/* Processing of gains */
internal static void silk_process_gains(
SilkChannelEncoder psEnc, /* I/O Encoder state */
SilkEncoderControl psEncCtrl, /* I/O Encoder control */
int condCoding /* I The type of conditional coding to use */
)
{
SilkShapeState psShapeSt = psEnc.sShape;
int k;
int s_Q16, InvMaxSqrVal_Q16, gain, gain_squared, ResNrg, ResNrgPart, quant_offset_Q10;
/* Gain reduction when LTP coding gain is high */
if (psEnc.indices.signalType == SilkConstants.TYPE_VOICED)
{
/*s = -0.5f * silk_sigmoid( 0.25f * ( psEncCtrl.LTPredCodGain - 12.0f ) ); */
s_Q16 = 0 - Sigmoid.silk_sigm_Q15(Inlines.silk_RSHIFT_ROUND(psEncCtrl.LTPredCodGain_Q7 - ((int)((12.0f) * ((long)1 << (7)) + 0.5)) /*Inlines.SILK_CONST(12.0f, 7)*/, 4));
for (k = 0; k < psEnc.nb_subfr; k++)
{
psEncCtrl.Gains_Q16[k] = Inlines.silk_SMLAWB(psEncCtrl.Gains_Q16[k], psEncCtrl.Gains_Q16[k], s_Q16);
}
}
/* Limit the quantized signal */
/* InvMaxSqrVal = pow( 2.0f, 0.33f * ( 21.0f - SNR_dB ) ) / subfr_length; */
InvMaxSqrVal_Q16 = Inlines.silk_DIV32_16(Inlines.silk_log2lin(
Inlines.silk_SMULWB(((int)((21 + 16 / 0.33f) * ((long)1 << (7)) + 0.5)) /*Inlines.SILK_CONST(21 + 16 / 0.33f, 7)*/ - psEnc.SNR_dB_Q7, ((int)((0.33f) * ((long)1 << (16)) + 0.5)) /*Inlines.SILK_CONST(0.33f, 16)*/)), psEnc.subfr_length);
for (k = 0; k < psEnc.nb_subfr; k++)
{
/* Soft limit on ratio residual energy and squared gains */
ResNrg = psEncCtrl.ResNrg[k];
ResNrgPart = Inlines.silk_SMULWW(ResNrg, InvMaxSqrVal_Q16);
if (psEncCtrl.ResNrgQ[k] > 0)
{
ResNrgPart = Inlines.silk_RSHIFT_ROUND(ResNrgPart, psEncCtrl.ResNrgQ[k]);
}
else
{
if (ResNrgPart >= Inlines.silk_RSHIFT(int.MaxValue, -psEncCtrl.ResNrgQ[k]))
{
ResNrgPart = int.MaxValue;
}
else
{
ResNrgPart = Inlines.silk_LSHIFT(ResNrgPart, -psEncCtrl.ResNrgQ[k]);
}
}
gain = psEncCtrl.Gains_Q16[k];
gain_squared = Inlines.silk_ADD_SAT32(ResNrgPart, Inlines.silk_SMMUL(gain, gain));
if (gain_squared < short.MaxValue)
{
/* recalculate with higher precision */
gain_squared = Inlines.silk_SMLAWW(Inlines.silk_LSHIFT(ResNrgPart, 16), gain, gain);
Inlines.OpusAssert(gain_squared > 0);
gain = Inlines.silk_SQRT_APPROX(gain_squared); /* Q8 */
gain = Inlines.silk_min(gain, int.MaxValue >> 8);
psEncCtrl.Gains_Q16[k] = Inlines.silk_LSHIFT_SAT32(gain, 8); /* Q16 */
}
else
{
gain = Inlines.silk_SQRT_APPROX(gain_squared); /* Q0 */
gain = Inlines.silk_min(gain, int.MaxValue >> 16);
psEncCtrl.Gains_Q16[k] = Inlines.silk_LSHIFT_SAT32(gain, 16); /* Q16 */
}
}
/* Save unquantized gains and gain Index */
Array.Copy(psEncCtrl.Gains_Q16, psEncCtrl.GainsUnq_Q16, psEnc.nb_subfr);
psEncCtrl.lastGainIndexPrev = psShapeSt.LastGainIndex;
/* Quantize gains */
