1///////////////////////////////////////////////////////////////////////////
2//
3// Copyright (c) 2002, Industrial Light & Magic, a division of Lucas
4// Digital Ltd. LLC
5//
6// All rights reserved.
7//
8// Redistribution and use in source and binary forms, with or without
9// modification, are permitted provided that the following conditions are
10// met:
11// *       Redistributions of source code must retain the above copyright
12// notice, this list of conditions and the following disclaimer.
13// *       Redistributions in binary form must reproduce the above
14// copyright notice, this list of conditions and the following disclaimer
15// in the documentation and/or other materials provided with the
16// distribution.
17// *       Neither the name of Industrial Light & Magic nor the names of
18// its contributors may be used to endorse or promote products derived
19// from this software without specific prior written permission.
20//
21// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
24// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
25// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
26// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
27// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
28// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
29// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
31// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32//
33///////////////////////////////////////////////////////////////////////////
34
35
36
37//-----------------------------------------------------------------------------
38//
39//	Lookup tables for efficient application
40//	of half --> half functions to pixel data,
41//	and some commonly applied functions.
42//
43//-----------------------------------------------------------------------------
44
45#include <ImfLut.h>
46#include <math.h>
47#include <assert.h>
48
49namespace Imf {
50
51
52void
53HalfLut::apply (half *data, int nData, int stride) const
54{
55    while (nData)
56    {
57    *data = _lut (*data);
58    data += stride;
59    nData -= 1;
60    }
61}
62
63
64void
65HalfLut::apply (const Slice &data, const Imath::Box2i &dataWindow) const
66{
67    assert (data.type == HALF);
68    assert (dataWindow.min.x % data.xSampling == 0);
69    assert (dataWindow.min.y % data.ySampling == 0);
70    assert ((dataWindow.max.x - dataWindow.min.x + 1) % data.xSampling == 0);
71    assert ((dataWindow.max.y - dataWindow.min.y + 1) % data.ySampling == 0);
72
73    char *base = data.base + data.yStride *
74         (dataWindow.min.y / data.ySampling);
75
76    for (int y = dataWindow.min.y;
77     y <= dataWindow.max.y;
78     y += data.ySampling)
79    {
80    char *pixel = base + data.xStride *
81              (dataWindow.min.x / data.xSampling);
82
83    for (int x = dataWindow.min.x;
84         x <= dataWindow.max.x;
85         x += data.xSampling)
86    {
87        *(half *)pixel = _lut (*(half *)pixel);
88        pixel += data.xStride;
89    }
90
91    base += data.yStride;
92    }
93}
94
95
96void
97RgbaLut::apply (Rgba *data, int nData, int stride) const
98{
99    while (nData)
100    {
101    if (_chn & WRITE_R)
102        data->r = _lut (data->r);
103
104    if (_chn & WRITE_G)
105        data->g = _lut (data->g);
106
107    if (_chn & WRITE_B)
108        data->b = _lut (data->b);
109
110    if (_chn & WRITE_A)
111        data->a = _lut (data->a);
112
113    data += stride;
114    nData -= 1;
115    }
116}
117
118
119void
120RgbaLut::apply (Rgba *base,
121        int xStride, int yStride,
122        const Imath::Box2i &dataWindow) const
123{
124    base += dataWindow.min.y * yStride;
125
126    for (int y = dataWindow.min.y; y <= dataWindow.max.y; ++y)
127    {
128    Rgba *pixel = base + dataWindow.min.x * xStride;
129
130    for (int x = dataWindow.min.x; x <= dataWindow.max.x; ++x)
131    {
132        if (_chn & WRITE_R)
133        pixel->r = _lut (pixel->r);
134
135        if (_chn & WRITE_G)
136        pixel->g = _lut (pixel->g);
137
138        if (_chn & WRITE_B)
139        pixel->b = _lut (pixel->b);
140
141        if (_chn & WRITE_A)
142        pixel->a = _lut (pixel->a);
143
144        pixel += xStride;
145    }
146
147    base += yStride;
148    }
149}
150
151
152half
153round12log (half x)
154{
155    const float middleval = pow (2.0, -2.5);
156    int int12log;
157
158    if (x <= 0)
159    {
160    return 0;
161    }
162    else
163    {
164    int12log = int (2000.5 + 200.0 * log (x / middleval) / log (2.0));
165
166    if (int12log > 4095)
167        int12log = 4095;
168
169    if (int12log < 1)
170        int12log = 1;
171    }
172
173    return middleval * pow (2.0, (int12log - 2000.0) / 200.0);
174}
175
176} // namespace Imf
177