/* Predictive dequantizer for NLSF residuals */
static OPUS_INLINE void silk_NLSF_residual_dequant( /* O Returns RD value in Q30 */
opus_int16 x_Q10[], /* O Output [ order ] */
const opus_int8 indices[], /* I Quantization indices [ order ] */
const opus_uint8 pred_coef_Q8[], /* I Backward predictor coefs [ order ] */
const opus_int quant_step_size_Q16, /* I Quantization step size */
const opus_int16 order /* I Number of input values */
)
{
opus_int i, out_Q10, pred_Q10;
out_Q10 = 0;
for( i = order-1; i >= 0; i-- ) {
pred_Q10 = silk_RSHIFT( silk_SMULBB( out_Q10, (opus_int16)pred_coef_Q8[ i ] ), 8 );
out_Q10 = silk_LSHIFT( indices[ i ], 10 );
if( out_Q10 > 0 ) {
out_Q10 = silk_SUB16( out_Q10, SILK_FIX_CONST( NLSF_QUANT_LEVEL_ADJ, 10 ) );
} else if( out_Q10 < 0 ) {
out_Q10 = silk_ADD16( out_Q10, SILK_FIX_CONST( NLSF_QUANT_LEVEL_ADJ, 10 ) );
}
out_Q10 = silk_SMLAWB( pred_Q10, (opus_int32)out_Q10, quant_step_size_Q16 );
x_Q10[ i ] = out_Q10;
}
}
/* Delayed-decision quantizer for NLSF residuals */
opus_int32 silk_NLSF_del_dec_quant( /* O Returns RD value in Q25 */
opus_int8 indices[], /* O Quantization indices [ order ] */
const opus_int16 x_Q10[], /* I Input [ order ] */
const opus_int16 w_Q5[], /* I Weights [ order ] */
const opus_uint8 pred_coef_Q8[], /* I Backward predictor coefs [ order ] */
const opus_int16 ec_ix[], /* I Indices to entropy coding tables [ order ] */
const opus_uint8 ec_rates_Q5[], /* I Rates [] */
const opus_int quant_step_size_Q16, /* I Quantization step size */
const opus_int16 inv_quant_step_size_Q6, /* I Inverse quantization step size */
const opus_int32 mu_Q20, /* I R/D tradeoff */
const opus_int16 order /* I Number of input values */
)
{
opus_int i, j, nStates, ind_tmp, ind_min_max, ind_max_min, in_Q10, res_Q10;
opus_int pred_Q10, diff_Q10, out0_Q10, out1_Q10, rate0_Q5, rate1_Q5;
opus_int32 RD_tmp_Q25, min_Q25, min_max_Q25, max_min_Q25, pred_coef_Q16;
opus_int ind_sort[ NLSF_QUANT_DEL_DEC_STATES ];
opus_int8 ind[ NLSF_QUANT_DEL_DEC_STATES ][ MAX_LPC_ORDER ];
opus_int16 prev_out_Q10[ 2 * NLSF_QUANT_DEL_DEC_STATES ];
opus_int32 RD_Q25[ 2 * NLSF_QUANT_DEL_DEC_STATES ];
opus_int32 RD_min_Q25[ NLSF_QUANT_DEL_DEC_STATES ];
opus_int32 RD_max_Q25[ NLSF_QUANT_DEL_DEC_STATES ];
const opus_uint8 *rates_Q5;
silk_assert( (NLSF_QUANT_DEL_DEC_STATES & (NLSF_QUANT_DEL_DEC_STATES-1)) == 0 ); /* must be power of two */
nStates = 1;
RD_Q25[ 0 ] = 0;
prev_out_Q10[ 0 ] = 0;
for( i = order - 1; ; i-- ) {
rates_Q5 = &ec_rates_Q5[ ec_ix[ i ] ];
pred_coef_Q16 = silk_LSHIFT( (opus_int32)pred_coef_Q8[ i ], 8 );
in_Q10 = x_Q10[ i ];
for( j = 0; j < nStates; j++ ) {
