FFmpeg
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 
27 #include "avcodec.h"
28 #include "fft.h"
29 #include "get_bits.h"
30 #include "put_bits.h"
31 
32 /* size of blocks */
33 #define BLOCK_MIN_BITS 7
34 #define BLOCK_MAX_BITS 11
35 #define BLOCK_MAX_SIZE (1 << BLOCK_MAX_BITS)
36 
37 #define BLOCK_NB_SIZES (BLOCK_MAX_BITS - BLOCK_MIN_BITS + 1)
38 
39 /* XXX: find exact max size */
40 #define HIGH_BAND_MAX_SIZE 16
41 
42 #define NB_LSP_COEFS 10
43 
44 /* XXX: is it a suitable value ? */
45 #define MAX_CODED_SUPERFRAME_SIZE 32768
46 
47 #define MAX_CHANNELS 2
48 
49 #define NOISE_TAB_SIZE 8192
50 
51 #define LSP_POW_BITS 7
52 
53 // FIXME should be in wmadec
54 #define VLCBITS 9
55 #define VLCMAX ((22 + VLCBITS - 1) / VLCBITS)
56 
57 typedef float WMACoef;
58 
59 typedef struct CoefVLCTable {
60  int n;
61  int max_level;
62  const uint32_t *huffcodes;
63  const uint8_t *huffbits;
64  const uint16_t *levels;
65 } CoefVLCTable;
66 
67 typedef struct WMACodecContext {
68  AVCodecContext *avctx;
69  GetBitContext gb;
70  PutBitContext pb;
71  int version;
72  int use_bit_reservoir;
73  int use_variable_block_len;
76  int byte_offset_bits;
77  VLC exp_vlc;
78  int exponent_sizes[BLOCK_NB_SIZES];
79  uint16_t exponent_bands[BLOCK_NB_SIZES][25];
80  int high_band_start[BLOCK_NB_SIZES];
82  int coefs_end[BLOCK_NB_SIZES];
83  int exponent_high_sizes[BLOCK_NB_SIZES];
84  int exponent_high_bands[BLOCK_NB_SIZES][HIGH_BAND_MAX_SIZE];
85  VLC hgain_vlc;
86 
87  /* coded values in high bands */
88  int high_band_coded[MAX_CHANNELS][HIGH_BAND_MAX_SIZE];
89  int high_band_values[MAX_CHANNELS][HIGH_BAND_MAX_SIZE];
90 
91  /* there are two possible tables for spectral coefficients */
92 // FIXME the following 3 tables should be shared between decoders
93  VLC coef_vlc[2];
94  uint16_t *run_table[2];
95  float *level_table[2];
96  uint16_t *int_table[2];
97  const CoefVLCTable *coef_vlcs[2];
98  /* frame info */
99  int frame_len;
102  /* block info */
103  int reset_block_lengths;
107  int block_len;
108  int block_num;
109  int block_pos;
110  uint8_t ms_stereo;
111  uint8_t channel_coded[MAX_CHANNELS];
112  int exponents_bsize[MAX_CHANNELS];
113  DECLARE_ALIGNED(32, float, exponents)[MAX_CHANNELS][BLOCK_MAX_SIZE];
114  float max_exponent[MAX_CHANNELS];
115  WMACoef coefs1[MAX_CHANNELS][BLOCK_MAX_SIZE];
116  DECLARE_ALIGNED(32, float, coefs)[MAX_CHANNELS][BLOCK_MAX_SIZE];
117  DECLARE_ALIGNED(32, FFTSample, output)[BLOCK_MAX_SIZE * 2];
118  FFTContext mdct_ctx[BLOCK_NB_SIZES];
119  const float *windows[BLOCK_NB_SIZES];
120  /* output buffer for one frame and the last for IMDCT windowing */
121  DECLARE_ALIGNED(32, float, frame_out)[MAX_CHANNELS][BLOCK_MAX_SIZE * 2];
122  /* last frame info */
123  uint8_t last_superframe[MAX_CODED_SUPERFRAME_SIZE + AV_INPUT_BUFFER_PADDING_SIZE]; /* padding added */
124  int last_bitoffset;
125  int last_superframe_len;
126  float noise_table[NOISE_TAB_SIZE];
127  int noise_index;
