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wma.h
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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 "get_bits.h"
27 #include "put_bits.h"
28 #include "fft.h"
29 #include "fmtconvert.h"
30 
31 /* size of blocks */
32 #define BLOCK_MIN_BITS 7
33 #define BLOCK_MAX_BITS 11
34 #define BLOCK_MAX_SIZE (1 << BLOCK_MAX_BITS)
35 
36 #define BLOCK_NB_SIZES (BLOCK_MAX_BITS - BLOCK_MIN_BITS + 1)
37 
38 /* XXX: find exact max size */
39 #define HIGH_BAND_MAX_SIZE 16
40 
41 #define NB_LSP_COEFS 10
42 
43 /* XXX: is it a suitable value ? */
44 #define MAX_CODED_SUPERFRAME_SIZE 16384
45 
46 #define MAX_CHANNELS 2
47 
48 #define NOISE_TAB_SIZE 8192
49 
50 #define LSP_POW_BITS 7
51 
52 //FIXME should be in wmadec
53 #define VLCBITS 9
54 #define VLCMAX ((22+VLCBITS-1)/VLCBITS)
55 
56 typedef float WMACoef; ///< type for decoded coefficients, int16_t would be enough for wma 1/2
57 
58 typedef struct CoefVLCTable {
59  int n; ///< total number of codes
60  int max_level;
61  const uint32_t *huffcodes; ///< VLC bit values
62  const uint8_t *huffbits; ///< VLC bit size
63  const uint16_t *levels; ///< table to build run/level tables
64 } CoefVLCTable;
65 
66 typedef struct WMACodecContext {
67  AVCodecContext* avctx;
68  GetBitContext gb;
69  PutBitContext pb;
70  int version; ///< 1 = 0x160 (WMAV1), 2 = 0x161 (WMAV2)
71  int use_bit_reservoir;
72  int use_variable_block_len;
73  int use_exp_vlc; ///< exponent coding: 0 = lsp, 1 = vlc + delta
74  int use_noise_coding; ///< true if perceptual noise is added
75  int byte_offset_bits;
76  VLC exp_vlc;
77  int exponent_sizes[BLOCK_NB_SIZES];
78  uint16_t exponent_bands[BLOCK_NB_SIZES][25];
79  int high_band_start[BLOCK_NB_SIZES]; ///< index of first coef in high band
80  int coefs_start; ///< first coded coef
81  int coefs_end[BLOCK_NB_SIZES]; ///< max number of coded coefficients
82  int exponent_high_sizes[BLOCK_NB_SIZES];
83  int exponent_high_bands[BLOCK_NB_SIZES][HIGH_BAND_MAX_SIZE];
84  VLC hgain_vlc;
85 
86  /* coded values in high bands */
87  int high_band_coded[MAX_CHANNELS][HIGH_BAND_MAX_SIZE];
88  int high_band_values[MAX_CHANNELS][HIGH_BAND_MAX_SIZE];
89 
90  /* there are two possible tables for spectral coefficients */
91 //FIXME the following 3 tables should be shared between decoders
92  VLC coef_vlc[2];
93  uint16_t *run_table[2];
94  float *level_table[2];
95  uint16_t *int_table[2];
96  const CoefVLCTable *coef_vlcs[2];
97  /* frame info */
98  int frame_len; ///< frame length in samples
99  int frame_len_bits; ///< frame_len = 1 << frame_len_bits
100  int nb_block_sizes; ///< number of block sizes
101  /* block info */
102  int reset_block_lengths;
103  int block_len_bits; ///< log2 of current block length
104  int next_block_len_bits; ///< log2 of next block length
105  int prev_block_len_bits; ///< log2 of prev block length
106  int block_len; ///< block length in samples
107  int block_num; ///< block number in current frame
108  int block_pos; ///< current position in frame
109  uint8_t ms_stereo; ///< true if mid/side stereo mode
110  uint8_t channel_coded[MAX_CHANNELS]; ///< true if channel is coded
111  int exponents_bsize[MAX_CHANNELS]; ///< log2 ratio frame/exp. length
112  DECLARE_ALIGNED(32, float, exponents)[MAX_CHANNELS][BLOCK_MAX_SIZE];
113  float max_exponent[MAX_CHANNELS];
114  WMACoef coefs1[MAX_CHANNELS][BLOCK_MAX_SIZE];
115  DECLARE_ALIGNED(32, float, coefs)[MAX_CHANNELS][BLOCK_MAX_SIZE];
116  DECLARE_ALIGNED(32, FFTSample, output)[BLOCK_MAX_SIZE * 2];
117  FFTContext mdct_ctx[BLOCK_NB_SIZES];
118  float *windows[BLOCK_NB_SIZES];
119  /* output buffer for one frame and the last for IMDCT windowing */
120  DECLARE_ALIGNED(32, float, frame_out)[MAX_CHANNELS][BLOCK_MAX_SIZE * 2];
121  /* last frame info */
122  uint8_t last_superframe[MAX_CODED_SUPERFRAME_SIZE + FF_INPUT_BUFFER_PADDING_SIZE]; /* padding added */
123  int last_bitoffset;
124  int last_superframe_len;
125  float noise_table[NOISE_TAB_SIZE];
126  int noise_index;
127  float noise_mult; /* XXX: suppress that and integrate it in the noise array */
128  /* lsp_to_curve tables */
129  float lsp_cos_table[BLOCK_MAX_SIZE];
130  float lsp_pow_e_table[256];
131  float lsp_pow_m_table1[(1 << LSP_POW_BITS)];
132  float lsp_pow_m_table2[(1 << LSP_POW_BITS)];
133  FmtConvertContext fmt_conv;
134  AVFloatDSPContext fdsp;
135 
136 #ifdef TRACE
137  int frame_count;
138 #endif
139 } WMACodecContext;
140 
141 extern const uint16_t ff_wma_critical_freqs[25];
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_aac_scalefactor_code[121];
146 extern const uint8_t ff_aac_scalefactor_bits[121];
147 
148 int ff_wma_init(AVCodecContext * avctx, int flags2);
149 int ff_wma_total_gain_to_bits(int total_gain);
150 int ff_wma_end(AVCodecContext *avctx);
151 unsigned int ff_wma_get_large_val(GetBitContext* gb);
152 int ff_wma_run_level_decode(AVCodecContext* avctx, GetBitContext* gb,
153  VLC *vlc,
154  const float *level_table, const uint16_t *run_table,
155  int version, WMACoef *ptr, int offset,
156  int num_coefs, int block_len, int frame_len_bits,
157  int coef_nb_bits);
158 
159 #endif /* AVCODEC_WMA_H */
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