OLD | NEW |
(Empty) | |
| 1 /* |
| 2 * Copyright 2016 Google Inc. |
| 3 * |
| 4 * Use of this source code is governed by a BSD-style license that can be |
| 5 * found in the LICENSE file. |
| 6 */ |
| 7 |
| 8 #ifndef SkEncodedInfo_DEFINED |
| 9 #define SkEncodedInfo_DEFINED |
| 10 |
| 11 #include "SkImageInfo.h" |
| 12 |
| 13 struct SkEncodedInfo { |
| 14 public: |
| 15 |
| 16 enum Alpha { |
| 17 kOpaque_Alpha, |
| 18 kUnpremul_Alpha, |
| 19 |
| 20 // Each pixel is either fully opaque or fully transparent. |
| 21 // There is no difference between requesting kPremul or kUnpremul. |
| 22 kBinary_Alpha, |
| 23 |
| 24 // Allows us to have a default constructor. Should be treated as |
| 25 // invalid. |
| 26 kUnknown_Alpha, |
| 27 }; |
| 28 |
| 29 /* |
| 30 * We strive to make the number of components per pixel obvious through |
| 31 * our naming conventions. |
| 32 * Ex: kRGB has 3 components. kRGBA has 4 components. |
| 33 * |
| 34 * This sometimes results in redundant Alpha and Color information. |
| 35 * Ex: kRGB images must also be kOpaque. |
| 36 */ |
| 37 enum Color { |
| 38 // PNG, WBMP |
| 39 kGray_Color, |
| 40 |
| 41 // PNG |
| 42 kGrayAlpha_Color, |
| 43 |
| 44 // PNG, GIF, BMP |
| 45 kPalette_Color, |
| 46 |
| 47 // PNG, RAW |
| 48 kRGB_Color, |
| 49 kRGBA_Color, |
| 50 |
| 51 // BMP |
| 52 kBGR_Color, |
| 53 kBGRX_Color, |
| 54 kBGRA_Color, |
| 55 |
| 56 // JPEG, WEBP |
| 57 kYUV_Color, |
| 58 |
| 59 // WEBP |
| 60 kYUVA_Color, |
| 61 |
| 62 // JPEG |
| 63 // Photoshop actually writes inverted CMYK data into JPEGs, where zero |
| 64 // represents 100% ink coverage. For this reason, we treat CMYK JPEGs |
| 65 // as having inverted CMYK. libjpeg-turbo warns that this may break |
| 66 // other applications, but the CMYK JPEGs we see on the web expect to |
| 67 // be treated as inverted CMYK. |
| 68 kInvertedCMYK_Color, |
| 69 kYCCK_Color, |
| 70 |
| 71 // Allows us to have a default constructor. Should be treated as |
| 72 // invalid. |
| 73 kUnknown_Color, |
| 74 }; |
| 75 |
| 76 static SkEncodedInfo Make(Color color, Alpha alpha, int bitsPerComponent) { |
| 77 SkASSERT(1 == bitsPerComponent || |
| 78 2 == bitsPerComponent || |
| 79 4 == bitsPerComponent || |
| 80 8 == bitsPerComponent || |
| 81 16 == bitsPerComponent); |
| 82 |
| 83 switch (color) { |
| 84 case kGray_Color: |
| 85 SkASSERT(kOpaque_Alpha == alpha); |
| 86 break; |
| 87 case kGrayAlpha_Color: |
| 88 SkASSERT(kOpaque_Alpha != alpha); |
| 89 break; |
| 90 case kPalette_Color: |
| 91 SkASSERT(16 != bitsPerComponent); |
| 92 break; |
| 93 case kRGB_Color: |
| 94 case kBGR_Color: |
| 95 case kBGRX_Color: |
| 96 SkASSERT(kOpaque_Alpha == alpha); |
| 97 SkASSERT(bitsPerComponent >= 8); |
| 98 break; |
| 99 case kYUV_Color: |
| 100 case kInvertedCMYK_Color: |
| 101 case kYCCK_Color: |
| 102 SkASSERT(kOpaque_Alpha == alpha); |
| 103 SkASSERT(8 == bitsPerComponent); |
| 104 break; |
| 105 case kRGBA_Color: |
| 106 SkASSERT(kOpaque_Alpha != alpha); |
| 107 SkASSERT(bitsPerComponent >= 8); |
| 108 break; |
| 109 case kBGRA_Color: |
| 110 case kYUVA_Color: |
| 111 SkASSERT(kOpaque_Alpha != alpha); |
| 112 SkASSERT(8 == bitsPerComponent); |
| 113 break; |
| 114 default: |
| 115 SkASSERT(false); |
| 116 break; |
| 117 } |
| 118 |
| 119 return SkEncodedInfo(color, alpha, bitsPerComponent); |
| 120 } |
| 121 |
| 122 /* |
| 123 * Returns an SkImageInfo with Skia color and alpha types that are the |
| 124 * closest possible match to the encoded info. |
| 125 */ |
| 126 SkImageInfo makeImageInfo(int width, int height) const { |
| 127 switch (fColor) { |
| 128 case kGray_Color: |
| 129 SkASSERT(kOpaque_Alpha == fAlpha); |
| 130 return SkImageInfo::Make(width, height, kGray_8_SkColorType, kOp
aque_SkAlphaType); |
| 131 case kGrayAlpha_Color: |
| 132 SkASSERT(kOpaque_Alpha != fAlpha); |
| 133 return SkImageInfo::Make(width, height, kN32_SkColorType, |
| 134 kUnpremul_SkAlphaType); |
| 135 case kPalette_Color: { |
| 136 SkAlphaType alphaType = (kOpaque_Alpha == fAlpha) ? kOpaque_SkAl
phaType : |
| 137 kUnpremul_SkAlphaType; |
| 138 return SkImageInfo::Make(width, height, kIndex_8_SkColorType, al
phaType); |
| 139 } |
| 140 case kRGB_Color: |
| 141 case kBGR_Color: |
| 142 case kBGRX_Color: |
| 143 case kYUV_Color: |
| 144 case kInvertedCMYK_Color: |
| 145 case kYCCK_Color: |
| 146 SkASSERT(kOpaque_Alpha == fAlpha); |
| 147 return SkImageInfo::Make(width, height, kN32_SkColorType, kOpaqu
e_SkAlphaType); |
| 148 case kRGBA_Color: |
| 149 case kBGRA_Color: |
| 150 case kYUVA_Color: |
| 151 SkASSERT(kOpaque_Alpha != fAlpha); |
| 152 return SkImageInfo::Make(width, height, kN32_SkColorType, kUnpre
mul_SkAlphaType); |
| 153 default: |
| 154 SkASSERT(false); |
| 155 return SkImageInfo::MakeUnknown(); |
| 156 } |
| 157 } |
| 158 |
| 159 SkEncodedInfo() |
| 160 : fColor(kUnknown_Color) |
| 161 , fAlpha(kUnknown_Alpha) |
| 162 , fBitsPerComponent(0) |
| 163 {} |
| 164 |
| 165 private: |
| 166 |
| 167 SkEncodedInfo(Color color, Alpha alpha, uint8_t bitsPerComponent) |
| 168 : fColor(color) |
| 169 , fAlpha(alpha) |
| 170 , fBitsPerComponent(bitsPerComponent) |
| 171 {} |
| 172 |
| 173 Color fColor; |
| 174 Alpha fAlpha; |
| 175 uint8_t fBitsPerComponent; |
| 176 }; |
| 177 |
| 178 #endif |
OLD | NEW |