opj_intmath.h revision ee451cb395940862dad63c85adfe8f2fd55e864c 
1/*
2 * The copyright in this software is being made available under the 2-clauses
3 * BSD License, included below. This software may be subject to other third
4 * party and contributor rights, including patent rights, and no such rights
5 * are granted under this license.
6 *
7 * Copyright (c) 2002-2014, Universite catholique de Louvain (UCL), Belgium
8 * Copyright (c) 2002-2014, Professor Benoit Macq
9 * Copyright (c) 2001-2003, David Janssens
10 * Copyright (c) 2002-2003, Yannick Verschueren
11 * Copyright (c) 2003-2007, Francois-Olivier Devaux
12 * Copyright (c) 2003-2014, Antonin Descampe
13 * Copyright (c) 2005, Herve Drolon, FreeImage Team
14 * All rights reserved.
15 *
16 * Redistribution and use in source and binary forms, with or without
17 * modification, are permitted provided that the following conditions
18 * are met:
19 * 1. Redistributions of source code must retain the above copyright
20 *    notice, this list of conditions and the following disclaimer.
21 * 2. Redistributions in binary form must reproduce the above copyright
22 *    notice, this list of conditions and the following disclaimer in the
23 *    documentation and/or other materials provided with the distribution.
24 *
25 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS `AS IS'
26 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28 * ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
29 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
30 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
31 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
32 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
33 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
34 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
35 * POSSIBILITY OF SUCH DAMAGE.
36 */
37#ifndef __INT_H
38#define __INT_H
39/**
40@file opj_intmath.h
41@brief Implementation of operations on integers (INT)
42
43The functions in OPJ_INTMATH.H have for goal to realize operations on integers.
44*/
45
46/** @defgroup OPJ_INTMATH OPJ_INTMATH - Implementation of operations on integers */
47/*@{*/
48
49/** @name Exported functions (see also openjpeg.h) */
50/*@{*/
51/* ----------------------------------------------------------------------- */
52/**
53Get the minimum of two integers
54@return Returns a if a < b else b
55*/
56static INLINE OPJ_INT32 opj_int_min(OPJ_INT32 a, OPJ_INT32 b) {
57	return a < b ? a : b;
58}
59
60/**
61Get the minimum of two integers
62@return Returns a if a < b else b
63*/
64static INLINE OPJ_UINT32 opj_uint_min(OPJ_UINT32 a, OPJ_UINT32 b) {
65	return a < b ? a : b;
66}
67
68/**
69Get the maximum of two integers
70@return Returns a if a > b else b
71*/
72static INLINE OPJ_INT32 opj_int_max(OPJ_INT32 a, OPJ_INT32 b) {
73	return (a > b) ? a : b;
74}
75
76/**
77Get the maximum of two integers
78@return Returns a if a > b else b
79*/
80static INLINE OPJ_UINT32 opj_uint_max(OPJ_UINT32  a, OPJ_UINT32  b) {
81	return (a > b) ? a : b;
82}
83
84/**
85Clamp an integer inside an interval
86@return
87<ul>
88<li>Returns a if (min < a < max)
89<li>Returns max if (a > max)
90<li>Returns min if (a < min)
91</ul>
92*/
93static INLINE OPJ_INT32 opj_int_clamp(OPJ_INT32 a, OPJ_INT32 min, OPJ_INT32 max) {
94	if (a < min)
95		return min;
96	if (a > max)
97		return max;
98	return a;
99}
100/**
101@return Get absolute value of integer
102*/
103static INLINE OPJ_INT32 opj_int_abs(OPJ_INT32 a) {
104	return a < 0 ? -a : a;
105}
106/**
107Divide an integer and round upwards
108@return Returns a divided by b
109*/
110static INLINE OPJ_INT32 opj_int_ceildiv(OPJ_INT32 a, OPJ_INT32 b) {
111  assert(b);
112	return (a + b - 1) / b;
113}
114
115/**
116Divide an integer and round upwards
117@return Returns a divided by b
118*/
119static INLINE OPJ_UINT32  opj_uint_ceildiv(OPJ_UINT32  a, OPJ_UINT32  b) {
120	return (a + b - 1) / b;
121}
122
123/**
124Divide an integer by a power of 2 and round upwards
125@return Returns a divided by 2^b
126*/
127static INLINE OPJ_INT32 opj_int_ceildivpow2(OPJ_INT32 a, OPJ_INT32 b) {
128	return (OPJ_INT32)((a + (OPJ_INT64)(1 << b) - 1) >> b);
129}
130/**
131Divide an integer by a power of 2 and round downwards
132@return Returns a divided by 2^b
133*/
134static INLINE OPJ_INT32 opj_int_floordivpow2(OPJ_INT32 a, OPJ_INT32 b) {
135	return a >> b;
136}
137/**
138Get logarithm of an integer and round downwards
139@return Returns log2(a)
140*/
141static INLINE OPJ_INT32 opj_int_floorlog2(OPJ_INT32 a) {
142	OPJ_INT32 l;
143	for (l = 0; a > 1; l++) {
144		a >>= 1;
145	}
146	return l;
147}
148/**
149Get logarithm of an integer and round downwards
150@return Returns log2(a)
151*/
152static INLINE OPJ_UINT32  opj_uint_floorlog2(OPJ_UINT32  a) {
153	OPJ_UINT32  l;
154	for (l = 0; a > 1; ++l)
155	{
156		a >>= 1;
157	}
158	return l;
159}
160
161/**
162Multiply two fixed-precision rational numbers.
163@param a
164@param b
165@return Returns a * b
166*/
167static INLINE OPJ_INT32 opj_int_fix_mul(OPJ_INT32 a, OPJ_INT32 b) {
168    OPJ_INT64 temp = (OPJ_INT64) a * (OPJ_INT64) b ;
169    temp += temp & 4096;
170    return (OPJ_INT32) (temp >> 13) ;
171}
172
173/* ----------------------------------------------------------------------- */
174/*@}*/
175
176/*@}*/
177
178#endif
179