xref: /third_party/ffmpeg/libavcodec/wavpack.h (revision cabdff1a) 
1/*
2 * WavPack decoder/encoder common code
3 * Copyright (c) 2006,2011 Konstantin Shishkov
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_WAVPACK_H
23#define AVCODEC_WAVPACK_H
24
25#include <limits.h>
26#include <stdint.h>
27#include "libavutil/attributes.h"
28#include "libavutil/intmath.h"
29
30#define MAX_TERMS      16
31#define MAX_TERM        8
32
33#define WV_HEADER_SIZE    32
34
35#define WV_MONO           0x00000004
36#define WV_JOINT_STEREO   0x00000010
37#define WV_CROSS_DECORR   0x00000020
38#define WV_FLOAT_DATA     0x00000080
39#define WV_INT32_DATA     0x00000100
40#define WV_FALSE_STEREO   0x40000000
41#define WV_DSD_DATA       0x80000000
42
43#define WV_HYBRID_MODE    0x00000008
44#define WV_HYBRID_SHAPE   0x00000008
45#define WV_HYBRID_BITRATE 0x00000200
46#define WV_HYBRID_BALANCE 0x00000400
47#define WV_INITIAL_BLOCK  0x00000800
48#define WV_FINAL_BLOCK    0x00001000
49
50#define WV_MONO_DATA    (WV_MONO | WV_FALSE_STEREO)
51
52#define WV_SINGLE_BLOCK (WV_INITIAL_BLOCK | WV_FINAL_BLOCK)
53
54#define WV_FLT_SHIFT_ONES 0x01
55#define WV_FLT_SHIFT_SAME 0x02
56#define WV_FLT_SHIFT_SENT 0x04
57#define WV_FLT_ZERO_SENT  0x08
58#define WV_FLT_ZERO_SIGN  0x10
59
60#define WV_MAX_SAMPLES    150000
61
62enum WP_ID_Flags {
63    WP_IDF_MASK   = 0x3F,
64    WP_IDF_IGNORE = 0x20,
65    WP_IDF_ODD    = 0x40,
66    WP_IDF_LONG   = 0x80
67};
68
69enum WP_ID {
70    WP_ID_DUMMY = 0,
71    WP_ID_ENCINFO,
72    WP_ID_DECTERMS,
73    WP_ID_DECWEIGHTS,
74    WP_ID_DECSAMPLES,
75    WP_ID_ENTROPY,
76    WP_ID_HYBRID,
77    WP_ID_SHAPING,
78    WP_ID_FLOATINFO,
79    WP_ID_INT32INFO,
80    WP_ID_DATA,
81    WP_ID_CORR,
82    WP_ID_EXTRABITS,
83    WP_ID_CHANINFO,
84    WP_ID_DSD_DATA,
85    WP_ID_SAMPLE_RATE = 0x27,
86};
87
88typedef struct Decorr {
89    int delta;
90    int value;
91    int weightA;
92    int weightB;
93    int samplesA[MAX_TERM];
94    int samplesB[MAX_TERM];
95    int sumA;
96    int sumB;
97} Decorr;
98
99typedef struct WvChannel {
100    int median[3];
101    int slow_level, error_limit;
102    unsigned bitrate_acc, bitrate_delta;
103} WvChannel;
104
105// macros for manipulating median values
106#define GET_MED(n) ((c->median[n] >> 4) + 1)
107#define DEC_MED(n) c->median[n] -= ((int)(c->median[n] + (128U >> (n)) - 2) / (128 >> (n))) * 2U
108#define INC_MED(n) c->median[n] += ((int)(c->median[n] + (128U >> (n))    ) / (128 >> (n))) * 5U
109
110// macros for applying weight
111#define UPDATE_WEIGHT_CLIP(weight, delta, samples, in) \
112    if ((samples) && (in)) { \
113        if (((samples) ^ (in)) < 0) { \
114            (weight) -= (delta); \
115            if ((weight) < -1024) \
116                (weight) = -1024; \
117        } else { \
118            (weight) += (delta); \
119            if ((weight) > 1024) \
120                (weight) = 1024; \
121        } \
122    }
123
124static const int wv_rates[16] = {
125     6000,  8000,  9600, 11025, 12000, 16000,  22050, 24000,
126    32000, 44100, 48000, 64000, 88200, 96000, 192000,     0
127};
128
129// exponent table copied from WavPack source
130extern const uint8_t ff_wp_exp2_table[256];
131extern const uint8_t ff_wp_log2_table[256];
132
133static av_always_inline int wp_exp2(int16_t val)
134{
135    int res, neg = 0;
136
137    if (val < 0) {
138        val = -val;
139        neg = 1;
140    }
141
142    res   = ff_wp_exp2_table[val & 0xFF] | 0x100;
143    val >>= 8;
144    if (val > 31U)
145        return INT_MIN;
146    res   = (val > 9) ? (res << (val - 9)) : (res >> (9 - val));
147    return neg ? -res : res;
148}
149
150static av_always_inline int wp_log2(uint32_t val)
151{
152    int bits;
153
154    if (!val)
155        return 0;
156    if (val == 1)
157        return 256;
158    val += val >> 9;
159    bits = av_log2(val) + 1;
160    if (bits < 9)
161        return (bits << 8) + ff_wp_log2_table[(val << (9 - bits)) & 0xFF];
162    else
163        return (bits << 8) + ff_wp_log2_table[(val >> (bits - 9)) & 0xFF];
164}
165
166#endif /* AVCODEC_WAVPACK_H */
167