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//#ifdef HAVE_CONFIG_H
#include "../config.h"
//#endif
#ifdef FIXED_POINT
#include "fixed/main_FIX.h"
#else
#include "main_FLP.h"
#endif
#include "tuning_parameters.h"

/* High-pass filter with cutoff frequency adaptation based on pitch lag statistics */
void silk_HP_variable_cutoff(
    silk_encoder_state_Fxx          state_Fxx[]                         /* I/O  Encoder states                              */
) {
    opus_int   quality_Q15;
    opus_int32 pitch_freq_Hz_Q16, pitch_freq_log_Q7, delta_freq_Q7;
    silk_encoder_state *psEncC1 = &state_Fxx[ 0 ].sCmn;

    /* Adaptive cutoff frequency: estimate low end of pitch frequency range */
    if (psEncC1->prevSignalType == TYPE_VOICED) {
        /* difference, in log domain */
        pitch_freq_Hz_Q16 = silk_DIV32_16(silk_LSHIFT(silk_MUL(psEncC1->fs_kHz, 1000), 16), psEncC1->prevLag);
        pitch_freq_log_Q7 = silk_lin2log(pitch_freq_Hz_Q16) - (16 << 7);

        /* adjustment based on quality */
        quality_Q15 = psEncC1->input_quality_bands_Q15[ 0 ];
        pitch_freq_log_Q7 = silk_SMLAWB(pitch_freq_log_Q7, silk_SMULWB(silk_LSHIFT(-quality_Q15, 2), quality_Q15),
                                        pitch_freq_log_Q7 - (silk_lin2log(SILK_FIX_CONST(VARIABLE_HP_MIN_CUTOFF_HZ, 16)) - (16 << 7)));

        /* delta_freq = pitch_freq_log - psEnc->variable_HP_smth1; */
        delta_freq_Q7 = pitch_freq_log_Q7 - silk_RSHIFT(psEncC1->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 = silk_MUL(delta_freq_Q7, 3);
        }

        /* limit delta, to reduce impact of outliers in pitch estimation */
        delta_freq_Q7 = silk_LIMIT_32(delta_freq_Q7, -SILK_FIX_CONST(VARIABLE_HP_MAX_DELTA_FREQ, 7), SILK_FIX_CONST(VARIABLE_HP_MAX_DELTA_FREQ, 7));

        /* update smoother */
        psEncC1->variable_HP_smth1_Q15 = silk_SMLAWB(psEncC1->variable_HP_smth1_Q15,
                                         silk_SMULBB(psEncC1->speech_activity_Q8, delta_freq_Q7), SILK_FIX_CONST(VARIABLE_HP_SMTH_COEF1, 16));

        /* limit frequency range */
        psEncC1->variable_HP_smth1_Q15 = silk_LIMIT_32(psEncC1->variable_HP_smth1_Q15,
                                         silk_LSHIFT(silk_lin2log(VARIABLE_HP_MIN_CUTOFF_HZ), 8),
                                         silk_LSHIFT(silk_lin2log(VARIABLE_HP_MAX_CUTOFF_HZ), 8));
    }
}
