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 "libavutil/float_dsp.h"
  26 #include "libavutil/mem_internal.h"
  27 #include "libavutil/tx.h"
  28
  29 #include "avcodec.h"
  30 #include "get_bits.h"
  31 #include "put_bits.h"
  32
  33 /* size of blocks */
  34 #define BLOCK_MIN_BITS 7
  35 #define BLOCK_MAX_BITS 11
  36 #define BLOCK_MAX_SIZE (1 << BLOCK_MAX_BITS)
  37
  38 #define BLOCK_NB_SIZES (BLOCK_MAX_BITS - BLOCK_MIN_BITS + 1)
  39
  40 /* XXX: find exact max size */
  41 #define HIGH_BAND_MAX_SIZE 16
  42
  43 #define NB_LSP_COEFS 10
  44
  45 /* XXX: is it a suitable value ? */
  46 #define MAX_CODED_SUPERFRAME_SIZE 32768
  47
  48 #define MAX_CHANNELS 2
  49
  50 #define NOISE_TAB_SIZE 8192
  51
  52 #define LSP_POW_BITS 7
  53
  54 // FIXME should be in wmadec
  55 #define VLCBITS 9
  56 #define VLCMAX ((22 + VLCBITS - 1) / VLCBITS)
  57
  58 typedef float WMACoef;          ///< type for decoded coefficients, int16_t would be enough for wma 1/2
  59
  60 typedef struct CoefVLCTable {
  61     int n;                      ///< total number of codes
  62     int max_level;
  63     const uint32_t *huffcodes;  ///< VLC bit values
  64     const uint8_t *huffbits;    ///< VLC bit size
  65     const uint16_t *levels;     ///< table to build run/level tables
  66 } CoefVLCTable;
  67
  68 typedef struct WMACodecContext {
  69     AVCodecContext *avctx;
  70     GetBitContext gb;
  71     PutBitContext pb;
  72     int version;                            ///< 1 = 0x160 (WMAV1), 2 = 0x161 (WMAV2)
  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     float *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(32, float, exponents)[MAX_CHANNELS][BLOCK_MAX_SIZE];
 115     float max_exponent[MAX_CHANNELS];
 116     WMACoef coefs1[MAX_CHANNELS][BLOCK_MAX_SIZE];
 117     DECLARE_ALIGNED(32, float, coefs)[MAX_CHANNELS][BLOCK_MAX_SIZE];
 118     DECLARE_ALIGNED(32, float, output)[BLOCK_MAX_SIZE * 2];
 119     AVTXContext *mdct_ctx[BLOCK_NB_SIZES];
 120     av_tx_fn mdct_fn[BLOCK_NB_SIZES];
 121     const float *windows[BLOCK_NB_SIZES];
 122     /* output buffer for one frame and the last for IMDCT windowing */
 123     DECLARE_ALIGNED(32, float, frame_out)[MAX_CHANNELS][BLOCK_MAX_SIZE * 2];
 124     /* last frame info */
 125     uint8_t last_superframe[MAX_CODED_SUPERFRAME_SIZE + AV_INPUT_BUFFER_PADDING_SIZE]; /* padding added */
 126     int last_bitoffset;
 127     int last_superframe_len;
 128     int exponents_initialized[MAX_CHANNELS];
 129     float noise_table[NOISE_TAB_SIZE];
 130     int noise_index;
 131     float noise_mult; /* XXX: suppress that and integrate it in the noise array */
 132     /* lsp_to_curve tables */
 133     float lsp_cos_table[BLOCK_MAX_SIZE];
 134     float lsp_pow_e_table[256];
 135     float lsp_pow_m_table1[(1 << LSP_POW_BITS)];
 136     float lsp_pow_m_table2[(1 << LSP_POW_BITS)];
 137     AVFloatDSPContext *fdsp;
 138
 139     int eof_done; /* decode flag to output remaining samples after EOF */
 140
 141 #ifdef TRACE
 142     int frame_count;
 143 #endif /* TRACE */
 144 } WMACodecContext;
 145
 146 extern const uint8_t ff_wma_hgain_hufftab[37][2];
 147 extern const float ff_wma_lsp_codebook[NB_LSP_COEFS][16];
 148 extern const uint32_t ff_aac_scalefactor_code[121];
 149 extern const uint8_t  ff_aac_scalefactor_bits[121];
 150
 151 av_warn_unused_result
 152 int ff_wma_init(AVCodecContext *avctx, int flags2);
 153
 154 int ff_wma_total_gain_to_bits(int total_gain);
 155 int ff_wma_end(AVCodecContext *avctx);
 156 unsigned int ff_wma_get_large_val(GetBitContext *gb);
 157 int ff_wma_run_level_decode(AVCodecContext *avctx, GetBitContext *gb,
 158                             const VLCElem *vlc, const float *level_table,
 159                             const uint16_t *run_table, int version,
 160                             WMACoef *ptr, int offset, int num_coefs,
 161                             int block_len, int frame_len_bits,
 162                             int coef_nb_bits);
 163
 164 #endif /* AVCODEC_WMA_H */