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 "bitstream.h"
  26 #include "dsputil.h"
  27
  28 /* size of blocks */
  29 #define BLOCK_MIN_BITS 7
  30 #define BLOCK_MAX_BITS 11
  31 #define BLOCK_MAX_SIZE (1 << BLOCK_MAX_BITS)
  32
  33 #define BLOCK_NB_SIZES (BLOCK_MAX_BITS - BLOCK_MIN_BITS + 1)
  34
  35 /* XXX: find exact max size */
  36 #define HIGH_BAND_MAX_SIZE 16
  37
  38 #define NB_LSP_COEFS 10
  39
  40 /* XXX: is it a suitable value ? */
  41 #define MAX_CODED_SUPERFRAME_SIZE 16384
  42
  43 #define MAX_CHANNELS 2
  44
  45 #define NOISE_TAB_SIZE 8192
  46
  47 #define LSP_POW_BITS 7
  48
  49 //FIXME should be in wmadec
  50 #define VLCBITS 9
  51 #define VLCMAX ((22+VLCBITS-1)/VLCBITS)
  52
  53 typedef struct CoefVLCTable {
  54     int n;                      ///< total number of codes
  55     int max_level;
  56     const uint32_t *huffcodes;  ///< VLC bit values
  57     const uint8_t *huffbits;    ///< VLC bit size
  58     const uint16_t *levels;     ///< table to build run/level tables
  59 } CoefVLCTable;
  60
  61 typedef struct WMACodecContext {
  62     AVCodecContext* avctx;
  63     GetBitContext gb;
  64     PutBitContext pb;
  65     int sample_rate;
  66     int nb_channels;
  67     int bit_rate;
  68     int version;                            ///< 1 = 0x160 (WMAV1), 2 = 0x161 (WMAV2)
  69     int block_align;
  70     int use_bit_reservoir;
  71     int use_variable_block_len;
  72     int use_exp_vlc;                        ///< exponent coding: 0 = lsp, 1 = vlc + delta
  73     int use_noise_coding;                   ///< true if perceptual noise is added
  74     int byte_offset_bits;
  75     VLC exp_vlc;
  76     int exponent_sizes[BLOCK_NB_SIZES];
  77     uint16_t exponent_bands[BLOCK_NB_SIZES][25];
  78     int high_band_start[BLOCK_NB_SIZES];    ///< index of first coef in high band
  79     int coefs_start;                        ///< first coded coef
  80     int coefs_end[BLOCK_NB_SIZES];          ///< max number of coded coefficients
  81     int exponent_high_sizes[BLOCK_NB_SIZES];
  82     int exponent_high_bands[BLOCK_NB_SIZES][HIGH_BAND_MAX_SIZE];
  83     VLC hgain_vlc;
  84
  85     /* coded values in high bands */
  86     int high_band_coded[MAX_CHANNELS][HIGH_BAND_MAX_SIZE];
  87     int high_band_values[MAX_CHANNELS][HIGH_BAND_MAX_SIZE];
  88
  89     /* there are two possible tables for spectral coefficients */
  90 //FIXME the following 3 tables should be shared between decoders
  91     VLC coef_vlc[2];
  92     uint16_t *run_table[2];
  93     uint16_t *level_table[2];
  94     uint16_t *int_table[2];
  95     const CoefVLCTable *coef_vlcs[2];
  96     /* frame info */
  97     int frame_len;                          ///< frame length in samples
  98     int frame_len_bits;                     ///< frame_len = 1 << frame_len_bits
  99     int nb_block_sizes;                     ///< number of block sizes
 100     /* block info */
 101     int reset_block_lengths;
 102     int block_len_bits;                     ///< log2 of current block length
 103     int next_block_len_bits;                ///< log2 of next block length
 104     int prev_block_len_bits;                ///< log2 of prev block length
 105     int block_len;                          ///< block length in samples
 106     int block_num;                          ///< block number in current frame
 107     int block_pos;                          ///< current position in frame
 108     uint8_t ms_stereo;                      ///< true if mid/side stereo mode
 109     uint8_t channel_coded[MAX_CHANNELS];    ///< true if channel is coded
 110     int exponents_bsize[MAX_CHANNELS];      ///< log2 ratio frame/exp. length
 111     DECLARE_ALIGNED_16(float, exponents[MAX_CHANNELS][BLOCK_MAX_SIZE]);
 112     float max_exponent[MAX_CHANNELS];
 113     int16_t coefs1[MAX_CHANNELS][BLOCK_MAX_SIZE];
 114     DECLARE_ALIGNED_16(float, coefs[MAX_CHANNELS][BLOCK_MAX_SIZE]);
 115     DECLARE_ALIGNED_16(FFTSample, output[BLOCK_MAX_SIZE * 2]);
 116     MDCTContext mdct_ctx[BLOCK_NB_SIZES];
 117     float *windows[BLOCK_NB_SIZES];
 118     /* output buffer for one frame and the last for IMDCT windowing */
 119     DECLARE_ALIGNED_16(float, frame_out[MAX_CHANNELS][BLOCK_MAX_SIZE * 2]);
 120     /* last frame info */
 121     uint8_t last_superframe[MAX_CODED_SUPERFRAME_SIZE + 4]; /* padding added */
 122     int last_bitoffset;
 123     int last_superframe_len;
 124     float noise_table[NOISE_TAB_SIZE];
 125     int noise_index;
 126     float noise_mult; /* XXX: suppress that and integrate it in the noise array */
 127     /* lsp_to_curve tables */
 128     float lsp_cos_table[BLOCK_MAX_SIZE];
 129     float lsp_pow_e_table[256];
 130     float lsp_pow_m_table1[(1 << LSP_POW_BITS)];
 131     float lsp_pow_m_table2[(1 << LSP_POW_BITS)];
 132     DSPContext dsp;
 133
 134 #ifdef TRACE
 135     int frame_count;
 136 #endif
 137 } WMACodecContext;
 138
 139 extern const uint16_t ff_wma_hgain_huffcodes[37];
 140 extern const uint8_t ff_wma_hgain_huffbits[37];
 141 extern const float ff_wma_lsp_codebook[NB_LSP_COEFS][16];
 142 extern const uint32_t ff_wma_scale_huffcodes[121];
 143 extern const uint8_t ff_wma_scale_huffbits[121];
 144
 145 int ff_wma_init(AVCodecContext * avctx, int flags2);
 146 int ff_wma_total_gain_to_bits(int total_gain);
 147 int ff_wma_end(AVCodecContext *avctx);
 148
 149 #endif /* AVCODEC_WMA_H */