/* libFLAC - Free Lossless Audio Codec library
* Copyright (C) 2000-2009 Josh Coalson
* Copyright (C) 2011-2025 Xiph.Org Foundation
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* - Neither the name of the Xiph.org Foundation nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#ifndef FLAC__PRIVATE__LPC_H
#define FLAC__PRIVATE__LPC_H
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include "private/cpu.h"
#include "private/float.h"
#include "FLAC/format.h"
#ifndef FLAC__INTEGER_ONLY_LIBRARY
/*
* FLAC__lpc_window_data()
* --------------------------------------------------------------------
* Applies the given window to the data.
* OPT: asm implementation
*
* IN in[0,data_len-1]
* IN window[0,data_len-1]
* OUT out[0,lag-1]
* IN data_len
*/
void FLAC__lpc_window_data(const FLAC__int32 in[], const FLAC__real window[], FLAC__real out[], uint32_t data_len);
void FLAC__lpc_window_data_wide(const FLAC__int64 in[], const FLAC__real window[], FLAC__real out[], uint32_t data_len);
void FLAC__lpc_window_data_partial(const FLAC__int32 in[], const FLAC__real window[], FLAC__real out[], uint32_t data_len, uint32_t part_size, uint32_t data_shift);
void FLAC__lpc_window_data_partial_wide(const FLAC__int64 in[], const FLAC__real window[], FLAC__real out[], uint32_t data_len, uint32_t part_size, uint32_t data_shift);
/*
* FLAC__lpc_compute_autocorrelation()
* --------------------------------------------------------------------
* Compute the autocorrelation for lags between 0 and lag-1.
* Assumes data[] outside of [0,data_len-1] == 0.
* Asserts that lag > 0.
*
* IN data[0,data_len-1]
* IN data_len
* IN 0 < lag <= data_len
* OUT autoc[0,lag-1]
*/
void FLAC__lpc_compute_autocorrelation(const FLAC__real data[], uint32_t data_len, uint32_t lag, double autoc[]);
#ifndef FLAC__NO_ASM
# if (defined FLAC__CPU_IA32 || defined FLAC__CPU_X86_64) && FLAC__HAS_X86INTRIN
# ifdef FLAC__SSE2_SUPPORTED
void FLAC__lpc_compute_autocorrelation_intrin_sse2_lag_8(const FLAC__real data[], uint32_t data_len, uint32_t lag, double autoc[]);
void FLAC__lpc_compute_autocorrelation_intrin_sse2_lag_10(const FLAC__real data[], uint32_t data_len, uint32_t lag, double autoc[]);
void FLAC__lpc_compute_autocorrelation_intrin_sse2_lag_14(const FLAC__real data[], uint32_t data_len, uint32_t lag, double autoc[]);
# endif
# endif
# if defined FLAC__CPU_X86_64 && FLAC__HAS_X86INTRIN
# ifdef FLAC__FMA_SUPPORTED
void FLAC__lpc_compute_autocorrelation_intrin_fma_lag_8(const FLAC__real data[], uint32_t data_len, uint32_t lag, double autoc[]);
void FLAC__lpc_compute_autocorrelation_intrin_fma_lag_12(const FLAC__real data[], uint32_t data_len, uint32_t lag, double autoc[]);
void FLAC__lpc_compute_autocorrelation_intrin_fma_lag_16(const FLAC__real data[], uint32_t data_len, uint32_t lag, double autoc[]);
# endif
# endif
#if defined FLAC__CPU_ARM64 && FLAC__HAS_NEONINTRIN && FLAC__HAS_A64NEONINTRIN
void FLAC__lpc_compute_autocorrelation_intrin_neon_lag_8(const FLAC__real data[], uint32_t data_len, uint32_t lag, double autoc[]);
void FLAC__lpc_compute_autocorrelation_intrin_neon_lag_10(const FLAC__real data[], uint32_t data_len, uint32_t lag, double autoc[]);
void FLAC__lpc_compute_autocorrelation_intrin_neon_lag_14(const FLAC__real data[], uint32_t data_len, uint32_t lag, double autoc[]);
#endif
#endif /* FLAC__NO_ASM */
/*
* FLAC__lpc_compute_lp_coefficients()
* --------------------------------------------------------------------
* Computes LP coefficients for orders 1..max_order.
* Do not call if autoc[0] == 0.0. This means the signal is zero
* and there is no point in calculating a predictor.
