/* Gains scalar dequantization, uniform on log scale */
void SKP_Silk_gains_dequant(
SKP_int32 gain_Q16[ MAX_NB_SUBFR ], /* O quantized gains */
const SKP_int8 ind[ MAX_NB_SUBFR ], /* I gain indices */
SKP_int8 *prev_ind, /* I/O last index in previous frame */
const SKP_int conditional, /* I first gain is delta coded if 1 */
const SKP_int nb_subfr /* I number of subframes */
)
{
SKP_int k, ind_tmp, double_step_size_threshold;
for( k = 0; k < nb_subfr; k++ ) {
if( k == 0 && conditional == 0 ) {
*prev_ind = ind[ k ];
} else {
/* Delta index */
ind_tmp = ind[ k ] + MIN_DELTA_GAIN_QUANT;
/* Accumulate deltas */
double_step_size_threshold = 2 * MAX_DELTA_GAIN_QUANT - N_LEVELS_QGAIN + *prev_ind;
if( ind_tmp > double_step_size_threshold ) {
*prev_ind += SKP_LSHIFT( ind_tmp, 1 ) - double_step_size_threshold;
} else {
*prev_ind += ind_tmp;
}
}
/* Convert to linear scale and scale */
gain_Q16[ k ] = SKP_Silk_log2lin( SKP_min_32( SKP_SMULWB( INV_SCALE_Q16, *prev_ind ) + OFFSET, 3967 ) ); /* 3967 = 31 in Q7 */
}
}
/* Gain scalar quantization with hysteresis, uniform on log scale */
void SKP_Silk_gains_quant(
SKP_int8 ind[ MAX_NB_SUBFR ], /* O gain indices */
SKP_int32 gain_Q16[ MAX_NB_SUBFR ], /* I/O gains (quantized out) */
SKP_int8 *prev_ind, /* I/O last index in previous frame */
const SKP_int conditional, /* I first gain is delta coded if 1 */
const SKP_int nb_subfr /* I number of subframes */
)
{
SKP_int k, double_step_size_threshold;
for( k = 0; k < nb_subfr; k++ ) {
/* Add half of previous quantization error, convert to log scale, scale, floor() */
ind[ k ] = SKP_SMULWB( SCALE_Q16, SKP_Silk_lin2log( gain_Q16[ k ] ) - OFFSET );
/* Round towards previous quantized gain (hysteresis) */
if( ind[ k ] < *prev_ind ) {
ind[ k ]++;
}
ind[ k ] = SKP_max_int( ind[ k ], 0 );
/* Compute delta indices and limit */
if( k == 0 && conditional == 0 ) {
/* Full index */
ind[ k ] = SKP_LIMIT_int( ind[ k ], *prev_ind + MIN_DELTA_GAIN_QUANT, N_LEVELS_QGAIN - 1 );
*prev_ind = ind[ k ];
} else {
/* Delta index */
ind[ k ] = ind[ k ] - *prev_ind;
/* Double the quantization step size for large gain increases, so that the max gain level can be reached */
double_step_size_threshold = 2 * MAX_DELTA_GAIN_QUANT - N_LEVELS_QGAIN + *prev_ind;
if( ind[ k ] > double_step_size_threshold ) {
ind[ k ] = double_step_size_threshold + SKP_RSHIFT( ind[ k ] - double_step_size_threshold + 1, 1 );
}
ind[ k ] = SKP_LIMIT_int( ind[ k ], MIN_DELTA_GAIN_QUANT, MAX_DELTA_GAIN_QUANT );
/* Accumulate deltas */
if( ind[ k ] > double_step_size_threshold ) {
*prev_ind += SKP_LSHIFT( ind[ k ], 1 ) - double_step_size_threshold;
} else {
*prev_ind += ind[ k ];
}
/* Shift to make non-negative */