128  float noise_mult; /* XXX: suppress that and integrate it in the noise array */
129  /* lsp_to_curve tables */
130  float lsp_cos_table[BLOCK_MAX_SIZE];
131  float lsp_pow_e_table[256];
132  float lsp_pow_m_table1[(1 << LSP_POW_BITS)];
133  float lsp_pow_m_table2[(1 << LSP_POW_BITS)];
134  AVFloatDSPContext *fdsp;
135 
136 #ifdef TRACE
137  int frame_count;
138 #endif /* TRACE */
140 
141 extern const uint16_t ff_wma_hgain_huffcodes[37];
142 extern const uint8_t ff_wma_hgain_huffbits[37];
143 extern const float ff_wma_lsp_codebook[NB_LSP_COEFS][16];
144 extern const uint32_t ff_aac_scalefactor_code[121];
145 extern const uint8_t ff_aac_scalefactor_bits[121];
146 
147 av_warn_unused_result
148 int ff_wma_init(AVCodecContext *avctx, int flags2);
149 
150 int ff_wma_total_gain_to_bits(int total_gain);
151 int ff_wma_end(AVCodecContext *avctx);
152 unsigned int ff_wma_get_large_val(GetBitContext *gb);
153 int ff_wma_run_level_decode(AVCodecContext *avctx, GetBitContext *gb,
154  VLC *vlc, const float *level_table,
155  const uint16_t *run_table, int version,
156  WMACoef *ptr, int offset, int num_coefs,
157  int block_len, int frame_len_bits,
158  int coef_nb_bits);
159 
160 #endif /* AVCODEC_WMA_H */
Definition: put_bits.h:35
int next_block_len_bits
log2 of next block length
Definition: wma.h:105
int block_len
block length in samples
Definition: wma.h:107
const uint8_t * huffbits
VLC bit size.
Definition: wma.h:63
int n
total number of codes
Definition: wma.h:60
Definition: wma.h:59
int block_pos
current position in frame
Definition: wma.h:109
const uint32_t * huffcodes
VLC bit values.
Definition: wma.h:62
#define DECLARE_ALIGNED(n, t, v)
Declare a variable that is aligned in memory.
Definition: mem.h:120
bitstream reader API header.
int nb_block_sizes
number of block sizes
Definition: wma.h:101
Definition: vlc.h:26
Definition: fft.h:88
int version
1 = 0x160 (WMAV1), 2 = 0x161 (WMAV2)
Definition: wma.h:71
Definition: float_dsp.h:24
int frame_len
frame length in samples
Definition: wma.h:99
int frame_len_bits
frame_len = 1 << frame_len_bits
Definition: wma.h:100
Libavcodec external API header.
int use_exp_vlc
exponent coding: 0 = lsp, 1 = vlc + delta
Definition: wma.h:74
main external API structure.
Definition: avcodec.h:1518
int block_num
block number in current frame
Definition: wma.h:108
int use_noise_coding
true if perceptual noise is added
Definition: wma.h:75
uint8_t ms_stereo
true if mid/side stereo mode
Definition: wma.h:110
int prev_block_len_bits
log2 of prev block length
Definition: wma.h:106
Definition: get_bits.h:56
#define AV_INPUT_BUFFER_PADDING_SIZE
Required number of additionally allocated bytes at the end of the input bitstream for decoding...
Definition: avcodec.h:773
int coefs_start
first coded coef
Definition: wma.h:81
Definition: wma.h:67
int block_len_bits
log2 of current block length
Definition: wma.h:104
const uint16_t * levels
table to build run/level tables
Definition: wma.h:64
bitstream writer API