pred_Q10 = silk_SMULWB( pred_coef_Q16, prev_out_Q10[ j ] );
res_Q10 = silk_SUB16( in_Q10, pred_Q10 );
ind_tmp = silk_SMULWB( inv_quant_step_size_Q6, res_Q10 );
ind_tmp = silk_LIMIT( ind_tmp, -NLSF_QUANT_MAX_AMPLITUDE_EXT, NLSF_QUANT_MAX_AMPLITUDE_EXT-1 );
ind[ j ][ i ] = (opus_int8)ind_tmp;
/* compute outputs for ind_tmp and ind_tmp + 1 */
out0_Q10 = silk_LSHIFT( ind_tmp, 10 );
out1_Q10 = silk_ADD16( out0_Q10, 1024 );
if( ind_tmp > 0 ) {
out0_Q10 = silk_SUB16( out0_Q10, SILK_FIX_CONST( NLSF_QUANT_LEVEL_ADJ, 10 ) );
out1_Q10 = silk_SUB16( out1_Q10, SILK_FIX_CONST( NLSF_QUANT_LEVEL_ADJ, 10 ) );
} else if( ind_tmp == 0 ) {
out1_Q10 = silk_SUB16( out1_Q10, SILK_FIX_CONST( NLSF_QUANT_LEVEL_ADJ, 10 ) );
} else if( ind_tmp == -1 ) {
out0_Q10 = silk_ADD16( out0_Q10, SILK_FIX_CONST( NLSF_QUANT_LEVEL_ADJ, 10 ) );
} else {
out0_Q10 = silk_ADD16( out0_Q10, SILK_FIX_CONST( NLSF_QUANT_LEVEL_ADJ, 10 ) );
out1_Q10 = silk_ADD16( out1_Q10, SILK_FIX_CONST( NLSF_QUANT_LEVEL_ADJ, 10 ) );
}
out0_Q10 = silk_SMULWB( out0_Q10, quant_step_size_Q16 );
out1_Q10 = silk_SMULWB( out1_Q10, quant_step_size_Q16 );
out0_Q10 = silk_ADD16( out0_Q10, pred_Q10 );
out1_Q10 = silk_ADD16( out1_Q10, pred_Q10 );
prev_out_Q10[ j ] = out0_Q10;
prev_out_Q10[ j + nStates ] = out1_Q10;
/* compute RD for ind_tmp and ind_tmp + 1 */
if( ind_tmp + 1 >= NLSF_QUANT_MAX_AMPLITUDE ) {
if( ind_tmp + 1 == NLSF_QUANT_MAX_AMPLITUDE ) {
rate0_Q5 = rates_Q5[ ind_tmp + NLSF_QUANT_MAX_AMPLITUDE ];
rate1_Q5 = 280;
} else {
rate0_Q5 = silk_SMLABB( 280 - 43 * NLSF_QUANT_MAX_AMPLITUDE, 43, ind_tmp );
rate1_Q5 = silk_ADD16( rate0_Q5, 43 );
}
} else if( ind_tmp <= -NLSF_QUANT_MAX_AMPLITUDE ) {
if( ind_tmp == -NLSF_QUANT_MAX_AMPLITUDE ) {
rate0_Q5 = 280;
rate1_Q5 = rates_Q5[ ind_tmp + 1 + NLSF_QUANT_MAX_AMPLITUDE ];
} else {
rate0_Q5 = silk_SMLABB( 280 - 43 * NLSF_QUANT_MAX_AMPLITUDE, -43, ind_tmp );
rate1_Q5 = silk_SUB16( rate0_Q5, 43 );
}
} else {
rate0_Q5 = rates_Q5[ ind_tmp + NLSF_QUANT_MAX_AMPLITUDE ];
rate1_Q5 = rates_Q5[ ind_tmp + 1 + NLSF_QUANT_MAX_AMPLITUDE ];
}
RD_tmp_Q25 = RD_Q25[ j ];
diff_Q10 = silk_SUB16( in_Q10, out0_Q10 );
RD_Q25[ j ] = silk_SMLABB( silk_MLA( RD_tmp_Q25, silk_SMULBB( diff_Q10, diff_Q10 ), w_Q5[ i ] ), mu_Q20, rate0_Q5 );
diff_Q10 = silk_SUB16( in_Q10, out1_Q10 );
RD_Q25[ j + nStates ] = silk_SMLABB( silk_MLA( RD_tmp_Q25, silk_SMULBB( diff_Q10, diff_Q10 ), w_Q5[ i ] ), mu_Q20, rate1_Q5 );
}
if( nStates < NLSF_QUANT_DEL_DEC_STATES ) {
/* double number of states and copy */
for( j = 0; j < nStates; j++ ) {
ind[ j + nStates ][ i ] = ind[ j ][ i ] + 1;
}
nStates = silk_LSHIFT( nStates, 1 );
for( j = nStates; j < NLSF_QUANT_DEL_DEC_STATES; j++ ) {