ind[ k ] -= MIN_DELTA_GAIN_QUANT;
}
/* Convert to linear scale and scale */
gain_Q16[ k ] = SKP_Silk_log2lin( SKP_min_32( SKP_SMULWB( INV_SCALE_Q16, *prev_ind ) + OFFSET, 3967 ) ); /* 3967 = 31 in Q7 */
}
}
/* High-pass filter with cutoff frequency adaptation based on pitch lag statistics */
void SKP_Silk_HP_variable_cutoff_FIX(
SKP_Silk_encoder_state_FIX *psEnc, /* I/O Encoder state FIX */
SKP_Silk_encoder_control_FIX *psEncCtrl, /* I/O Encoder control FIX */
SKP_int16 *out, /* O high-pass filtered output signal */
const SKP_int16 *in /* I input signal */
)
{
SKP_int quality_Q15;
SKP_int32 B_Q28[ 3 ], A_Q28[ 2 ];
SKP_int32 Fc_Q19, r_Q28, r_Q22;
SKP_int32 pitch_freq_Hz_Q16, pitch_freq_log_Q7, delta_freq_Q7;
/*********************************************/
/* Estimate Low End of Pitch Frequency Range */
/*********************************************/
if( psEnc->sCmn.prev_sigtype == SIG_TYPE_VOICED ) {
/* difference, in log domain */
pitch_freq_Hz_Q16 = SKP_DIV32_16( SKP_LSHIFT( SKP_MUL( psEnc->sCmn.fs_kHz, 1000 ), 16 ), psEnc->sCmn.prevLag );
pitch_freq_log_Q7 = SKP_Silk_lin2log( pitch_freq_Hz_Q16 ) - ( 16 << 7 ); //0x70
/* adjustment based on quality */
quality_Q15 = psEncCtrl->input_quality_bands_Q15[ 0 ];
pitch_freq_log_Q7 = SKP_SUB32( pitch_freq_log_Q7, SKP_SMULWB( SKP_SMULWB( SKP_LSHIFT( quality_Q15, 2 ), quality_Q15 ),
pitch_freq_log_Q7 - SKP_LOG2_VARIABLE_HP_MIN_FREQ_Q7 ) );
pitch_freq_log_Q7 = SKP_ADD32( pitch_freq_log_Q7, SKP_RSHIFT( SKP_FIX_CONST( 0.6, 15 ) - quality_Q15, 9 ) );
//delta_freq = pitch_freq_log - psEnc->variable_HP_smth1;
delta_freq_Q7 = pitch_freq_log_Q7 - SKP_RSHIFT( psEnc->variable_HP_smth1_Q15, 8 );
if( delta_freq_Q7 < 0 ) {
/* less smoothing for decreasing pitch frequency, to track something close to the minimum */
delta_freq_Q7 = SKP_MUL( delta_freq_Q7, 3 );
}
/* limit delta, to reduce impact of outliers */
delta_freq_Q7 = SKP_LIMIT_32( delta_freq_Q7, -SKP_FIX_CONST( VARIABLE_HP_MAX_DELTA_FREQ, 7 ), SKP_FIX_CONST( VARIABLE_HP_MAX_DELTA_FREQ, 7 ) );
/* update smoother */
psEnc->variable_HP_smth1_Q15 = SKP_SMLAWB( psEnc->variable_HP_smth1_Q15,
SKP_MUL( SKP_LSHIFT( psEnc->speech_activity_Q8, 1 ), delta_freq_Q7 ), SKP_FIX_CONST( VARIABLE_HP_SMTH_COEF1, 16 ) );
}
/* second smoother */
psEnc->variable_HP_smth2_Q15 = SKP_SMLAWB( psEnc->variable_HP_smth2_Q15,
psEnc->variable_HP_smth1_Q15 - psEnc->variable_HP_smth2_Q15, SKP_FIX_CONST( VARIABLE_HP_SMTH_COEF2, 16 ) );
/* convert from log scale to Hertz */
psEncCtrl->pitch_freq_low_Hz = SKP_Silk_log2lin( SKP_RSHIFT( psEnc->variable_HP_smth2_Q15, 8 ) );
/* limit frequency range */
psEncCtrl->pitch_freq_low_Hz = SKP_LIMIT_32( psEncCtrl->pitch_freq_low_Hz,
