FFmpeg
put_golomb.h
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1 /*
2  * exp golomb vlc writing stuff
3  * Copyright (c) 2003 Michael Niedermayer <michaelni@gmx.at>
4  * Copyright (c) 2004 Alex Beregszaszi
5  *
6  * This file is part of FFmpeg.
7  *
8  * FFmpeg is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * FFmpeg is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 /**
24  * @file
25  * @brief
26  * exp golomb vlc writing stuff
27  * @author Michael Niedermayer <michaelni@gmx.at> and Alex Beregszaszi
28  */
29 
30 #ifndef AVCODEC_PUT_GOLOMB_H
31 #define AVCODEC_PUT_GOLOMB_H
32 
33 #include <stdint.h>
34 #include "put_bits.h"
35 
36 extern const uint8_t ff_ue_golomb_len[256];
37 
38 /**
39  * write unsigned exp golomb code. 2^16 - 2 at most
40  */
41 static inline void set_ue_golomb(PutBitContext *pb, int i)
42 {
43  av_assert2(i >= 0);
44  av_assert2(i <= 0xFFFE);
45 
46  if (i < 256)
47  put_bits(pb, ff_ue_golomb_len[i], i + 1);
48  else {
49  int e = av_log2(i + 1);
50  put_bits(pb, 2 * e + 1, i + 1);
51  }
52 }
53 
54 /**
55  * write unsigned exp golomb code. 2^32-2 at most.
56  */
57 static inline void set_ue_golomb_long(PutBitContext *pb, uint32_t i)
58 {
59  av_assert2(i <= (UINT32_MAX - 1));
60 
61  if (i < 256)
62  put_bits(pb, ff_ue_golomb_len[i], i + 1);
63  else {
64  int e = av_log2(i + 1);
65  put_bits64(pb, 2 * e + 1, i + 1);
66  }
67 }
68 
69 /**
70  * write truncated unsigned exp golomb code.
71  */
72 static inline void set_te_golomb(PutBitContext *pb, int i, int range)
73 {
74  av_assert2(range >= 1);
75  av_assert2(i <= range);
76 
77  if (range == 2)
78  put_bits(pb, 1, i ^ 1);
79  else
80  set_ue_golomb(pb, i);
81 }
82 
83 /**
84  * write signed exp golomb code. 16 bits at most.
85  */
86 static inline void set_se_golomb(PutBitContext *pb, int i)
87 {
88  i = 2 * i - 1;
89  if (i < 0)
90  i ^= -1; //FIXME check if gcc does the right thing
91  set_ue_golomb(pb, i);
92 }
93 
94 /**
95  * write unsigned golomb rice code (ffv1).
96  */
97 static inline void set_ur_golomb(PutBitContext *pb, int i, int k, int limit,
98  int esc_len)
99 {
100  int e;
101 
102  av_assert2(i >= 0);
103 
104  e = i >> k;
105  if (e < limit)
106  put_bits(pb, e + k + 1, (1 << k) + av_mod_uintp2(i, k));
107  else
108  put_bits(pb, limit + esc_len, i - limit + 1);
109 }
110 
111 /**
112  * write unsigned golomb rice code (jpegls).
113  */
114 static inline void set_ur_golomb_jpegls(PutBitContext *pb, int i, int k,
115  int limit, int esc_len)
116 {
117  int e;
118 
119  av_assert2(i >= 0);
120 
121  e = (i >> k) + 1;
122  if (e < limit) {
123  while (e > 31) {
124  put_bits(pb, 31, 0);
125  e -= 31;
126  }
127  put_bits(pb, e, 1);
128  if (k)
129  put_sbits(pb, k, i);
130  } else {
131  while (limit > 31) {
132  put_bits(pb, 31, 0);
133  limit -= 31;
134  }
135  put_bits(pb, limit, 1);
136  put_bits(pb, esc_len, i - 1);
137  }
138 }
139 
140 /**
141  * write signed golomb rice code (ffv1).
142  */
143 static inline void set_sr_golomb(PutBitContext *pb, int i, int k, int limit,
144  int esc_len)
145 {
146  int v;
147 
148  v = -2 * i - 1;
149  v ^= (v >> 31);
150 
151  set_ur_golomb(pb, v, k, limit, esc_len);
152 }
153 
154 /**
155  * write signed golomb rice code (flac).
156  */
157 static inline void set_sr_golomb_flac(PutBitContext *pb, int i, int k,
158  int limit, int esc_len)
159 {
160  int v;
161 
162  v = -2 * i - 1;
163  v ^= (v >> 31);
164 
165  set_ur_golomb_jpegls(pb, v, k, limit, esc_len);
166 }
167 
168 #endif /* AVCODEC_PUT_GOLOMB_H */
put_sbits
static void put_sbits(PutBitContext *pb, int n, int32_t value)
Definition: put_bits.h:281
av_mod_uintp2
#define av_mod_uintp2
Definition: common.h:122
put_bits
static void put_bits(Jpeg2000EncoderContext *s, int val, int n)
put n times val bit
Definition: j2kenc.c:221
put_bits64
static void put_bits64(PutBitContext *s, int n, uint64_t value)
Write up to 64 bits into a bitstream.
Definition: put_bits.h:334
set_ur_golomb_jpegls
static void set_ur_golomb_jpegls(PutBitContext *pb, int i, int k, int limit, int esc_len)
write unsigned golomb rice code (jpegls).
Definition: put_golomb.h:114
set_ue_golomb_long
static void set_ue_golomb_long(PutBitContext *pb, uint32_t i)
write unsigned exp golomb code.
Definition: put_golomb.h:57
set_sr_golomb_flac
static void set_sr_golomb_flac(PutBitContext *pb, int i, int k, int limit, int esc_len)
write signed golomb rice code (flac).
Definition: put_golomb.h:157
PutBitContext
Definition: put_bits.h:50
set_se_golomb
static void set_se_golomb(PutBitContext *pb, int i)
write signed exp golomb code.
Definition: put_golomb.h:86
av_assert2
#define av_assert2(cond)
assert() equivalent, that does lie in speed critical code.
Definition: avassert.h:64
i
#define i(width, name, range_min, range_max)
Definition: cbs_h2645.c:269
set_te_golomb
static void set_te_golomb(PutBitContext *pb, int i, int range)
write truncated unsigned exp golomb code.
Definition: put_golomb.h:72
set_ur_golomb
static void set_ur_golomb(PutBitContext *pb, int i, int k, int limit, int esc_len)
write unsigned golomb rice code (ffv1).
Definition: put_golomb.h:97
set_ue_golomb
static void set_ue_golomb(PutBitContext *pb, int i)
write unsigned exp golomb code.
Definition: put_golomb.h:41
limit
static double limit(double x)
Definition: vf_pseudocolor.c:130
ff_ue_golomb_len
const uint8_t ff_ue_golomb_len[256]
Definition: golomb.c:89
set_sr_golomb
static void set_sr_golomb(PutBitContext *pb, int i, int k, int limit, int esc_len)
write signed golomb rice code (ffv1).
Definition: put_golomb.h:143
put_bits.h
av_log2
int av_log2(unsigned v)
Definition: intmath.c:26