1/*
2 * Copyright (C) 2010 Google Inc. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 *
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
15 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
16 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
17 * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
18 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
19 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
20 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
21 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26#ifndef ImageOrientation_h
27#define ImageOrientation_h
28
29namespace WebCore {
30
31class AffineTransform;
32class FloatSize;
33
34// This enum intentionally matches the orientation values from the EXIF spec.
35// See JEITA CP-3451, page 18. http://www.exif.org/Exif2-2.PDF
36enum ImageOrientationEnum {
37 // "TopLeft" means that the 0 row starts at the Top, the 0 column starts at the Left.
38 OriginTopLeft = 1, // default
39 OriginTopRight = 2, // mirror along y-axis
40 OriginBottomRight = 3, // 180 degree rotation
41 OriginBottomLeft = 4, // mirror along the x-axis
42 OriginLeftTop = 5, // mirror along x-axis + 270 degree CW rotation
43 OriginRightTop = 6, // 90 degree CW rotation
44 OriginRightBottom = 7, // mirror along x-axis + 90 degree CW rotation
45 OriginLeftBottom = 8, // 270 degree CW rotation
46 // All other values are "reserved" as of EXIF 2.2
47 DefaultImageOrientation = OriginTopLeft,
48};
49
50enum RespectImageOrientationEnum {
51 DoNotRespectImageOrientation = 0,
52 RespectImageOrientation = 1
53};
54
55struct ImageOrientationDescription {
56 ImageOrientationDescription(RespectImageOrientationEnum shouldRespectImageOrientation,
57 ImageOrientationEnum orientation)
58 : m_respectOrientation(shouldRespectImageOrientation)
59 , m_orientation(orientation)
60 {
61 }
62
63 ImageOrientationDescription()
64 : m_respectOrientation(DoNotRespectImageOrientation)
65 , m_orientation(DefaultImageOrientation)
66 {
67 }
68
69 ImageOrientationDescription(RespectImageOrientationEnum shouldRespectImageOrientation)
70 : m_respectOrientation(shouldRespectImageOrientation)
71 , m_orientation(DefaultImageOrientation)
72 {
73 }
74
75 void setRespectImageOrientation(RespectImageOrientationEnum shouldRespectImageOrientation) { m_respectOrientation = shouldRespectImageOrientation; }
76 RespectImageOrientationEnum respectImageOrientation() { return m_respectOrientation; }
77
78 void setImageOrientationEnum(ImageOrientationEnum orientation) { m_orientation = orientation; }
79 ImageOrientationEnum imageOrientation() { return m_orientation; }
80
81 RespectImageOrientationEnum m_respectOrientation;
82 ImageOrientationEnum m_orientation;
83};
84
85class ImageOrientation {
86public:
87 ImageOrientation()
88 : m_orientation(DefaultImageOrientation)
89 {
90 }
91
92 explicit ImageOrientation(ImageOrientationEnum orientation)
93 : m_orientation(orientation)
94 {
95 }
96
97 bool usesWidthAsHeight() const
98 {
99 // Values 5 through 8 all flip the width/height.
100 return m_orientation >= OriginLeftTop;
101 }
102
103 // ImageOrientationEnum currently matches EXIF values, however code outside
104 // this function should never assume that.
105 static ImageOrientation fromEXIFValue(int exifValue)
106 {
107 // Values direct from images may be invalid, in which case we use the default.
108 if (exifValue < OriginTopLeft || exifValue > OriginLeftBottom)
109 return ImageOrientation();
110 return ImageOrientation(static_cast<ImageOrientationEnum>(exifValue));
111 }
112
113 // This transform can be used for drawing an image according to the orientation.
114 // It should be used in a right-handed coordinate system.
115 AffineTransform transformFromDefault(const FloatSize& drawnSize) const;
116
117 inline operator ImageOrientationEnum() const { return m_orientation; }
118
119 inline bool operator==(const ImageOrientation& other) const { return other.m_orientation == m_orientation; }
120 inline bool operator!=(const ImageOrientation& other) const { return !(*this == other); }
121
122private:
123 // FIXME: This only needs to be one byte.
124 ImageOrientationEnum m_orientation;
125};
126
127} // namespace WebCore
128
129#endif // ImageOrientation_h
130