SKP_FIX_CONST( VARIABLE_HP_MIN_FREQ, 0 ), SKP_FIX_CONST( VARIABLE_HP_MAX_FREQ, 0 ) );
/********************************/
/* Compute Filter Coefficients */
/********************************/
/* compute cut-off frequency, in radians */
//Fc_num = (SKP_float)( 0.45f * 2.0f * 3.14159265359 * psEncCtrl->pitch_freq_low_Hz );
//Fc_denom = (SKP_float)( 1e3f * psEnc->sCmn.fs_kHz );
SKP_assert( psEncCtrl->pitch_freq_low_Hz <= SKP_int32_MAX / SKP_RADIANS_CONSTANT_Q19 );
Fc_Q19 = SKP_DIV32_16( SKP_SMULBB( SKP_RADIANS_CONSTANT_Q19, psEncCtrl->pitch_freq_low_Hz ), psEnc->sCmn.fs_kHz ); // range: 3704 - 27787, 11-15 bits
SKP_assert( Fc_Q19 >= 3704 );
SKP_assert( Fc_Q19 <= 27787 );
r_Q28 = SKP_FIX_CONST( 1.0, 28 ) - SKP_MUL( SKP_FIX_CONST( 0.92, 9 ), Fc_Q19 );
SKP_assert( r_Q28 >= 255347779 );
SKP_assert( r_Q28 <= 266690872 );
/* b = r * [ 1; -2; 1 ]; */
/* a = [ 1; -2 * r * ( 1 - 0.5 * Fc^2 ); r^2 ]; */
B_Q28[ 0 ] = r_Q28;
B_Q28[ 1 ] = SKP_LSHIFT( -r_Q28, 1 );
B_Q28[ 2 ] = r_Q28;
// -r * ( 2 - Fc * Fc );
r_Q22 = SKP_RSHIFT( r_Q28, 6 );
A_Q28[ 0 ] = SKP_SMULWW( r_Q22, SKP_SMULWW( Fc_Q19, Fc_Q19 ) - SKP_FIX_CONST( 2.0, 22 ) );
A_Q28[ 1 ] = SKP_SMULWW( r_Q22, r_Q22 );
/********************************/
/* High-Pass Filter */
/********************************/
SKP_Silk_biquad_alt( in, B_Q28, A_Q28, psEnc->sCmn.In_HP_State, out, psEnc->sCmn.frame_length );
}
/* Convert to monic warped prediction coefficients and limit absolute values */
limit_warped_coefs( AR2_Q24, AR1_Q24, warping_Q16, SKP_FIX_CONST( 3.999, 24 ), psEnc->sCmn.shapingLPCOrder );
/* Convert from Q24 to Q13 and store in int16 */
for( i = 0; i < psEnc->sCmn.shapingLPCOrder; i++ ) {
psEncCtrl->AR1_Q13[ k * MAX_SHAPE_LPC_ORDER + i ] = (SKP_int16)SKP_SAT16( SKP_RSHIFT_ROUND( AR1_Q24[ i ], 11 ) );
psEncCtrl->AR2_Q13[ k * MAX_SHAPE_LPC_ORDER + i ] = (SKP_int16)SKP_SAT16( SKP_RSHIFT_ROUND( AR2_Q24[ i ], 11 ) );
}
}
/*****************/
/* Gain tweaking */
/*****************/
/* Increase gains during low speech activity and put lower limit on gains */
gain_mult_Q16 = SKP_Silk_log2lin( -SKP_SMLAWB( -SKP_FIX_CONST( 16.0, 7 ), SNR_adj_dB_Q7, SKP_FIX_CONST( 0.16, 16 ) ) );
gain_add_Q16 = SKP_Silk_log2lin( SKP_SMLAWB( SKP_FIX_CONST( 16.0, 7 ), SKP_FIX_CONST( NOISE_FLOOR_dB, 7 ), SKP_FIX_CONST( 0.16, 16 ) ) );
tmp32 = SKP_Silk_log2lin( SKP_SMLAWB( SKP_FIX_CONST( 16.0, 7 ), SKP_FIX_CONST( RELATIVE_MIN_GAIN_dB, 7 ), SKP_FIX_CONST( 0.16, 16 ) ) );
tmp32 = SKP_SMULWW( psEnc->avgGain_Q16, tmp32 );
gain_add_Q16 = SKP_ADD_SAT32( gain_add_Q16, tmp32 );
SKP_assert( gain_mult_Q16 >= 0 );
for( k = 0; k < NB_SUBFR; k++ ) {
psEncCtrl->Gains_Q16[ k ] = SKP_SMULWW( psEncCtrl->Gains_Q16[ k ], gain_mult_Q16 );
