mpeg3audio.h

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/**********************************************************************
** Copyright (C) 2000 Trolltech AS.  All rights reserved.
**
** This file is part of Qtopia Environment.
**
** This file may be distributed and/or modified under the terms of the
** GNU General Public License version 2 as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL included in the
** packaging of this file.
**
** This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
** WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
**
** See http://www.trolltech.com/gpl/ for GPL licensing information.
**
** Contact info@trolltech.com if any conditions of this licensing are
** not clear to you.
**
**********************************************************************/
#ifndef MPEG3AUDIO_H
#define MPEG3AUDIO_H

#include "ac3.h"
#include "../bitstream.h"
typedef struct mpeg3_atrack_rec mpeg3_atrack_t;

#define MAXFRAMESIZE 1792
#define HDRCMPMASK 0xfffffd00
#define SBLIMIT 32
#define SSLIMIT 18
#define SCALE_BLOCK 12
#define MPEG3AUDIO_PADDING 1024

/* Values for mode */
#define MPG_MD_STEREO                   0
#define MPG_MD_JOINT_STEREO     1
#define MPG_MD_DUAL_CHANNEL     2
#define MPG_MD_MONO                     3

/* IMDCT variables */
typedef struct
{
        mpeg3_real_t real;
        mpeg3_real_t imag;
} mpeg3_complex_t;

#define AC3_N 512

struct al_table 
{
        short bits;
        short d;
};

typedef struct
{
        struct mpeg3_rec* file;
        mpeg3_atrack_t* track;
        mpeg3_bits_t *astream;

/* In order of importance */
        int format;               /* format of audio */
        int layer;                /* layer if mpeg */
        int channels;
        long outscale;
        long framenum;
        long prev_framesize;
        long framesize;           /* For mp3 current framesize without header.  For AC3 current framesize with header. */
        int avg_framesize;      /* Includes the 4 byte header */
        mpeg3_real_t *pcm_sample;        /* Interlaced output from synthesizer in floats */
        int pcm_point;            /* Float offset in pcm_sample to write to */
        long pcm_position;        /* Sample start of pcm_samples in file */
        long pcm_size;            /* Number of pcm samples in the buffer */
        long pcm_allocated;       /* Allocated number of samples in pcm_samples */
        int sample_seek;
        double percentage_seek;
        unsigned long oldhead;
        unsigned long newhead;
        unsigned long firsthead;
        int bsnum;
        int lsf;
        int mpeg35;
        int sampling_frequency_code;
        int bitrate_index;
        int bitrate;
        int samples_per_frame;
        int padding;
        int extension;
        int mode;
        int mode_ext;
        int copyright;
        int original;
        int emphasis;
        int error_protection;

/* Back step buffers for mp3 */
        unsigned char bsspace[2][MAXFRAMESIZE + 512]; /* MAXFRAMESIZE */
        unsigned char *bsbuf, *bsbufold;
        long ssize;
        int init;
        int single;
    struct al_table *alloc;
    int II_sblimit;
    int jsbound;
        int bo;                      /* Static variable in synthesizer */

/* MP3 Static arrays here */
        mpeg3_real_t synth_stereo_buffs[2][2][0x110];
        mpeg3_real_t synth_mono_buff[64];
        unsigned int layer2_scfsi_buf[64];

        mpeg3_real_t mp3_block[2][2][SBLIMIT * SSLIMIT];
        int mp3_blc[2];

/* AC3 specific stuff.  AC3 also shares objects with MPEG */
        unsigned int ac3_framesize_code;
        mpeg3_ac3bsi_t ac3_bsi;
        mpeg3_ac3audblk_t ac3_audblk;
        mpeg3_ac3_bitallocation_t ac3_bit_allocation;
        mpeg3_ac3_mantissa_t ac3_mantissa;
        mpeg3_complex_t ac3_imdct_buf[AC3_N / 4];

/* Delay buffer for DCT interleaving */
        mpeg3_real_t ac3_delay[6][AC3_N / 2];
/* Twiddle factor LUT */
        mpeg3_complex_t *ac3_w[7];
#if !defined(USE_FIXED_POINT) || defined(PRINT_FIXED_POINT_TABLES)
        /* Just for allocated memory */
        mpeg3_complex_t ac3_w_1[1];
        mpeg3_complex_t ac3_w_2[2];
        mpeg3_complex_t ac3_w_4[4];
        mpeg3_complex_t ac3_w_8[8];
        mpeg3_complex_t ac3_w_16[16];
        mpeg3_complex_t ac3_w_32[32];
        mpeg3_complex_t ac3_w_64[64];
#endif
        int ac3_lfsr_state;
        unsigned char ac3_buffer[MAX_AC3_FRAMESIZE];
        mpeg3ac3_stream_samples_t ac3_samples;
} mpeg3audio_t;



#endif

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