File: WEBPImageDecoder.cpp

package info (click to toggle)
webkit 1.8.1-3.4
  • links: PTS, VCS
  • area: main
  • in suites: wheezy
  • size: 86,872 kB
  • sloc: cpp: 748,063; ansic: 17,151; sh: 11,084; perl: 10,883; yacc: 3,678; python: 3,440; lex: 559; makefile: 168; xml: 91
file content (150 lines) | stat: -rw-r--r-- 4,880 bytes parent folder | download
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
/*
 * Copyright (C) 2010 Google Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1.  Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 * 2.  Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
 *     its contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include "config.h"
#include "WEBPImageDecoder.h"

#if USE(WEBP)

#include "webp/decode.h"

#if PLATFORM(CHROMIUM)
#include "TraceEvent.h"
#endif

#if CPU(BIG_ENDIAN) || CPU(MIDDLE_ENDIAN)
inline WEBP_CSP_MODE outputMode() { return MODE_RGBA; }
#else // LITTLE_ENDIAN, output BGRA pixels.
inline WEBP_CSP_MODE outputMode() { return MODE_BGRA; }
#endif

namespace WebCore {

WEBPImageDecoder::WEBPImageDecoder(ImageSource::AlphaOption alphaOption,
                                   ImageSource::GammaAndColorProfileOption gammaAndColorProfileOption)
    : ImageDecoder(alphaOption, gammaAndColorProfileOption)
    , m_decoder(0)
{
}

WEBPImageDecoder::~WEBPImageDecoder()
{
    if (m_decoder)
        WebPIDelete(m_decoder);
    m_decoder = 0;
}

bool WEBPImageDecoder::isSizeAvailable()
{
    if (!ImageDecoder::isSizeAvailable())
         decode(true);

    return ImageDecoder::isSizeAvailable();
}

ImageFrame* WEBPImageDecoder::frameBufferAtIndex(size_t index)
{
    if (index)
        return 0;

    if (m_frameBufferCache.isEmpty()) {
        m_frameBufferCache.resize(1);
        m_frameBufferCache[0].setPremultiplyAlpha(m_premultiplyAlpha);
    }

    ImageFrame& frame = m_frameBufferCache[0];
    if (frame.status() != ImageFrame::FrameComplete)
        decode(false);
    return &frame;
}

bool WEBPImageDecoder::decode(bool onlySize)
{
#if PLATFORM(CHROMIUM)
    TRACE_EVENT("WEBPImageDecoder::decode", this, 0);
#endif
    if (failed())
        return false;

    const uint8_t* dataBytes = reinterpret_cast<const uint8_t*>(m_data->data());
    const size_t dataSize = m_data->size();

    if (!ImageDecoder::isSizeAvailable()) {
        static const size_t imageHeaderSize = 30;
        if (dataSize < imageHeaderSize)
            return false;
        int width, height;
        if (!WebPGetInfo(dataBytes, dataSize, &width, &height))
            return setFailed();
        if (!setSize(width, height))
            return setFailed();
    }

    ASSERT(ImageDecoder::isSizeAvailable());
    if (onlySize)
        return true;

    ASSERT(!m_frameBufferCache.isEmpty());
    ImageFrame& buffer = m_frameBufferCache[0];
    ASSERT(buffer.status() != ImageFrame::FrameComplete);

    if (buffer.status() == ImageFrame::FrameEmpty) {
        if (!buffer.setSize(size().width(), size().height()))
            return setFailed();
        buffer.setStatus(ImageFrame::FramePartial);
        buffer.setHasAlpha(false); // FIXME: webp does not support alpha yet.
        buffer.setOriginalFrameRect(IntRect(IntPoint(), size()));
    }

    if (!m_decoder) {
        int rowStride = size().width() * sizeof(ImageFrame::PixelData);
        uint8_t* output = reinterpret_cast<uint8_t*>(buffer.getAddr(0, 0));
        int outputSize = size().height() * rowStride;
        m_decoder = WebPINewRGB(outputMode(), output, outputSize, rowStride);
        if (!m_decoder)
            return setFailed();
    }

    switch (WebPIUpdate(m_decoder, dataBytes, dataSize)) {
    case VP8_STATUS_OK:
        buffer.setStatus(ImageFrame::FrameComplete);
        WebPIDelete(m_decoder);
        m_decoder = 0;
        return true;
    case VP8_STATUS_SUSPENDED:
        return false;
    default:
        WebPIDelete(m_decoder);
        m_decoder = 0;
        return setFailed();
    }
}

} // namespace WebCore

#endif