if( psEncCtrl->Gains_Q16[ k ] < 0 ) {
psEncCtrl->Gains_Q16[ k ] = SKP_int32_MAX;
}
}
for( k = 0; k < NB_SUBFR; k++ ) {
psEncCtrl->Gains_Q16[ k ] = SKP_ADD_POS_SAT32( psEncCtrl->Gains_Q16[ k ], gain_add_Q16 );
/* Processing of gains */
void SKP_Silk_process_gains_FIX(
SKP_Silk_encoder_state_FIX *psEnc, /* I/O Encoder state_FIX */
SKP_Silk_encoder_control_FIX *psEncCtrl /* I/O Encoder control_FIX */
)
{
SKP_Silk_shape_state_FIX *psShapeSt = &psEnc->sShape;
SKP_int k;
SKP_int32 s_Q16, InvMaxSqrVal_Q16, gain, gain_squared, ResNrg, ResNrgPart;
/* Gain reduction when LTP coding gain is high */
if( psEncCtrl->sCmn.sigtype == SIG_TYPE_VOICED ) {
/*s = -0.5f * SKP_sigmoid( 0.25f * ( psEncCtrl->LTPredCodGain - 12.0f ) ); */
s_Q16 = -SKP_Silk_sigm_Q15( SKP_RSHIFT_ROUND( psEncCtrl->LTPredCodGain_Q7 - (12 << 7), 4 ) );
for( k = 0; k < NB_SUBFR; k++ ) {
psEncCtrl->Gains_Q16[ k ] = SKP_SMLAWB( psEncCtrl->Gains_Q16[ k ], psEncCtrl->Gains_Q16[ k ], s_Q16 );
}
}
/* Limit the quantized signal */
/* 69 = 21.0f + 16/0.33 */
InvMaxSqrVal_Q16 = SKP_DIV32_16( SKP_Silk_log2lin(
SKP_SMULWB( (69 << 7) - psEncCtrl->current_SNR_dB_Q7, SKP_FIX_CONST( 0.33, 16 )) ), psEnc->sCmn.subfr_length );
for( k = 0; k < NB_SUBFR; k++ ) {
/* Soft limit on ratio residual energy and squared gains */
ResNrg = psEncCtrl->ResNrg[ k ];
ResNrgPart = SKP_SMULWW( ResNrg, InvMaxSqrVal_Q16 );
if( psEncCtrl->ResNrgQ[ k ] > 0 ) {
if( psEncCtrl->ResNrgQ[ k ] < 32 ) {
ResNrgPart = SKP_RSHIFT_ROUND( ResNrgPart, psEncCtrl->ResNrgQ[ k ] );
} else {
ResNrgPart = 0;
}
} else if( psEncCtrl->ResNrgQ[k] != 0 ) {
if( ResNrgPart > SKP_RSHIFT( SKP_int32_MAX, -psEncCtrl->ResNrgQ[ k ] ) ) {
ResNrgPart = SKP_int32_MAX;
} else {
ResNrgPart = SKP_LSHIFT( ResNrgPart, -psEncCtrl->ResNrgQ[ k ] );
}
}
gain = psEncCtrl->Gains_Q16[ k ];
gain_squared = SKP_ADD_SAT32( ResNrgPart, SKP_SMMUL( gain, gain ) );
if( gain_squared < SKP_int16_MAX ) {
/* recalculate with higher precision */
gain_squared = SKP_SMLAWW( SKP_LSHIFT( ResNrgPart, 16 ), gain, gain );
SKP_assert( gain_squared > 0 );
gain = SKP_Silk_SQRT_APPROX( gain_squared ); /* Q8 */
psEncCtrl->Gains_Q16[ k ] = SKP_LSHIFT_SAT32( gain, 8 ); /* Q16 */
} else {
gain = SKP_Silk_SQRT_APPROX( gain_squared ); /* Q0 */
psEncCtrl->Gains_Q16[ k ] = SKP_LSHIFT_SAT32( gain, 16 ); /* Q16 */
}
}
/* Noise shaping quantization */
SKP_Silk_gains_quant( psEncCtrl->sCmn.GainsIndices, psEncCtrl->Gains_Q16,
&psShapeSt->LastGainIndex, psEnc->sCmn.nFramesInPayloadBuf );
/* Set quantizer offset for voiced signals. Larger offset when LTP coding gain is low or tilt is high (ie low-pass) */
if( psEncCtrl->sCmn.sigtype == SIG_TYPE_VOICED ) {
