1 /*
2 * Copyright (c) 2008, 2009, 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 are
6 * met:
7 *
8 * * Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * * Redistributions in binary form must reproduce the above
11 * copyright notice, this list of conditions and the following disclaimer
12 * in the documentation and/or other materials provided with the
13 * distribution.
14 * * Neither the name of Google Inc. nor the names of its
15 * contributors may be used to endorse or promote products derived from
16 * this software without specific prior written permission.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
22 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
23 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
24 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
28 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 */
30
31 #include "config.h"
32 #include "BMPImageDecoder.h"
33
34 #include "BMPImageReader.h"
35
36 namespace WebCore {
37
38 // Number of bits in .BMP used to store the file header (doesn't match
39 // "sizeof(BMPImageDecoder::BitmapFileHeader)" since we omit some fields and
40 // don't pack).
41 static const size_t sizeOfFileHeader = 14;
42
BMPImageDecoder(ImageSource::AlphaOption alphaOption,ImageSource::GammaAndColorProfileOption gammaAndColorProfileOption)43 BMPImageDecoder::BMPImageDecoder(ImageSource::AlphaOption alphaOption,
44 ImageSource::GammaAndColorProfileOption gammaAndColorProfileOption)
45 : ImageDecoder(alphaOption, gammaAndColorProfileOption)
46 , m_decodedOffset(0)
47 {
48 }
49
setData(SharedBuffer * data,bool allDataReceived)50 void BMPImageDecoder::setData(SharedBuffer* data, bool allDataReceived)
51 {
52 if (failed())
53 return;
54
55 ImageDecoder::setData(data, allDataReceived);
56 if (m_reader)
57 m_reader->setData(data);
58 }
59
isSizeAvailable()60 bool BMPImageDecoder::isSizeAvailable()
61 {
62 if (!ImageDecoder::isSizeAvailable())
63 decode(true);
64
65 return ImageDecoder::isSizeAvailable();
66 }
67
frameBufferAtIndex(size_t index)68 ImageFrame* BMPImageDecoder::frameBufferAtIndex(size_t index)
69 {
70 if (index)
71 return 0;
72
73 if (m_frameBufferCache.isEmpty()) {
74 m_frameBufferCache.resize(1);
75 m_frameBufferCache.first().setPremultiplyAlpha(m_premultiplyAlpha);
76 }
77
78 ImageFrame* buffer = &m_frameBufferCache.first();
79 if (buffer->status() != ImageFrame::FrameComplete)
80 decode(false);
81 return buffer;
82 }
83
setFailed()84 bool BMPImageDecoder::setFailed()
85 {
86 m_reader.clear();
87 return ImageDecoder::setFailed();
88 }
89
decode(bool onlySize)90 void BMPImageDecoder::decode(bool onlySize)
91 {
92 if (failed())
93 return;
94
95 // If we couldn't decode the image but we've received all the data, decoding
96 // has failed.
97 if (!decodeHelper(onlySize) && isAllDataReceived())
98 setFailed();
99 // If we're done decoding the image, we don't need the BMPImageReader
100 // anymore. (If we failed, |m_reader| has already been cleared.)
101 else if (!m_frameBufferCache.isEmpty() && (m_frameBufferCache.first().status() == ImageFrame::FrameComplete))
102 m_reader.clear();
103 }
104
decodeHelper(bool onlySize)105 bool BMPImageDecoder::decodeHelper(bool onlySize)
106 {
107 size_t imgDataOffset = 0;
108 if ((m_decodedOffset < sizeOfFileHeader) && !processFileHeader(&imgDataOffset))
109 return false;
110
111 if (!m_reader) {
112 m_reader.set(new BMPImageReader(this, m_decodedOffset, imgDataOffset, false));
113 m_reader->setData(m_data.get());
114 }
115
116 if (!m_frameBufferCache.isEmpty())
117 m_reader->setBuffer(&m_frameBufferCache.first());
118
119 return m_reader->decodeBMP(onlySize);
120 }
121
processFileHeader(size_t * imgDataOffset)122 bool BMPImageDecoder::processFileHeader(size_t* imgDataOffset)
123 {
124 ASSERT(imgDataOffset);
125
126 // Read file header.
127 ASSERT(!m_decodedOffset);
128 if (m_data->size() < sizeOfFileHeader)
129 return false;
130 const uint16_t fileType = (m_data->data()[0] << 8) | static_cast<uint8_t>(m_data->data()[1]);
131 *imgDataOffset = readUint32(10);
132 m_decodedOffset = sizeOfFileHeader;
133
134 // See if this is a bitmap filetype we understand.
135 enum {
136 BMAP = 0x424D, // "BM"
137 // The following additional OS/2 2.x header values (see
138 // http://www.fileformat.info/format/os2bmp/egff.htm ) aren't widely
139 // decoded, and are unlikely to be in much use.
140 /*
141 ICON = 0x4943, // "IC"
142 POINTER = 0x5054, // "PT"
143 COLORICON = 0x4349, // "CI"
144 COLORPOINTER = 0x4350, // "CP"
145 BITMAPARRAY = 0x4241, // "BA"
146 */
147 };
148 return (fileType == BMAP) || setFailed();
149 }
150
151 } // namespace WebCore
152