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1 /*
2  * Copyright (C) 2010 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
6  * are met:
7  *
8  * 1.  Redistributions of source code must retain the above copyright
9  *     notice, this list of conditions and the following disclaimer.
10  * 2.  Redistributions in binary form must reproduce the above copyright
11  *     notice, this list of conditions and the following disclaimer in the
12  *     documentation and/or other materials provided with the distribution.
13  * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
14  *     its contributors may be used to endorse or promote products derived
15  *     from this software without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
18  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
19  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
20  * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
21  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
22  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
23  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
24  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 #include "config.h"
30 #include "WEBPImageDecoder.h"
31 
32 #if USE(WEBP)
33 
34 #include "webp/decode.h"
35 
36 namespace WebCore {
37 
WEBPImageDecoder(ImageSource::AlphaOption alphaOption,ImageSource::GammaAndColorProfileOption gammaAndColorProfileOption)38 WEBPImageDecoder::WEBPImageDecoder(ImageSource::AlphaOption alphaOption,
39                                    ImageSource::GammaAndColorProfileOption gammaAndColorProfileOption)
40     : ImageDecoder(alphaOption, gammaAndColorProfileOption)
41     , m_decoder(0)
42     , m_lastVisibleRow(0)
43 {
44 }
45 
~WEBPImageDecoder()46 WEBPImageDecoder::~WEBPImageDecoder()
47 {
48 }
49 
isSizeAvailable()50 bool WEBPImageDecoder::isSizeAvailable()
51 {
52     if (!ImageDecoder::isSizeAvailable())
53          decode(true);
54 
55     return ImageDecoder::isSizeAvailable();
56 }
57 
frameBufferAtIndex(size_t index)58 ImageFrame* WEBPImageDecoder::frameBufferAtIndex(size_t index)
59 {
60     if (index)
61         return 0;
62 
63     if (m_frameBufferCache.isEmpty()) {
64         m_frameBufferCache.resize(1);
65         m_frameBufferCache[0].setPremultiplyAlpha(m_premultiplyAlpha);
66     }
67 
68     ImageFrame& frame = m_frameBufferCache[0];
69     if (frame.status() != ImageFrame::FrameComplete)
70         decode(false);
71     return &frame;
72 }
73 
74 
decode(bool onlySize)75 bool WEBPImageDecoder::decode(bool onlySize)
76 {
77     // Minimum number of bytes needed to ensure one can parse size information.
78     static const size_t sizeOfHeader = 30;
79     // Number of bytes per pixel.
80     static const int bytesPerPixel = 3;
81 
82     if (failed())
83         return false;
84 
85     const size_t dataSize = m_data->size();
86     if (dataSize < sizeOfHeader)
87         return true;
88 
89     int width, height;
90     const uint8_t* dataBytes = reinterpret_cast<const uint8_t*>(m_data->data());
91     if (!WebPGetInfo(dataBytes, dataSize, &width, &height))
92         return setFailed();
93     if (!ImageDecoder::isSizeAvailable() && !setSize(width, height))
94         return setFailed();
95     if (onlySize)
96         return true;
97 
98     bool allDataReceived = isAllDataReceived();
99     int stride = width * bytesPerPixel;
100     ASSERT(!m_frameBufferCache.isEmpty());
101     ImageFrame& buffer = m_frameBufferCache[0];
102     if (buffer.status() == ImageFrame::FrameEmpty) {
103         ASSERT(width == size().width());
104         ASSERT(height == size().height());
105         if (!buffer.setSize(width, height))
106             return setFailed();
107         buffer.setStatus(allDataReceived ? ImageFrame::FrameComplete : ImageFrame::FramePartial);
108         // FIXME: We currently hard code false below because libwebp doesn't support alpha yet.
109         buffer.setHasAlpha(false);
110         buffer.setOriginalFrameRect(IntRect(IntPoint(), size()));
111         m_rgbOutput.resize(height * stride);
112     }
113     int newLastVisibleRow = 0; // Last completed row.
114     if (allDataReceived) {
115         if (!WebPDecodeRGBInto(dataBytes, dataSize, m_rgbOutput.data(), m_rgbOutput.size(), stride))
116             return setFailed();
117         newLastVisibleRow = height;
118     } else {
119         if (!m_decoder) {
120             m_decoder = WebPINewRGB(MODE_RGB, m_rgbOutput.data(), m_rgbOutput.size(), stride);
121             if (!m_decoder)
122                 return setFailed();
123         }
124         const VP8StatusCode status = WebPIUpdate(m_decoder, dataBytes, dataSize);
125         if (status != VP8_STATUS_OK && status != VP8_STATUS_SUSPENDED)
126             return setFailed();
127         if (!WebPIDecGetRGB(m_decoder, &newLastVisibleRow, 0, 0, 0))
128             return setFailed();
129         ASSERT(newLastVisibleRow >= 0);
130         ASSERT(newLastVisibleRow <= height);
131     }
132     // FIXME: remove this data copy.
133     for (int y = m_lastVisibleRow; y < newLastVisibleRow; ++y) {
134         const uint8_t* const src = &m_rgbOutput[y * stride];
135         for (int x = 0; x < width; ++x)
136             buffer.setRGBA(x, y, src[bytesPerPixel * x + 0], src[bytesPerPixel * x + 1], src[bytesPerPixel * x + 2], 0xff);
137     }
138     m_lastVisibleRow = newLastVisibleRow;
139     if (m_lastVisibleRow == height)
140          buffer.setStatus(ImageFrame::FrameComplete);
141     return m_lastVisibleRow == height;
142 }
143 
144 }
145 
146 #endif
147