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 if (kUnknown_SkAlphaType == alphaType) {
65 return false;
66 }
67 break;
68 case kRGB_565_SkColorType:
69 case kGray_8_SkColorType:
70 alphaType = kOpaque_SkAlphaType;
71 break;
72 default:
73 return false;
74 }
75 if (canonical) {
76 *canonical = alphaType;
77 }
78 return true;
79 }
80
81 ///////////////////////////////////////////////////////////////////////////////////////////////////
82
83 #include "SkReadPixelsRec.h"
84
trim(int srcWidth,int srcHeight)85 bool SkReadPixelsRec::trim(int srcWidth, int srcHeight) {
86 switch (fInfo.colorType()) {
87 case kUnknown_SkColorType:
88 case kIndex_8_SkColorType:
89 return false;
90 default:
91 break;
92 }
93 if (NULL == fPixels || fRowBytes < fInfo.minRowBytes()) {
94 return false;
95 }
96 if (0 == fInfo.width() || 0 == fInfo.height()) {
97 return false;
98 }
99
100 int x = fX;
101 int y = fY;
102 SkIRect srcR = SkIRect::MakeXYWH(x, y, fInfo.width(), fInfo.height());
103 if (!srcR.intersect(0, 0, srcWidth, srcHeight)) {
104 return false;
105 }
106
107 // if x or y are negative, then we have to adjust pixels
108 if (x > 0) {
109 x = 0;
110 }
111 if (y > 0) {
112 y = 0;
113 }
114 // here x,y are either 0 or negative
115 fPixels = ((char*)fPixels - y * fRowBytes - x * fInfo.bytesPerPixel());
116 // the intersect may have shrunk info's logical size
117 fInfo = fInfo.makeWH(srcR.width(), srcR.height());
118 fX = srcR.x();
119 fY = srcR.y();
120
121 return true;
122 }
123
124