*
* IN autoc[0,max_order] autocorrelation values
* IN 0 < max_order <= FLAC__MAX_LPC_ORDER max LP order to compute
* OUT lp_coeff[0,max_order-1][0,max_order-1] LP coefficients for each order
* *** IMPORTANT:
* *** lp_coeff[0,max_order-1][max_order,FLAC__MAX_LPC_ORDER-1] are untouched
* OUT error[0,max_order-1] error for each order (more
* specifically, the variance of
* the error signal times # of
* samples in the signal)
*
* Example: if max_order is 9, the LP coefficients for order 9 will be
* in lp_coeff[8][0,8], the LP coefficients for order 8 will be
* in lp_coeff[7][0,7], etc.
*/
void FLAC__lpc_compute_lp_coefficients(const double autoc[], uint32_t *max_order, FLAC__real lp_coeff[][FLAC__MAX_LPC_ORDER], double error[]);
/*
* FLAC__lpc_quantize_coefficients()
* --------------------------------------------------------------------
* Quantizes the LP coefficients. NOTE: precision + bits_per_sample
* must be less than 32 (sizeof(FLAC__int32)*8).
*
* IN lp_coeff[0,order-1] LP coefficients
* IN order LP order
* IN FLAC__MIN_QLP_COEFF_PRECISION < precision
* desired precision (in bits, including sign
* bit) of largest coefficient
* OUT qlp_coeff[0,order-1] quantized coefficients
* OUT shift # of bits to shift right to get approximated
* LP coefficients. NOTE: could be negative.
* RETURN 0 => quantization OK
* 1 => coefficients require too much shifting for *shift to
* fit in the LPC subframe header. 'shift' is unset.
* 2 => coefficients are all zero, which is bad. 'shift' is
* unset.
*/
int FLAC__lpc_quantize_coefficients(const FLAC__real lp_coeff[], uint32_t order, uint32_t precision, FLAC__int32 qlp_coeff[], int *shift);
/*
* FLAC__lpc_compute_residual_from_qlp_coefficients()
* --------------------------------------------------------------------
* Compute the residual signal obtained from sutracting the predicted
* signal from the original.
*
* IN data[-order,data_len-1] original signal (NOTE THE INDICES!)
* IN data_len length of original signal
* IN qlp_coeff[0,order-1] quantized LP coefficients
* IN order > 0 LP order
* IN lp_quantization quantization of LP coefficients in bits
* OUT residual[0,data_len-1] residual signal
*/
void FLAC__lpc_compute_residual_from_qlp_coefficients(const FLAC__int32 *data, uint32_t data_len, const FLAC__int32 qlp_coeff[], uint32_t order, int lp_quantization, FLAC__int32 residual[]);
void FLAC__lpc_compute_residual_from_qlp_coefficients_wide(const FLAC__int32 *data, uint32_t data_len, const FLAC__int32 qlp_coeff[], uint32_t order, int lp_quantization, FLAC__int32 residual[]);
FLAC__bool FLAC__lpc_compute_residual_from_qlp_coefficients_limit_residual(const FLAC__int32 *data, uint32_t data_len, const FLAC__int32 qlp_coeff[], uint32_t order, int lp_quantization, FLAC__int32 residual[]);
FLAC__bool FLAC__lpc_compute_residual_from_qlp_coefficients_limit_residual_33bit(const FLAC__int64 *data, uint32_t data_len, const FLAC__int32 qlp_coeff[], uint32_t order, int lp_quantization, FLAC__int32 residual[]);
#ifndef FLAC__NO_ASM
# ifdef FLAC__CPU_ARM64
void FLAC__lpc_compute_residual_from_qlp_coefficients_intrin_neon(const FLAC__int32 *data, uint32_t data_len, const FLAC__int32 qlp_coeff[], uint32_t order, int lp_quantization, FLAC__int32 residual[]);
void FLAC__lpc_compute_residual_from_qlp_coefficients_wide_intrin_neon(const FLAC__int32 *data, uint32_t data_len, const FLAC__int32 qlp_coeff[], uint32_t order, int lp_quantization, FLAC__int32 residual[]);
# endif
# if (defined FLAC__CPU_IA32 || defined FLAC__CPU_X86_64) && FLAC__HAS_X86INTRIN
# ifdef FLAC__SSE2_SUPPORTED
void FLAC__lpc_compute_residual_from_qlp_coefficients_16_intrin_sse2(const FLAC__int32 *data, uint32_t data_len, const FLAC__int32 qlp_coeff[], uint32_t order, int lp_quantization, FLAC__int32 residual[]);
void FLAC__lpc_compute_residual_from_qlp_coefficients_intrin_sse2(const FLAC__int32 *data, uint32_t data_len, const FLAC__int32 qlp_coeff[], uint32_t order, int lp_quantization, FLAC__int32 residual[]);
