shithub: ft2-clone

ref: f75ed687deda27988f9a566c35efdc074ecf84ed
dir: /src/libflac/private/fixed.h/

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/* libFLAC - Free Lossless Audio Codec library
 * Copyright (C) 2000-2009  Josh Coalson
 * Copyright (C) 2011-2016  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__FIXED_H
#define FLAC__PRIVATE__FIXED_H

#include "../private/float.h"
#include "../FLAC/format.h"

/*
 *	FLAC__fixed_compute_best_predictor()
 *	--------------------------------------------------------------------
 *	Compute the best fixed predictor and the expected bits-per-sample
 *  of the residual signal for each order.  The _wide() version uses
 *  64-bit integers which is statistically necessary when bits-per-
 *  sample + log2(blocksize) > 30
 *
 *	IN data[0,data_len-1]
 *	IN data_len
 *	OUT residual_bits_per_sample[0,FLAC__MAX_FIXED_ORDER]
 */
uint32_t FLAC__fixed_compute_best_predictor(const FLAC__int32 data[], uint32_t data_len, float residual_bits_per_sample[FLAC__MAX_FIXED_ORDER+1]);
uint32_t FLAC__fixed_compute_best_predictor_wide(const FLAC__int32 data[], uint32_t data_len, float residual_bits_per_sample[FLAC__MAX_FIXED_ORDER+1]);

/*
 *	FLAC__fixed_compute_residual()
 *	--------------------------------------------------------------------
 *	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 order <= FLAC__MAX_FIXED_ORDER fixed-predictor order
 *	OUT residual[0,data_len-1]        residual signal
 */
void FLAC__fixed_compute_residual(const FLAC__int32 data[], uint32_t data_len, uint32_t order, FLAC__int32 residual[]);

/*
 *	FLAC__fixed_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 order <= FLAC__MAX_FIXED_ORDER fixed-predictor order
 *	*** 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__fixed_restore_signal(const FLAC__int32 residual[], uint32_t data_len, uint32_t order, FLAC__int32 data[]);

#endif