apps/codecs/libwma/wmadec.h

   1 /*
   2  * WMA compatible decoder
   3  * Copyright (c) 2002 The FFmpeg Project.
   4  *
   5  * This library is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU Lesser General Public
   7  * License as published by the Free Software Foundation; either
   8  * version 2 of the License, or (at your option) any later version.
   9  *
  10  * This library is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * Lesser General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU Lesser General Public
  16  * License along with this library; if not, write to the Free Software
  17  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  18  */
  19
  20 #ifndef _WMADEC_H
  21 #define _WMADEC_H
  22
  23 #include "asf.h"
  24 #include "bitstream.h" /* For GetBitContext */
  25 //#include "dsputil.h"  /* For MDCTContext */
  26
  27
  28 //#define TRACE
  29 /* size of blocks */
  30 #define BLOCK_MIN_BITS 7
  31 #define BLOCK_MAX_BITS 11
  32 #define BLOCK_MAX_SIZE (1 << BLOCK_MAX_BITS)
  33
  34 #define BLOCK_NB_SIZES (BLOCK_MAX_BITS - BLOCK_MIN_BITS + 1)
  35
  36 /* XXX: find exact max size */
  37 #define HIGH_BAND_MAX_SIZE 16
  38
  39 #define NB_LSP_COEFS 10
  40
  41 /* XXX: is it a suitable value ? */
  42 #define MAX_CODED_SUPERFRAME_SIZE 16384
  43
  44 #define M_PI    3.14159265358979323846
  45
  46 #define M_PI_F  0x3243f // in fixed 32 format
  47 #define TWO_M_PI_F  0x6487f   //in fixed 32
  48
  49 #define MAX_CHANNELS 2
  50
  51 #define NOISE_TAB_SIZE 8192
  52
  53 #define LSP_POW_BITS 7
  54
  55 #define fixed32         int32_t
  56 #define fixed64         int64_t
  57
  58 typedef fixed32 FFTSample;
  59
  60 typedef struct FFTComplex
  61 {
  62     fixed32 re, im;
  63 }
  64 FFTComplex;
  65
  66 typedef struct FFTContext
  67 {
  68     int nbits;
  69     int inverse;
  70     uint16_t *revtab;
  71     FFTComplex *exptab;
  72     FFTComplex *exptab1; /* only used by SSE code */
  73     int (*fft_calc)(struct FFTContext *s, FFTComplex *z);
  74 }
  75 FFTContext;
  76
  77 typedef struct MDCTContext
  78 {
  79     int n;  /* size of MDCT (i.e. number of input data * 2) */
  80     int nbits; /* n = 2^nbits */
  81     /* pre/post rotation tables */
  82     fixed32 *tcos;
  83     fixed32 *tsin;
  84     FFTContext fft;
  85 }
  86 MDCTContext;
  87
  88 typedef struct WMADecodeContext
  89 {
  90     GetBitContext gb;
  91
  92     int nb_block_sizes;  /* number of block sizes */
  93
  94     int sample_rate;
  95     int nb_channels;
  96     int bit_rate;
  97     int version; /* 1 = 0x160 (WMAV1), 2 = 0x161 (WMAV2) */
  98     int block_align;
  99     int use_bit_reservoir;
 100     int use_variable_block_len;
 101     int use_exp_vlc;  /* exponent coding: 0 = lsp, 1 = vlc + delta */
 102     int use_noise_coding; /* true if perceptual noise is added */
 103     int byte_offset_bits;
 104     VLC exp_vlc;
 105     int exponent_sizes[BLOCK_NB_SIZES];
 106     uint16_t exponent_bands[BLOCK_NB_SIZES][25];
 107     int high_band_start[BLOCK_NB_SIZES]; /* index of first coef in high band */
 108     int coefs_start;               /* first coded coef */
 109     int coefs_end[BLOCK_NB_SIZES]; /* max number of coded coefficients */
 110     int exponent_high_sizes[BLOCK_NB_SIZES];
 111     int exponent_high_bands[BLOCK_NB_SIZES][HIGH_BAND_MAX_SIZE];
 112     VLC hgain_vlc;
 113
 114     /* coded values in high bands */
 115     int high_band_coded[MAX_CHANNELS][HIGH_BAND_MAX_SIZE];
 116     int high_band_values[MAX_CHANNELS][HIGH_BAND_MAX_SIZE];
 117
 118     /* there are two possible tables for spectral coefficients */
 119     VLC coef_vlc[2];
 120     uint16_t *run_table[2];
 121     uint16_t *level_table[2];
 122     /* frame info */
 123     int frame_len;       /* frame length in samples */
 124     int frame_len_bits;  /* frame_len = 1 << frame_len_bits */
 125
 126     /* block info */
 127     int reset_block_lengths;
 128     int block_len_bits; /* log2 of current block length */
 129     int next_block_len_bits; /* log2 of next block length */
 130     int prev_block_len_bits; /* log2 of prev block length */
 131     int block_len; /* block length in samples */
 132     int block_num; /* block number in current frame */
 133     int block_pos; /* current position in frame */
 134     uint8_t ms_stereo; /* true if mid/side stereo mode */
 135     uint8_t channel_coded[MAX_CHANNELS]; /* true if channel is coded */
 136     int exponents_bsize[MAX_CHANNELS];      // log2 ratio frame/exp. length
 137     fixed32 exponents[MAX_CHANNELS][BLOCK_MAX_SIZE];
 138     fixed32 max_exponent[MAX_CHANNELS];
 139     int16_t coefs1[MAX_CHANNELS][BLOCK_MAX_SIZE];
 140     fixed32 (*coefs)[MAX_CHANNELS][BLOCK_MAX_SIZE];
 141     MDCTContext mdct_ctx[BLOCK_NB_SIZES];
 142     fixed32 *windows[BLOCK_NB_SIZES];
 143     FFTComplex *mdct_tmp; /* temporary storage for imdct */
 144     /* output buffer for one frame and the last for IMDCT windowing */
 145     fixed32 frame_out[MAX_CHANNELS][BLOCK_MAX_SIZE * 2];
 146     /* last frame info */
 147     uint8_t last_superframe[MAX_CODED_SUPERFRAME_SIZE + 4]; /* padding added */
 148     int last_bitoffset;
 149     int last_superframe_len;
 150     fixed32 *noise_table;
 151     int noise_index;
 152     fixed32 noise_mult; /* XXX: suppress that and integrate it in the noise array */
 153     /* lsp_to_curve tables */
 154     fixed32 lsp_cos_table[BLOCK_MAX_SIZE];
 155     fixed64 lsp_pow_e_table[256];
 156     fixed32 lsp_pow_m_table1[(1 << LSP_POW_BITS)];
 157     fixed32 lsp_pow_m_table2[(1 << LSP_POW_BITS)];
 158
 159     /* State of current superframe decoding */
 160     int bit_offset;
 161     int nb_frames;
 162     int current_frame;
 163
 164 #ifdef TRACE
 165
 166     int frame_count;
 167 #endif
 168 }
 169 WMADecodeContext;
 170
 171 int wma_decode_init(WMADecodeContext* s, asf_waveformatex_t *wfx);
 172 int wma_decode_superframe_init(WMADecodeContext* s,
 173                                uint8_t *buf, int buf_size);
 174 int wma_decode_superframe_frame(WMADecodeContext* s,
 175                                 int32_t *samples,
 176                                 uint8_t *buf, int buf_size);
 177 #endif