# endif
# ifdef FLAC__SSE4_1_SUPPORTED
void FLAC__lpc_compute_residual_from_qlp_coefficients_intrin_sse41(const FLAC__int32 *data, uint32_t data_len, const FLAC__int32 qlp_coeff[], uint32_t order, int lp_quantization, FLAC__int32 residual[]);
void FLAC__lpc_compute_residual_from_qlp_coefficients_wide_intrin_sse41(const FLAC__int32 *data, uint32_t data_len, const FLAC__int32 qlp_coeff[], uint32_t order, int lp_quantization, FLAC__int32 residual[]);
# endif
# ifdef FLAC__AVX2_SUPPORTED
void FLAC__lpc_compute_residual_from_qlp_coefficients_16_intrin_avx2(const FLAC__int32 *data, uint32_t data_len, const FLAC__int32 qlp_coeff[], uint32_t order, int lp_quantization, FLAC__int32 residual[]);
void FLAC__lpc_compute_residual_from_qlp_coefficients_intrin_avx2(const FLAC__int32 *data, uint32_t data_len, const FLAC__int32 qlp_coeff[], uint32_t order, int lp_quantization, FLAC__int32 residual[]);
void FLAC__lpc_compute_residual_from_qlp_coefficients_wide_intrin_avx2(const FLAC__int32 *data, uint32_t data_len, const FLAC__int32 qlp_coeff[], uint32_t order, int lp_quantization, FLAC__int32 residual[]);
# endif
# endif
#endif
#endif /* !defined FLAC__INTEGER_ONLY_LIBRARY */
FLAC__uint64 FLAC__lpc_max_prediction_value_before_shift(uint32_t subframe_bps, const FLAC__int32 qlp_coeff[], uint32_t order);
uint32_t FLAC__lpc_max_prediction_before_shift_bps(uint32_t subframe_bps, const FLAC__int32 qlp_coeff[], uint32_t order);
uint32_t FLAC__lpc_max_residual_bps(uint32_t subframe_bps, const FLAC__int32 qlp_coeff[], uint32_t order, int lp_quantization);
/*
* FLAC__lpc_restore_signal()
* --------------------------------------------------------------------
* Restore the original signal by summing the residual and the
* predictor.
*
* IN residual[0,data_len-1] residual signal
* IN data_len length of original signal
* IN qlp_coeff[0,order-1] quantized LP coefficients
* IN order > 0 LP order
* IN lp_quantization quantization of LP coefficients in bits
* *** IMPORTANT: the caller must pass in the historical samples:
* IN data[-order,-1] previously-reconstructed historical samples
* OUT data[0,data_len-1] original signal
*/
void FLAC__lpc_restore_signal(const FLAC__int32 residual[], uint32_t data_len, const FLAC__int32 qlp_coeff[], uint32_t order, int lp_quantization, FLAC__int32 data[]);
void FLAC__lpc_restore_signal_wide(const FLAC__int32 residual[], uint32_t data_len, const FLAC__int32 qlp_coeff[], uint32_t order, int lp_quantization, FLAC__int32 data[]);
void FLAC__lpc_restore_signal_wide_33bit(const FLAC__int32 residual[], uint32_t data_len, const FLAC__int32 qlp_coeff[], uint32_t order, int lp_quantization, FLAC__int64 data[]);
#ifndef FLAC__INTEGER_ONLY_LIBRARY
/*
* FLAC__lpc_compute_expected_bits_per_residual_sample()
* --------------------------------------------------------------------
* Compute the expected number of bits per residual signal sample
* based on the LP error (which is related to the residual variance).
*
* IN lpc_error >= 0.0 error returned from calculating LP coefficients
* IN total_samples > 0 # of samples in residual signal
* RETURN expected bits per sample
*/
double FLAC__lpc_compute_expected_bits_per_residual_sample(double lpc_error, uint32_t total_samples);
double FLAC__lpc_compute_expected_bits_per_residual_sample_with_error_scale(double lpc_error, double error_scale);
/*
* FLAC__lpc_compute_best_order()
* --------------------------------------------------------------------
* Compute the best order from the array of signal errors returned
* during coefficient computation.
*
* IN lpc_error[0,max_order-1] >= 0.0 error returned from calculating LP coefficients
* IN max_order > 0 max LP order
* IN total_samples > 0 # of samples in residual signal
* IN overhead_bits_per_order # of bits overhead for each increased LP order
* (includes warmup sample size and quantized LP coefficient)
* RETURN [1,max_order] best order
*/
uint32_t FLAC__lpc_compute_best_order(const double lpc_error[], uint32_t max_order, uint32_t total_samples, uint32_t overhead_bits_per_order);
#endif /* !defined FLAC__INTEGER_ONLY_LIBRARY */
#endif