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/*
* AAC Spectral Band Replication function declarations
* Copyright (c) 2008-2009 Robert Swain ( rob opendot cl )
* Copyright (c) 2010 Alex Converse <alex.converse@gmail.com>
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file
* AAC Spectral Band Replication function declarations
* @author Robert Swain ( rob opendot cl )
*/
#ifndef AVCODEC_AACSBR_H
#define AVCODEC_AACSBR_H
#include "get_bits.h"
#include "aac/aacdec.h"
#include "libavutil/attributes_internal.h"
#define ENVELOPE_ADJUSTMENT_OFFSET 2
#define NOISE_FLOOR_OFFSET 6
/**
* SBR VLC tables
*/
enum {
T_HUFFMAN_ENV_1_5DB,
F_HUFFMAN_ENV_1_5DB,
T_HUFFMAN_ENV_BAL_1_5DB,
F_HUFFMAN_ENV_BAL_1_5DB,
T_HUFFMAN_ENV_3_0DB,
F_HUFFMAN_ENV_3_0DB,
T_HUFFMAN_ENV_BAL_3_0DB,
F_HUFFMAN_ENV_BAL_3_0DB,
T_HUFFMAN_NOISE_3_0DB,
T_HUFFMAN_NOISE_BAL_3_0DB,
};
/**
* bs_frame_class - frame class of current SBR frame (14496-3 sp04 p98)
*/
enum {
FIXFIX,
FIXVAR,
VARFIX,
VARVAR,
};
enum {
EXTENSION_ID_PS = 2,
};
FF_VISIBILITY_PUSH_HIDDEN
/** Initialize SBR. */
void ff_aac_sbr_init(void);
void ff_aac_sbr_init_fixed(void);
/**
* Allocate an ExtChannelElement (if necessary) and
* initialize the SBR context contained in it.
*/
int ff_aac_sbr_ctx_alloc_init(AACDecContext *ac, ChannelElement **che, int id_aac);
int ff_aac_sbr_ctx_alloc_init_fixed(AACDecContext *ac, ChannelElement **che, int id_aac);
/** Close the SBR context implicitly contained in a ChannelElement. */
void ff_aac_sbr_ctx_close(ChannelElement *che);
void ff_aac_sbr_ctx_close_fixed(ChannelElement *che);
/** Decode one SBR element. */
int ff_aac_sbr_decode_extension(AACDecContext *ac, ChannelElement *che,
GetBitContext *gb, int crc, int cnt, int id_aac);
int ff_aac_sbr_decode_extension_fixed(AACDecContext *ac, ChannelElement *che,
GetBitContext *gb, int crc, int cnt, int id_aac);
/** Due to channel allocation not being known upon SBR parameter transmission,
* supply the parameters separately.
* Functionally identical to ff_aac_sbr_decode_extension() */
int ff_aac_sbr_config_usac(AACDecContext *ac, ChannelElement *che,
AACUsacElemConfig *ue);
/** Decode frame SBR data, USAC. */
int ff_aac_sbr_decode_usac_data(AACDecContext *ac, ChannelElement *che,
AACUsacElemConfig *ue, GetBitContext *gb,
int sbr_ch, int indep_flag);
/** Apply one SBR element to one AAC element. */
void ff_aac_sbr_apply(AACDecContext *ac, ChannelElement *che,
int id_aac, void /* float */ *L, void /* float */ *R);
void ff_aac_sbr_apply_fixed(AACDecContext *ac, ChannelElement *che,
int id_aac, void /* int */ *L, void /* int */ *R);
FF_VISIBILITY_POP_HIDDEN
#endif /* AVCODEC_AACSBR_H */