Exemplo n.º 1
0
/* 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 ) );
}
Exemplo n.º 6
0
/* 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;
}
Exemplo n.º 7
0
/* 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 );
}
Exemplo n.º 8
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 ) );
}
Exemplo n.º 9
0
/* 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));

}
Exemplo n.º 11
0
/* 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 ) );
    }
}