high = matrix_ptr( Lag_range_ptr, k, 1, 2 );
for( j = lag_low; j <= lag_high; j++ ) {
basis_ptr = target_ptr - ( start_lag + j );
SKP_assert( lag_counter < SCRATCH_SIZE );
scratch_mem[ lag_counter ] = (SKP_float)silk_inner_product_FLP( target_ptr, basis_ptr, sf_length );
lag_counter++;
}
delta = matrix_ptr( Lag_range_ptr, k, 0, 2 );
for( i = 0; i < nb_cbk_search; i++ ) {
/* Fill out the 3 dim array that stores the correlations for */
/* each code_book vector for each start lag */
idx = matrix_ptr( Lag_CB_ptr, k, i, cbk_size ) - delta;
for( j = 0; j < PE_NB_STAGE3_LAGS; j++ ) {
SKP_assert( idx + j < SCRATCH_SIZE );
SKP_assert( idx + j < lag_counter );
cross_corr_st3[ k ][ i ][ j ] = scratch_mem[ idx + j ];
}
}
target_ptr += sf_length;
}
}
static void silk_P_Ana_calc_energy_st3(
SKP_float energies_st3[ PE_MAX_NB_SUBFR ][ PE_NB_CBKS_STAGE3_MAX ][ PE_NB_STAGE3_LAGS ], /* O 3 DIM correlation array */
const SKP_float signal[], /* I vector to correlate */
SKP_int start_lag, /* I start lag */
SKP_int sf_length, /* I sub frame length */
SKP_int nb_subfr, /* I number of subframes */
SKP_int complexity /* I Complexity setting */
)
/****************************************************************
Calculate the energies for first two subframes. The energies are
calculated recursively.
****************************************************************/
{
const SKP_float *target_ptr, *basis_ptr;
double energy;
SKP_int k, i, j, lag_counter;
SKP_int nb_cbk_search, delta, idx, cbk_size, lag_diff;
SKP_float scratch_mem[ SCRATCH_SIZE ];
const SKP_int8 *Lag_range_ptr, *Lag_CB_ptr;
SKP_assert( complexity >= SigProc_PE_MIN_COMPLEX );
SKP_assert( complexity <= SigProc_PE_MAX_COMPLEX );
if( nb_subfr == PE_MAX_NB_SUBFR ){
Lag_range_ptr = &silk_Lag_range_stage3[ complexity ][ 0 ][ 0 ];
Lag_CB_ptr = &silk_CB_lags_stage3[ 0 ][ 0 ];
nb_cbk_search = silk_nb_cbk_searchs_stage3[ complexity ];
cbk_size = PE_NB_CBKS_STAGE3_MAX;
} else {
SKP_assert( nb_subfr == PE_MAX_NB_SUBFR >> 1);
Lag_range_ptr = &silk_Lag_range_stage3_10_ms[ 0 ][ 0 ];
Lag_CB_ptr = &silk_CB_lags_stage3_10_ms[ 0 ][ 0 ];
nb_cbk_search = PE_NB_CBKS_STAGE3_10MS;
cbk_size = PE_NB_CBKS_STAGE3_10MS;
}
target_ptr = &signal[ SKP_LSHIFT( sf_length, 2 ) ];
for( k = 0; k < nb_subfr; k++ ) {
lag_counter = 0;
/* Calculate the energy for first lag */
basis_ptr = target_ptr - ( start_lag + matrix_ptr( Lag_range_ptr, k, 0, 2 ) );
energy = silk_energy_FLP( basis_ptr, sf_length ) + 1e-3;
SKP_assert( energy >= 0.0 );
scratch_mem[lag_counter] = (SKP_float)energy;
lag_counter++;
lag_diff = ( matrix_ptr( Lag_range_ptr, k, 1, 2 ) - matrix_ptr( Lag_range_ptr, k, 0, 2 ) + 1 );
for( i = 1; i < lag_diff; i++ ) {
/* remove part outside new window */
energy -= basis_ptr[sf_length - i] * basis_ptr[sf_length - i];
SKP_assert( energy >= 0.0 );
/* add part that comes into window */
energy += basis_ptr[ -i ] * basis_ptr[ -i ];
SKP_assert( energy >= 0.0 );
SKP_assert( lag_counter < SCRATCH_SIZE );
scratch_mem[lag_counter] = (SKP_float)energy;
lag_counter++;
}
delta = matrix_ptr( Lag_range_ptr, k, 0, 2 );
for( i = 0; i < nb_cbk_search; i++ ) {
/* Fill out the 3 dim array that stores the correlations for */
/* each code_book vector for each start lag */
idx = matrix_ptr( Lag_CB_ptr, k, i, cbk_size ) - delta;
for( j = 0; j < PE_NB_STAGE3_LAGS; j++ ) {
SKP_assert( idx + j < SCRATCH_SIZE );
SKP_assert( idx + j < lag_counter );
energies_st3[ k ][ i ][ j ] = scratch_mem[ idx + j ];
SKP_assert( energies_st3[ k ][ i ][ j ] >= 0.0f );
}
}
target_ptr += sf_length;
}
}