BoxedValueSbyte boxed_lastGainIndex = new BoxedValueSbyte(psShapeSt.LastGainIndex);
GainQuantization.silk_gains_quant(psEnc.indices.GainsIndices, psEncCtrl.Gains_Q16,
boxed_lastGainIndex, condCoding == SilkConstants.CODE_CONDITIONALLY ? 1 : 0, psEnc.nb_subfr);
psShapeSt.LastGainIndex = boxed_lastGainIndex.Val;
/* Set quantizer offset for voiced signals. Larger offset when LTP coding gain is low or tilt is high (ie low-pass) */
if (psEnc.indices.signalType == SilkConstants.TYPE_VOICED)
{
if (psEncCtrl.LTPredCodGain_Q7 + Inlines.silk_RSHIFT(psEnc.input_tilt_Q15, 8) > ((int)((1.0f) * ((long)1 << (7)) + 0.5)) /*Inlines.SILK_CONST(1.0f, 7)*/)
{
psEnc.indices.quantOffsetType = 0;
}
else
{
psEnc.indices.quantOffsetType = 1;
}
}
/* Quantizer boundary adjustment */
quant_offset_Q10 = Tables.silk_Quantization_Offsets_Q10[psEnc.indices.signalType >> 1][psEnc.indices.quantOffsetType];
psEncCtrl.Lambda_Q10 = ((int)((TuningParameters.LAMBDA_OFFSET) * ((long)1 << (10)) + 0.5))/*Inlines.SILK_CONST(TuningParameters.LAMBDA_OFFSET, 10)*/
+ Inlines.silk_SMULBB(((int)((TuningParameters.LAMBDA_DELAYED_DECISIONS) * ((long)1 << (10)) + 0.5)) /*Inlines.SILK_CONST(TuningParameters.LAMBDA_DELAYED_DECISIONS, 10)*/, psEnc.nStatesDelayedDecision)
+ Inlines.silk_SMULWB(((int)((TuningParameters.LAMBDA_SPEECH_ACT) * ((long)1 << (18)) + 0.5)) /*Inlines.SILK_CONST(TuningParameters.LAMBDA_SPEECH_ACT, 18)*/, psEnc.speech_activity_Q8)
+ Inlines.silk_SMULWB(((int)((TuningParameters.LAMBDA_INPUT_QUALITY) * ((long)1 << (12)) + 0.5)) /*Inlines.SILK_CONST(TuningParameters.LAMBDA_INPUT_QUALITY, 12)*/, psEncCtrl.input_quality_Q14)
+ Inlines.silk_SMULWB(((int)((TuningParameters.LAMBDA_CODING_QUALITY) * ((long)1 << (12)) + 0.5)) /*Inlines.SILK_CONST(TuningParameters.LAMBDA_CODING_QUALITY, 12)*/, psEncCtrl.coding_quality_Q14)
+ Inlines.silk_SMULWB(((int)((TuningParameters.LAMBDA_QUANT_OFFSET) * ((long)1 << (16)) + 0.5)) /*Inlines.SILK_CONST(TuningParameters.LAMBDA_QUANT_OFFSET, 16)*/, quant_offset_Q10);
Inlines.OpusAssert(psEncCtrl.Lambda_Q10 > 0);
Inlines.OpusAssert(psEncCtrl.Lambda_Q10 < ((int)((2) * ((long)1 << (10)) + 0.5)) /*Inlines.SILK_CONST(2, 10)*/);
}
/* Decode parameters from payload */
internal static void silk_decode_parameters(
SilkChannelDecoder psDec, /* I/O State */
SilkDecoderControl psDecCtrl, /* I/O Decoder control */
int condCoding /* I The type of conditional coding to use */
)
{
int i, k, Ix;
short[] pNLSF_Q15 = new short[psDec.LPC_order];
short[] pNLSF0_Q15 = new short[psDec.LPC_order];
sbyte[][] cbk_ptr_Q7;
/* Dequant Gains */
BoxedValueSbyte boxedLastGainIndex = new BoxedValueSbyte(psDec.LastGainIndex);
GainQuantization.silk_gains_dequant(psDecCtrl.Gains_Q16, psDec.indices.GainsIndices,
