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/* libFLAC - Free Lossless Audio Codec library
* Copyright (C) 2000,2001,2002 Josh Coalson
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
#ifndef FLAC__PRIVATE__LPC_H
#define FLAC__PRIVATE__LPC_H
#include "FLAC/format.h"
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
/*
* 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[], unsigned data_len, unsigned lag, FLAC__real autoc[]);
#ifndef FLAC__NO_ASM
#ifdef FLAC__CPU_IA32
#ifdef FLAC__HAS_NASM
void FLAC__lpc_compute_autocorrelation_asm_ia32(const FLAC__real data[], unsigned data_len, unsigned lag, FLAC__real autoc[]);
void FLAC__lpc_compute_autocorrelation_asm_ia32_sse_lag_4(const FLAC__real data[], unsigned data_len, unsigned lag, FLAC__real autoc[]);
void FLAC__lpc_compute_autocorrelation_asm_ia32_sse_lag_8(const FLAC__real data[], unsigned data_len, unsigned lag, FLAC__real autoc[]);
void FLAC__lpc_compute_autocorrelation_asm_ia32_sse_lag_12(const FLAC__real data[], unsigned data_len, unsigned lag, FLAC__real autoc[]);
void FLAC__lpc_compute_autocorrelation_asm_ia32_3dnow(const FLAC__real data[], unsigned data_len, unsigned lag, FLAC__real autoc[]);
#endif
#endif
#endif
/*
* 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
*
* 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 FLAC__real autoc[], unsigned max_order, FLAC__real lp_coeff[][FLAC__MAX_LPC_ORDER], FLAC__real 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[], unsigned order, unsigned 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[], unsigned data_len, const FLAC__int32 qlp_coeff[], unsigned order, int lp_quantization, FLAC__int32 residual[]);
void FLAC__lpc_compute_residual_from_qlp_coefficients_wide(const FLAC__int32 data[], unsigned data_len, const FLAC__int32 qlp_coeff[], unsigned order, int lp_quantization, FLAC__int32 residual[]);
#ifndef FLAC__NO_ASM
#ifdef FLAC__CPU_IA32
#ifdef FLAC__HAS_NASM
void FLAC__lpc_compute_residual_from_qlp_coefficients_asm_ia32(const FLAC__int32 data[], unsigned data_len, const FLAC__int32 qlp_coeff[], unsigned order, int lp_quantization, FLAC__int32 residual[]);
void FLAC__lpc_compute_residual_from_qlp_coefficients_asm_ia32_mmx(const FLAC__int32 data[], unsigned data_len, const FLAC__int32 qlp_coeff[], unsigned order, int lp_quantization, FLAC__int32 residual[]);
#endif
#endif
#endif
/*
* 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[], unsigned data_len, const FLAC__int32 qlp_coeff[], unsigned order, int lp_quantization, FLAC__int32 data[]);
void FLAC__lpc_restore_signal_wide(const FLAC__int32 residual[], unsigned data_len, const FLAC__int32 qlp_coeff[], unsigned order, int lp_quantization, FLAC__int32 data[]);
#ifndef FLAC__NO_ASM
#ifdef FLAC__CPU_IA32
#ifdef FLAC__HAS_NASM
void FLAC__lpc_restore_signal_asm_ia32(const FLAC__int32 residual[], unsigned data_len, const FLAC__int32 qlp_coeff[], unsigned order, int lp_quantization, FLAC__int32 data[]);
void FLAC__lpc_restore_signal_asm_ia32_mmx(const FLAC__int32 residual[], unsigned data_len, const FLAC__int32 qlp_coeff[], unsigned order, int lp_quantization, FLAC__int32 data[]);
#endif
#endif
#endif
/*
* 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
*/
FLAC__real FLAC__lpc_compute_expected_bits_per_residual_sample(FLAC__real lpc_error, unsigned total_samples);
FLAC__real FLAC__lpc_compute_expected_bits_per_residual_sample_with_error_scale(FLAC__real 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 bits_per_signal_sample # of bits per sample in the original signal
* RETURN [1,max_order] best order
*/
unsigned FLAC__lpc_compute_best_order(const FLAC__real lpc_error[], unsigned max_order, unsigned total_samples, unsigned bits_per_signal_sample);
#endif
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