ind[ j ][ i ] = ind[ j - nStates ][ i ];
}
} else if( i > 0 ) {
/* sort lower and upper half of RD_Q25, pairwise */
for( j = 0; j < NLSF_QUANT_DEL_DEC_STATES; j++ ) {
if( RD_Q25[ j ] > RD_Q25[ j + NLSF_QUANT_DEL_DEC_STATES ] ) {
RD_max_Q25[ j ] = RD_Q25[ j ];
RD_min_Q25[ j ] = RD_Q25[ j + NLSF_QUANT_DEL_DEC_STATES ];
RD_Q25[ j ] = RD_min_Q25[ j ];
RD_Q25[ j + NLSF_QUANT_DEL_DEC_STATES ] = RD_max_Q25[ j ];
/* swap prev_out values */
out0_Q10 = prev_out_Q10[ j ];
prev_out_Q10[ j ] = prev_out_Q10[ j + NLSF_QUANT_DEL_DEC_STATES ];
prev_out_Q10[ j + NLSF_QUANT_DEL_DEC_STATES ] = out0_Q10;
ind_sort[ j ] = j + NLSF_QUANT_DEL_DEC_STATES;
} else {
RD_min_Q25[ j ] = RD_Q25[ j ];
RD_max_Q25[ j ] = RD_Q25[ j + NLSF_QUANT_DEL_DEC_STATES ];
ind_sort[ j ] = j;
}
}
/* compare the highest RD values of the winning half with the lowest one in the losing half, and copy if necessary */
/* afterwards ind_sort[] will contain the indices of the NLSF_QUANT_DEL_DEC_STATES winning RD values */
while( 1 ) {
min_max_Q25 = silk_int32_MAX;
max_min_Q25 = 0;
ind_min_max = 0;
ind_max_min = 0;
for( j = 0; j < NLSF_QUANT_DEL_DEC_STATES; j++ ) {
if( min_max_Q25 > RD_max_Q25[ j ] ) {
min_max_Q25 = RD_max_Q25[ j ];
ind_min_max = j;
}
if( max_min_Q25 < RD_min_Q25[ j ] ) {
max_min_Q25 = RD_min_Q25[ j ];
ind_max_min = j;
}
}
if( min_max_Q25 >= max_min_Q25 ) {
break;
}
/* copy ind_min_max to ind_max_min */
ind_sort[ ind_max_min ] = ind_sort[ ind_min_max ] ^ NLSF_QUANT_DEL_DEC_STATES;
RD_Q25[ ind_max_min ] = RD_Q25[ ind_min_max + NLSF_QUANT_DEL_DEC_STATES ];
prev_out_Q10[ ind_max_min ] = prev_out_Q10[ ind_min_max + NLSF_QUANT_DEL_DEC_STATES ];
RD_min_Q25[ ind_max_min ] = 0;
RD_max_Q25[ ind_min_max ] = silk_int32_MAX;
silk_memcpy( ind[ ind_max_min ], ind[ ind_min_max ], MAX_LPC_ORDER * sizeof( opus_int8 ) );
}
/* increment index if it comes from the upper half */
for( j = 0; j < NLSF_QUANT_DEL_DEC_STATES; j++ ) {
ind[ j ][ i ] += silk_RSHIFT( ind_sort[ j ], NLSF_QUANT_DEL_DEC_STATES_LOG2 );
}
} else { /* i == 0 */
break;
}
}
/* last sample: find winner, copy indices and return RD value */
ind_tmp = 0;
min_Q25 = silk_int32_MAX;
for( j = 0; j < 2 * NLSF_QUANT_DEL_DEC_STATES; j++ ) {
if( min_Q25 > RD_Q25[ j ] ) {
min_Q25 = RD_Q25[ j ];
ind_tmp = j;
}
}
for( j = 0; j < order; j++ ) {
indices[ j ] = ind[ ind_tmp & ( NLSF_QUANT_DEL_DEC_STATES - 1 ) ][ j ];
silk_assert( indices[ j ] >= -NLSF_QUANT_MAX_AMPLITUDE_EXT );
silk_assert( indices[ j ] <= NLSF_QUANT_MAX_AMPLITUDE_EXT );
}
indices[ 0 ] += silk_RSHIFT( ind_tmp, NLSF_QUANT_DEL_DEC_STATES_LOG2 );
silk_assert( indices[ 0 ] <= NLSF_QUANT_MAX_AMPLITUDE_EXT );
silk_assert( min_Q25 >= 0 );
return min_Q25;
}