1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
|
/*
* Copyright 2007 The Android Open Source Project
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "bmpdecoderhelper.h"
#include "SkColorPriv.h"
#include "SkImageDecoder.h"
#include "SkScaledBitmapSampler.h"
#include "SkStream.h"
#include "SkStreamPriv.h"
#include "SkTDArray.h"
class SkBMPImageDecoder : public SkImageDecoder {
public:
SkBMPImageDecoder() {}
Format getFormat() const SK_OVERRIDE {
return kBMP_Format;
}
protected:
Result onDecode(SkStream* stream, SkBitmap* bm, Mode mode) SK_OVERRIDE;
private:
typedef SkImageDecoder INHERITED;
};
///////////////////////////////////////////////////////////////////////////////
DEFINE_DECODER_CREATOR(BMPImageDecoder);
///////////////////////////////////////////////////////////////////////////////
static bool is_bmp(SkStreamRewindable* stream) {
static const char kBmpMagic[] = { 'B', 'M' };
char buffer[sizeof(kBmpMagic)];
return stream->read(buffer, sizeof(kBmpMagic)) == sizeof(kBmpMagic) &&
!memcmp(buffer, kBmpMagic, sizeof(kBmpMagic));
}
static SkImageDecoder* sk_libbmp_dfactory(SkStreamRewindable* stream) {
if (is_bmp(stream)) {
return SkNEW(SkBMPImageDecoder);
}
return NULL;
}
static SkImageDecoder_DecodeReg gReg(sk_libbmp_dfactory);
static SkImageDecoder::Format get_format_bmp(SkStreamRewindable* stream) {
if (is_bmp(stream)) {
return SkImageDecoder::kBMP_Format;
}
return SkImageDecoder::kUnknown_Format;
}
static SkImageDecoder_FormatReg gFormatReg(get_format_bmp);
///////////////////////////////////////////////////////////////////////////////
class SkBmpDecoderCallback : public image_codec::BmpDecoderCallback {
public:
// we don't copy the bitmap, just remember the pointer
SkBmpDecoderCallback(bool justBounds) : fJustBounds(justBounds) {}
// override from BmpDecoderCallback
virtual uint8* SetSize(int width, int height) {
fWidth = width;
fHeight = height;
if (fJustBounds) {
return NULL;
}
fRGB.setCount(width * height * 3); // 3 == r, g, b
return fRGB.begin();
}
int width() const { return fWidth; }
int height() const { return fHeight; }
const uint8_t* rgb() const { return fRGB.begin(); }
private:
SkTDArray<uint8_t> fRGB;
int fWidth;
int fHeight;
bool fJustBounds;
};
SkImageDecoder::Result SkBMPImageDecoder::onDecode(SkStream* stream, SkBitmap* bm, Mode mode) {
// First read the entire stream, so that all of the data can be passed to
// the BmpDecoderHelper.
// Allocated space used to hold the data.
SkAutoMalloc storage;
// Byte length of all of the data.
const size_t length = SkCopyStreamToStorage(&storage, stream);
if (0 == length) {
return kFailure;
}
const bool justBounds = SkImageDecoder::kDecodeBounds_Mode == mode;
SkBmpDecoderCallback callback(justBounds);
// Now decode the BMP into callback's rgb() array [r,g,b, r,g,b, ...]
{
image_codec::BmpDecoderHelper helper;
const int max_pixels = 16383*16383; // max width*height
if (!helper.DecodeImage((const char*)storage.get(), length,
max_pixels, &callback)) {
return kFailure;
}
}
// we don't need this anymore, so free it now (before we try to allocate
// the bitmap's pixels) rather than waiting for its destructor
storage.free();
int width = callback.width();
int height = callback.height();
SkColorType colorType = this->getPrefColorType(k32Bit_SrcDepth, false);
// only accept prefConfig if it makes sense for us
if (kARGB_4444_SkColorType != colorType && kRGB_565_SkColorType != colorType) {
colorType = kN32_SkColorType;
}
SkScaledBitmapSampler sampler(width, height, getSampleSize());
bm->setInfo(SkImageInfo::Make(sampler.scaledWidth(), sampler.scaledHeight(),
colorType, kOpaque_SkAlphaType));
if (justBounds) {
return kSuccess;
}
if (!this->allocPixelRef(bm, NULL)) {
return kFailure;
}
SkAutoLockPixels alp(*bm);
if (!sampler.begin(bm, SkScaledBitmapSampler::kRGB, *this)) {
return kFailure;
}
const int srcRowBytes = width * 3;
const int dstHeight = sampler.scaledHeight();
const uint8_t* srcRow = callback.rgb();
srcRow += sampler.srcY0() * srcRowBytes;
for (int y = 0; y < dstHeight; y++) {
sampler.next(srcRow);
srcRow += sampler.srcDY() * srcRowBytes;
}
return kSuccess;
}
|
