1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
|
/*****************************************************************************/
// Copyright 2006-2008 Adobe Systems Incorporated
// All Rights Reserved.
//
// NOTICE: Adobe permits you to use, modify, and distribute this file in
// accordance with the terms of the Adobe license agreement accompanying it.
/*****************************************************************************/
/* $Id: //mondo/dng_sdk_1_4/dng_sdk/source/dng_1d_table.h#1 $ */
/* $DateTime: 2012/05/30 13:28:51 $ */
/* $Change: 832332 $ */
/* $Author: tknoll $ */
/** \file
* Definition of a lookup table based 1D floating-point to floating-point function abstraction using linear interpolation.
*/
/*****************************************************************************/
#ifndef __dng_1d_table__
#define __dng_1d_table__
/*****************************************************************************/
#include "dng_assertions.h"
#include "dng_auto_ptr.h"
#include "dng_classes.h"
#include "dng_types.h"
/*****************************************************************************/
/// \brief A 1D floating-point lookup table using linear interpolation.
class dng_1d_table
{
public:
/// Constants denoting size of table.
enum
{
kTableBits = 12, //< Table is always a power of 2 in size. This is log2(kTableSize).
kTableSize = (1 << kTableBits) //< Number of entries in table.
};
protected:
AutoPtr<dng_memory_block> fBuffer;
real32 *fTable;
public:
dng_1d_table ();
virtual ~dng_1d_table ();
/// Set up table, initialize entries using functiion.
/// This method can throw an exception, e.g. if there is not enough memory.
/// \param allocator Memory allocator from which table memory is allocated.
/// \param function Table is initialized with values of finction.Evalluate(0.0) to function.Evaluate(1.0).
/// \param subSample If true, only sample the function a limited number of times and interpolate.
void Initialize (dng_memory_allocator &allocator,
const dng_1d_function &function,
bool subSample = false);
/// Lookup and interpolate mapping for an input.
/// \param x value from 0.0 to 1.0 used as input for mapping
/// \retval Approximation of function.Evaluate(x)
real32 Interpolate (real32 x) const
{
real32 y = x * (real32) kTableSize;
int32 index = (int32) y;
DNG_ASSERT (index >= 0 && index <= kTableSize,
"dng_1d_table::Interpolate parameter out of range");
real32 z = (real32) index;
real32 fract = y - z;
return fTable [index ] * (1.0f - fract) +
fTable [index + 1] * ( fract);
}
/// Direct access function for table data.
const real32 * Table () const
{
return fTable;
}
/// Expand the table to a 16-bit to 16-bit table.
void Expand16 (uint16 *table16) const;
private:
void SubDivide (const dng_1d_function &function,
uint32 lower,
uint32 upper,
real32 maxDelta);
// Hidden copy constructor and assignment operator.
dng_1d_table (const dng_1d_table &table);
dng_1d_table & operator= (const dng_1d_table &table);
};
/*****************************************************************************/
#endif
/*****************************************************************************/
|
