1 /*
2  * Copyright (C) 2007,2008   Alex Shulgin
3  *
4  * This file is part of png++ the C++ wrapper for libpng.  PNG++ is free
5  * software; the exact copying conditions are as follows:
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions are met:
9  *
10  * 1. Redistributions of source code must retain the above copyright notice,
11  * this list of conditions and the following disclaimer.
12  *
13  * 2. Redistributions in binary form must reproduce the above copyright
14  * notice, this list of conditions and the following disclaimer in the
15  * documentation and/or other materials provided with the distribution.
16  *
17  * 3. The name of the author may not be used to endorse or promote products
18  * derived from this software without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
21  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
22  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN
23  * NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
24  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
25  * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
26  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
27  * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
28  * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
29  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30  */
31 #ifndef PNGPP_GRAY_PIXEL_HPP_INCLUDED
32 #define PNGPP_GRAY_PIXEL_HPP_INCLUDED
33 
34 #include "types.hpp"
35 #include "packed_pixel.hpp"
36 #include "pixel_traits.hpp"
37 
38 namespace png
39 {
40 
41     /**
42      * \brief The 8-bit Grayscale pixel type.
43      */
44     typedef byte gray_pixel;
45 
46     /**
47      * \brief The 16-bit Grayscale pixel type.
48      */
49     typedef uint_16 gray_pixel_16;
50 
51     /**
52      * \brief The packed gray pixel class template.  The available
53      * specializations are for 1-, 2- and 4-bit pixels.
54      */
55     template< int bits >
56     class packed_gray_pixel
57         : public packed_pixel< bits >
58     {
59     public:
packed_gray_pixel(byte value=0)60         packed_gray_pixel(byte value = 0)
61             : packed_pixel< bits >(value)
62         {
63         }
64     };
65 
66     /**
67      * \brief The 1-bit Grayscale pixel type.
68      */
69     typedef packed_gray_pixel< 1 > gray_pixel_1;
70 
71     /**
72      * \brief The 2-bit Grayscale pixel type.
73      */
74     typedef packed_gray_pixel< 2 > gray_pixel_2;
75 
76     /**
77      * \brief The 4-bit Grayscale pixel type.
78      */
79     typedef packed_gray_pixel< 4 > gray_pixel_4;
80 
81     /**
82      * \brief Pixel traits specialization for gray_pixel.
83      */
84     template<>
85     struct pixel_traits< gray_pixel >
86         : basic_pixel_traits< gray_pixel, byte, color_type_gray >
87     {
88     };
89 
90     /**
91      * \brief Pixel traits specialization for gray_pixel_16.
92      */
93     template<>
94     struct pixel_traits< gray_pixel_16 >
95         : basic_pixel_traits< gray_pixel_16, uint_16, color_type_gray >
96     {
97     };
98 
99     /**
100      * \brief Pixel traits specialization for packed_gray_pixel.
101      */
102     template< int bits >
103     struct pixel_traits< packed_gray_pixel< bits > >
104         : basic_pixel_traits< packed_gray_pixel< bits >, byte,
105                               color_type_gray, /* channels = */ 1, bits >
106     {
107     };
108 
109 } // namespace png
110 
111 #endif // PNGPP_GRAY_PIXEL_HPP_INCLUDED
112