mpeg4audio.h

/*
 * MPEG-4 Audio common header
 * Copyright (c) 2008 Baptiste Coudurier <baptiste.coudurier@free.fr>
 *
 * 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
 */

#ifndef AVCODEC_MPEG4AUDIO_H
#define AVCODEC_MPEG4AUDIO_H

#include <stdint.h>

#include "libavutil/attributes.h"

#include "get_bits.h"
#include "internal.h"
#include "put_bits.h"

typedef struct MPEG4AudioConfig {
    int object_type;
    int sampling_index;
    int sample_rate;
    int chan_config;
    int sbr; 
    int ext_object_type;
    int ext_sampling_index;
    int ext_sample_rate;
    int ext_chan_config;
    int channels;
    int ps;  
    int frame_length_short;
} MPEG4AudioConfig;

extern av_export_avcodec const int avpriv_mpeg4audio_sample_rates[16];
extern const uint8_t ff_mpeg4audio_channels[8];

int ff_mpeg4audio_get_config_gb(MPEG4AudioConfig *c, GetBitContext *gb,
                                int sync_extension);

int avpriv_mpeg4audio_get_config(MPEG4AudioConfig *c, const uint8_t *buf,
                                 int bit_size, int sync_extension);

enum AudioObjectType {
    AOT_NULL,
                               // Support?                Name
    AOT_AAC_MAIN,              
    AOT_AAC_LC,                
    AOT_AAC_SSR,               
    AOT_AAC_LTP,               
    AOT_SBR,                   
    AOT_AAC_SCALABLE,          
    AOT_TWINVQ,                
    AOT_CELP,                  
    AOT_HVXC,                  
    AOT_TTSI             = 12, 
    AOT_MAINSYNTH,             
    AOT_WAVESYNTH,             
    AOT_MIDI,                  
    AOT_SAFX,                  
    AOT_ER_AAC_LC,             
    AOT_ER_AAC_LTP       = 19, 
    AOT_ER_AAC_SCALABLE,       
    AOT_ER_TWINVQ,             
    AOT_ER_BSAC,               
    AOT_ER_AAC_LD,             
    AOT_ER_CELP,               
    AOT_ER_HVXC,               
    AOT_ER_HILN,               
    AOT_ER_PARAM,              
    AOT_SSC,                   
    AOT_PS,                    
    AOT_SURROUND,              
    AOT_ESCAPE,                
    AOT_L1,                    
    AOT_L2,                    
    AOT_L3,                    
    AOT_DST,                   
    AOT_ALS,                   
    AOT_SLS,                   
    AOT_SLS_NON_CORE,          
    AOT_ER_AAC_ELD,            
    AOT_SMR_SIMPLE,            
    AOT_SMR_MAIN,              
    AOT_USAC_NOSBR,            
    AOT_SAOC,                  
    AOT_LD_SURROUND,           
    AOT_USAC,                  
};

#define MAX_PCE_SIZE 320 

static av_always_inline unsigned int ff_pce_copy_bits(PutBitContext *pb,
                                                      GetBitContext *gb,
                                                      int bits)
{
    unsigned int el = get_bits(gb, bits);
    put_bits(pb, bits, el);
    return el;
}

static inline int ff_copy_pce_data(PutBitContext *pb, GetBitContext *gb)
{
    int five_bit_ch, four_bit_ch, comment_size, bits;
    int offset = put_bits_count(pb);

    ff_pce_copy_bits(pb, gb, 10);               // Tag, Object Type, Frequency
    five_bit_ch  = ff_pce_copy_bits(pb, gb, 4); // Front
    five_bit_ch += ff_pce_copy_bits(pb, gb, 4); // Side
    five_bit_ch += ff_pce_copy_bits(pb, gb, 4); // Back
    four_bit_ch  = ff_pce_copy_bits(pb, gb, 2); // LFE
    four_bit_ch += ff_pce_copy_bits(pb, gb, 3); // Data
    five_bit_ch += ff_pce_copy_bits(pb, gb, 4); // Coupling
    if (ff_pce_copy_bits(pb, gb, 1))            // Mono Mixdown
        ff_pce_copy_bits(pb, gb, 4);
    if (ff_pce_copy_bits(pb, gb, 1))            // Stereo Mixdown
        ff_pce_copy_bits(pb, gb, 4);
    if (ff_pce_copy_bits(pb, gb, 1))            // Matrix Mixdown
        ff_pce_copy_bits(pb, gb, 3);
    for (bits = five_bit_ch*5+four_bit_ch*4; bits > 16; bits -= 16)
        ff_pce_copy_bits(pb, gb, 16);
    if (bits)
        ff_pce_copy_bits(pb, gb, bits);
    avpriv_align_put_bits(pb);
    align_get_bits(gb);
    comment_size = ff_pce_copy_bits(pb, gb, 8);
    for (; comment_size > 0; comment_size--)
        ff_pce_copy_bits(pb, gb, 8);

    return put_bits_count(pb) - offset;
}

#endif /* AVCODEC_MPEG4AUDIO_H */