boxedLastGainIndex, condCoding == SilkConstants.CODE_CONDITIONALLY ? 1 : 0, psDec.nb_subfr);
psDec.LastGainIndex = boxedLastGainIndex.Val;
/****************/
/* Decode NLSFs */
/****************/
NLSF.silk_NLSF_decode(pNLSF_Q15, psDec.indices.NLSFIndices, psDec.psNLSF_CB);
/* Convert NLSF parameters to AR prediction filter coefficients */
NLSF.silk_NLSF2A(psDecCtrl.PredCoef_Q12[1], pNLSF_Q15, psDec.LPC_order);
/* If just reset, e.g., because internal Fs changed, do not allow interpolation */
/* improves the case of packet loss in the first frame after a switch */
if (psDec.first_frame_after_reset == 1)
{
psDec.indices.NLSFInterpCoef_Q2 = 4;
}
if (psDec.indices.NLSFInterpCoef_Q2 < 4)
{
/* Calculation of the interpolated NLSF0 vector from the interpolation factor, */
/* the previous NLSF1, and the current NLSF1 */
for (i = 0; i < psDec.LPC_order; i++)
{
pNLSF0_Q15[i] = (short)(psDec.prevNLSF_Q15[i] + Inlines.silk_RSHIFT(Inlines.silk_MUL(psDec.indices.NLSFInterpCoef_Q2,
pNLSF_Q15[i] - psDec.prevNLSF_Q15[i]), 2));
}
/* Convert NLSF parameters to AR prediction filter coefficients */
NLSF.silk_NLSF2A(psDecCtrl.PredCoef_Q12[0], pNLSF0_Q15, psDec.LPC_order);
}
else
{
/* Copy LPC coefficients for first half from second half */
Array.Copy(psDecCtrl.PredCoef_Q12[1], psDecCtrl.PredCoef_Q12[0], psDec.LPC_order);
}
Array.Copy(pNLSF_Q15, psDec.prevNLSF_Q15, psDec.LPC_order);
/* After a packet loss do BWE of LPC coefs */
if (psDec.lossCnt != 0)
{
BWExpander.silk_bwexpander(psDecCtrl.PredCoef_Q12[0], psDec.LPC_order, SilkConstants.BWE_AFTER_LOSS_Q16);
BWExpander.silk_bwexpander(psDecCtrl.PredCoef_Q12[1], psDec.LPC_order, SilkConstants.BWE_AFTER_LOSS_Q16);
}
if (psDec.indices.signalType == SilkConstants.TYPE_VOICED)
{
/*********************/
/* Decode pitch lags */
/*********************/
/* Decode pitch values */
DecodePitch.silk_decode_pitch(psDec.indices.lagIndex, psDec.indices.contourIndex, psDecCtrl.pitchL, psDec.fs_kHz, psDec.nb_subfr);
/* Decode Codebook Index */
cbk_ptr_Q7 = Tables.silk_LTP_vq_ptrs_Q7[psDec.indices.PERIndex]; /* set pointer to start of codebook */
for (k = 0; k < psDec.nb_subfr; k++)
{
Ix = psDec.indices.LTPIndex[k];
for (i = 0; i < SilkConstants.LTP_ORDER; i++)
{
psDecCtrl.LTPCoef_Q14[k * SilkConstants.LTP_ORDER + i] = (short)(Inlines.silk_LSHIFT(cbk_ptr_Q7[Ix][i], 7));
}
}
/**********************/
/* Decode LTP scaling */
/**********************/
Ix = psDec.indices.LTP_scaleIndex;
psDecCtrl.LTP_scale_Q14 = Tables.silk_LTPScales_table_Q14[Ix];
}
else
{
Arrays.MemSetInt(psDecCtrl.pitchL, 0, psDec.nb_subfr);
Arrays.MemSetShort(psDecCtrl.LTPCoef_Q14, 0, SilkConstants.LTP_ORDER * psDec.nb_subfr);
psDec.indices.PERIndex = 0;
psDecCtrl.LTP_scale_Q14 = 0;
}
}
