1 /*
2 * Copyright 2010 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 #include "SkImageInfo.h"
9 #include "SkReadBuffer.h"
10 #include "SkWriteBuffer.h"
11
profile_type_is_valid(SkColorProfileType profileType)12 static bool profile_type_is_valid(SkColorProfileType profileType) {
13 return (profileType >= 0) && (profileType <= kLastEnum_SkColorProfileType);
14 }
15
alpha_type_is_valid(SkAlphaType alphaType)16 static bool alpha_type_is_valid(SkAlphaType alphaType) {
17 return (alphaType >= 0) && (alphaType <= kLastEnum_SkAlphaType);
18 }
19
color_type_is_valid(SkColorType colorType)20 static bool color_type_is_valid(SkColorType colorType) {
21 return (colorType >= 0) && (colorType <= kLastEnum_SkColorType);
22 }
23
unflatten(SkReadBuffer & buffer)24 void SkImageInfo::unflatten(SkReadBuffer& buffer) {
25 fWidth = buffer.read32();
26 fHeight = buffer.read32();
27
28 uint32_t packed = buffer.read32();
29 SkASSERT(0 == (packed >> 24));
30 fProfileType = (SkColorProfileType)((packed >> 16) & 0xFF);
31 fAlphaType = (SkAlphaType)((packed >> 8) & 0xFF);
32 fColorType = (SkColorType)((packed >> 0) & 0xFF);
33 buffer.validate(profile_type_is_valid(fProfileType) &&
34 alpha_type_is_valid(fAlphaType) &&
35 color_type_is_valid(fColorType));
36 }
37
flatten(SkWriteBuffer & buffer) const38 void SkImageInfo::flatten(SkWriteBuffer& buffer) const {
39 buffer.write32(fWidth);
40 buffer.write32(fHeight);
41
42 SkASSERT(0 == (fProfileType & ~0xFF));
43 SkASSERT(0 == (fAlphaType & ~0xFF));
44 SkASSERT(0 == (fColorType & ~0xFF));
45 uint32_t packed = (fProfileType << 16) | (fAlphaType << 8) | fColorType;
46 buffer.write32(packed);
47 }
48
SkColorTypeValidateAlphaType(SkColorType colorType,SkAlphaType alphaType,SkAlphaType * canonical)49 bool SkColorTypeValidateAlphaType(SkColorType colorType, SkAlphaType alphaType,
50 SkAlphaType* canonical) {
51 switch (colorType) {
52 case kUnknown_SkColorType:
53 alphaType = kUnknown_SkAlphaType;
54 break;
55 case kAlpha_8_SkColorType:
56 if (kUnpremul_SkAlphaType == alphaType) {
57 alphaType = kPremul_SkAlphaType;
58 }
59 // fall-through
60 case kIndex_8_SkColorType:
61 case kARGB_4444_SkColorType:
62 case kRGBA_8888_SkColorType:
63 case kBGRA_8888_SkColorType:
64 case kRGBA_F16_SkColorType:
65 if (kUnknown_SkAlphaType == alphaType) {
66 return false;
67 }
68 break;
69 case kRGB_565_SkColorType:
70 case kGray_8_SkColorType:
71 alphaType = kOpaque_SkAlphaType;
72 break;
73 default:
74 return false;
75 }
76 if (canonical) {
77 *canonical = alphaType;
78 }
79 return true;
80 }
81
82 ///////////////////////////////////////////////////////////////////////////////////////////////////
83
84 #include "SkReadPixelsRec.h"
85
trim(int srcWidth,int srcHeight)86 bool SkReadPixelsRec::trim(int srcWidth, int srcHeight) {
87 switch (fInfo.colorType()) {
88 case kUnknown_SkColorType:
89 case kIndex_8_SkColorType:
90 return false;
91 default:
92 break;
93 }
94 if (nullptr == fPixels || fRowBytes < fInfo.minRowBytes()) {
95 return false;
96 }
97 if (0 == fInfo.width() || 0 == fInfo.height()) {
98 return false;
99 }
100
101 int x = fX;
102 int y = fY;
103 SkIRect srcR = SkIRect::MakeXYWH(x, y, fInfo.width(), fInfo.height());
104 if (!srcR.intersect(0, 0, srcWidth, srcHeight)) {
105 return false;
106 }
107
108 // if x or y are negative, then we have to adjust pixels
109 if (x > 0) {
110 x = 0;
111 }
112 if (y > 0) {
113 y = 0;
114 }
115 // here x,y are either 0 or negative
116 fPixels = ((char*)fPixels - y * fRowBytes - x * fInfo.bytesPerPixel());
117 // the intersect may have shrunk info's logical size
118 fInfo = fInfo.makeWH(srcR.width(), srcR.height());
119 fX = srcR.x();
120 fY = srcR.y();
121
122 return true;
123 }
124
125