if( psEncCtrl->LTPredCodGain_Q7 + SKP_RSHIFT( psEncCtrl->input_tilt_Q15, 8 ) > ( 1 << 7 ) ) {
psEncCtrl->sCmn.QuantOffsetType = 0;
} else {
psEncCtrl->sCmn.QuantOffsetType = 1;
}
}
/* Quantizer boundary adjustment */
if( psEncCtrl->sCmn.sigtype == SIG_TYPE_VOICED ) {
psEncCtrl->Lambda_Q10 = SKP_FIX_CONST( 1.3, 10 )
- SKP_SMULWB( SKP_FIX_CONST( 0.5, 18 ), psEnc->speech_activity_Q8 )
- SKP_SMULWB( SKP_FIX_CONST( 0.3, 12 ), psEncCtrl->input_quality_Q14 )
+ SKP_SMULBB( SKP_FIX_CONST( 0.2, 10 ), psEncCtrl->sCmn.QuantOffsetType )
- SKP_SMULWB( SKP_FIX_CONST( 0.1, 12 ), psEncCtrl->coding_quality_Q14 );
} else {
psEncCtrl->Lambda_Q10 = SKP_FIX_CONST( 1.3, 10 )
- SKP_SMULWB( SKP_FIX_CONST( 0.5, 18 ), psEnc->speech_activity_Q8 )
- SKP_SMULWB( SKP_FIX_CONST( 0.4, 12 ), psEncCtrl->input_quality_Q14 )
+ SKP_SMULBB( SKP_FIX_CONST( 0.4, 10 ), psEncCtrl->sCmn.QuantOffsetType )
- SKP_SMULWB( SKP_FIX_CONST( 0.1, 12 ), psEncCtrl->coding_quality_Q14 );
}
SKP_assert( psEncCtrl->Lambda_Q10 >= 0 );
SKP_assert( psEncCtrl->Lambda_Q10 < SKP_FIX_CONST( 2, 10 ) );
}
psEncCtrl->Gains_Q16[ k ] = SKP_LSHIFT_SAT32( tmp32, 16 - Qnrg );
/* Ratio of prediction gains, in energy domain */
SKP_Silk_LPC_inverse_pred_gain_Q13( &pre_nrg_Q30, &psEncCtrl->AR2_Q13[ k * SHAPE_LPC_ORDER_MAX ], psEnc->sCmn.shapingLPCOrder );
SKP_Silk_LPC_inverse_pred_gain_Q13( &nrg, &psEncCtrl->AR1_Q13[ k * SHAPE_LPC_ORDER_MAX ], psEnc->sCmn.shapingLPCOrder );
lz = SKP_min_32( SKP_Silk_CLZ32( pre_nrg_Q30 ) - 1, 19 );
pre_nrg_Q30 = SKP_DIV32( SKP_LSHIFT( pre_nrg_Q30, lz ), SKP_RSHIFT( nrg, 20 - lz ) + 1 ); // Q20
pre_nrg_Q30 = SKP_RSHIFT( SKP_LSHIFT_SAT32( pre_nrg_Q30, 9 ), 1 ); /* Q28 */
psEncCtrl->GainsPre_Q14[ k ] = ( SKP_int )SKP_Silk_SQRT_APPROX( pre_nrg_Q30 );
}
/*****************/
/* Gain tweaking */
/*****************/
/* Increase gains during low speech activity and put lower limit on gains */
gain_mult_Q16 = SKP_Silk_log2lin( -SKP_SMLAWB( -16 << 7, SNR_adj_dB_Q7, 10486 ) ); // 10486_Q16 = 0.16_Q0
gain_add_Q16 = SKP_Silk_log2lin( SKP_SMLAWB( 16 << 7, NOISE_FLOOR_dB_Q7, 10486 ) ); // 10486_Q16 = 0.16_Q0
tmp32 = SKP_Silk_log2lin( SKP_SMLAWB( 16 << 7, RELATIVE_MIN_GAIN_dB_Q7, 10486 ) ); // 10486_Q16 = 0.16_Q0
tmp32 = SKP_SMULWW( psEnc->avgGain_Q16, tmp32 );
gain_add_Q16 = SKP_ADD_SAT32( gain_add_Q16, tmp32 );
SKP_assert( gain_mult_Q16 >= 0 );
for( k = 0; k < NB_SUBFR; k++ ) {
psEncCtrl->Gains_Q16[ k ] = SKP_SMULWW( psEncCtrl->Gains_Q16[ k ], gain_mult_Q16 );
SKP_assert( psEncCtrl->Gains_Q16[ k ] >= 0 );
}
for( k = 0; k < NB_SUBFR; k++ ) {
psEncCtrl->Gains_Q16[ k ] = SKP_ADD_POS_SAT32( psEncCtrl->Gains_Q16[ k ], gain_add_Q16 );
psEnc->avgGain_Q16 = SKP_ADD_SAT32(
psEnc->avgGain_Q16,
