libavcodec/wma.h

   1 /*
   2  * WMA compatible codec
   3  * Copyright (c) 2002-2007 The FFmpeg Project
   4  *
   5  * This file is part of FFmpeg.
   6  *
   7  * FFmpeg is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2.1 of the License, or (at your option) any later version.
  11  *
  12  * FFmpeg is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with FFmpeg; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 #ifndef AVCODEC_WMA_H
  23 #define AVCODEC_WMA_H
  24
  25 #include "get_bits.h"
  26 #include "put_bits.h"
  27 #include "dsputil.h"
  28
  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 MAX_CHANNELS 2
  45
  46 #define NOISE_TAB_SIZE 8192
  47
  48 #define LSP_POW_BITS 7
  49
  50 //FIXME should be in wmadec
  51 #define VLCBITS 9
  52 #define VLCMAX ((22+VLCBITS-1)/VLCBITS)
  53
  54 typedef float WMACoef;          ///< type for decoded coefficients, int16_t would be enough for wma 1/2
  55
  56 typedef struct CoefVLCTable {
  57     int n;                      ///< total number of codes
  58     int max_level;
  59     const uint32_t *huffcodes;  ///< VLC bit values
  60     const uint8_t *huffbits;    ///< VLC bit size
  61     const uint16_t *levels;     ///< table to build run/level tables
  62 } CoefVLCTable;
  63
  64 typedef struct WMACodecContext {
  65     AVCodecContext* avctx;
  66     GetBitContext gb;
  67     PutBitContext pb;
  68     int sample_rate;
  69     int nb_channels;
  70     int bit_rate;
  71     int version;                            ///< 1 = 0x160 (WMAV1), 2 = 0x161 (WMAV2)
  72     int block_align;
  73     int use_bit_reservoir;
  74     int use_variable_block_len;
  75     int use_exp_vlc;                        ///< exponent coding: 0 = lsp, 1 = vlc + delta
  76     int use_noise_coding;                   ///< true if perceptual noise is added
  77     int byte_offset_bits;
  78     VLC exp_vlc;
  79     int exponent_sizes[BLOCK_NB_SIZES];
  80     uint16_t exponent_bands[BLOCK_NB_SIZES][25];
  81     int high_band_start[BLOCK_NB_SIZES];    ///< index of first coef in high band
  82     int coefs_start;                        ///< first coded coef
  83     int coefs_end[BLOCK_NB_SIZES];          ///< max number of coded coefficients
  84     int exponent_high_sizes[BLOCK_NB_SIZES];
  85     int exponent_high_bands[BLOCK_NB_SIZES][HIGH_BAND_MAX_SIZE];
  86     VLC hgain_vlc;
  87
  88     /* coded values in high bands */
  89     int high_band_coded[MAX_CHANNELS][HIGH_BAND_MAX_SIZE];
  90     int high_band_values[MAX_CHANNELS][HIGH_BAND_MAX_SIZE];
  91
  92     /* there are two possible tables for spectral coefficients */
  93 //FIXME the following 3 tables should be shared between decoders
  94     VLC coef_vlc[2];
  95     uint16_t *run_table[2];
  96     uint16_t *level_table[2];
  97     uint16_t *int_table[2];
  98     const CoefVLCTable *coef_vlcs[2];
  99     /* frame info */
 100     int frame_len;                          ///< frame length in samples
 101     int frame_len_bits;                     ///< frame_len = 1 << frame_len_bits
 102     int nb_block_sizes;                     ///< number of block sizes
 103     /* block info */
 104     int reset_block_lengths;
 105     int block_len_bits;                     ///< log2 of current block length
 106     int next_block_len_bits;                ///< log2 of next block length
 107     int prev_block_len_bits;                ///< log2 of prev block length
 108     int block_len;                          ///< block length in samples
 109     int block_num;                          ///< block number in current frame
 110     int block_pos;                          ///< current position in frame
 111     uint8_t ms_stereo;                      ///< true if mid/side stereo mode
 112     uint8_t channel_coded[MAX_CHANNELS];    ///< true if channel is coded
 113     int exponents_bsize[MAX_CHANNELS];      ///< log2 ratio frame/exp. length
 114     DECLARE_ALIGNED_16(float, exponents[MAX_CHANNELS][BLOCK_MAX_SIZE]);
 115     float max_exponent[MAX_CHANNELS];
 116     WMACoef coefs1[MAX_CHANNELS][BLOCK_MAX_SIZE];
 117     DECLARE_ALIGNED_16(float, coefs[MAX_CHANNELS][BLOCK_MAX_SIZE]);
 118     DECLARE_ALIGNED_16(FFTSample, output[BLOCK_MAX_SIZE * 2]);
 119     MDCTContext mdct_ctx[BLOCK_NB_SIZES];
 120     float *windows[BLOCK_NB_SIZES];
 121     /* output buffer for one frame and the last for IMDCT windowing */
 122     DECLARE_ALIGNED_16(float, frame_out[MAX_CHANNELS][BLOCK_MAX_SIZE * 2]);
 123     /* last frame info */
 124     uint8_t last_superframe[MAX_CODED_SUPERFRAME_SIZE + 4]; /* padding added */
 125     int last_bitoffset;
 126     int last_superframe_len;
 127     float noise_table[NOISE_TAB_SIZE];
 128     int noise_index;
 129     float noise_mult; /* XXX: suppress that and integrate it in the noise array */
 130     /* lsp_to_curve tables */
 131     float lsp_cos_table[BLOCK_MAX_SIZE];
 132     float lsp_pow_e_table[256];
 133     float lsp_pow_m_table1[(1 << LSP_POW_BITS)];
 134     float lsp_pow_m_table2[(1 << LSP_POW_BITS)];
 135     DSPContext dsp;
 136
 137 #ifdef TRACE
 138     int frame_count;
 139 #endif
 140 } WMACodecContext;
 141
 142 extern const uint16_t ff_wma_hgain_huffcodes[37];
 143 extern const uint8_t ff_wma_hgain_huffbits[37];
 144 extern const float ff_wma_lsp_codebook[NB_LSP_COEFS][16];
 145 extern const uint32_t ff_wma_scale_huffcodes[121];
 146 extern const uint8_t ff_wma_scale_huffbits[121];
 147
 148 int av_cold ff_wma_get_frame_len_bits(int sample_rate, int version,
 149                                       unsigned int decode_flags);
 150 int ff_wma_init(AVCodecContext * avctx, int flags2);
 151 int ff_wma_total_gain_to_bits(int total_gain);
 152 int ff_wma_end(AVCodecContext *avctx);
 153 unsigned int ff_wma_get_large_val(GetBitContext* gb);
 154 int ff_wma_run_level_decode(AVCodecContext* avctx, GetBitContext* gb,
 155                             VLC *vlc,
 156                             const uint16_t *level_table, const uint16_t *run_table,
 157                             int version, WMACoef *ptr, int offset,
 158                             int num_coefs, int block_len, int frame_len_bits,
 159                             int coef_nb_bits);
 160
 161 #endif /* AVCODEC_WMA_H */