1/*
2 * Copyright (C) 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 "WebImage.h"
33
34#include "Image.h"
35#include "ImageSource.h"
36#include "SharedBuffer.h"
37
38#include "WebData.h"
39#include "WebSize.h"
40
41#include <CoreGraphics/CGImage.h>
42
43#include <wtf/PassRefPtr.h>
44#include <wtf/RetainPtr.h>
45
46using namespace WebCore;
47
48namespace WebKit {
49
50WebImage WebImage::fromData(const WebData& data, const WebSize& desiredSize)
51{
52    ImageSource source;
53    source.setData(PassRefPtr<SharedBuffer>(data).get(), true);
54    if (!source.isSizeAvailable())
55        return WebImage();
56
57    // Frames are arranged by decreasing size, then decreasing bit depth.
58    // Pick the frame closest to |desiredSize|'s area without being smaller,
59    // which has the highest bit depth.
60    const size_t frameCount = source.frameCount();
61    size_t index = 0; // Default to first frame if none are large enough.
62    int frameAreaAtIndex = 0;
63    for (size_t i = 0; i < frameCount; ++i) {
64        const IntSize frameSize = source.frameSizeAtIndex(i);
65        if (WebSize(frameSize) == desiredSize) {
66            index = i;
67            break; // Perfect match.
68        }
69        const int frameArea = frameSize.width() * frameSize.height();
70        if (frameArea < (desiredSize.width * desiredSize.height))
71            break; // No more frames that are large enough.
72
73        if (!i || (frameArea < frameAreaAtIndex)) {
74            index = i; // Closer to desired area than previous best match.
75            frameAreaAtIndex = frameArea;
76        }
77    }
78
79    RetainPtr<CGImageRef> frame(AdoptCF, source.createFrameAtIndex(index));
80    if (!frame)
81        return WebImage();
82
83    return WebImage(frame.get());
84}
85
86void WebImage::reset()
87{
88    CGImageRelease(m_imageRef);
89    m_imageRef = 0;
90}
91
92void WebImage::assign(const WebImage& image)
93{
94    assign(image.m_imageRef);
95}
96
97bool WebImage::isNull() const
98{
99    return !m_imageRef;
100}
101
102WebSize WebImage::size() const
103{
104    return WebSize(CGImageGetWidth(m_imageRef), CGImageGetHeight(m_imageRef));
105}
106
107WebImage::WebImage(const PassRefPtr<Image>& image)
108    : m_imageRef(0)
109{
110    NativeImagePtr p;
111    if (image.get() && (p = image->nativeImageForCurrentFrame()))
112        assign(p);
113}
114
115WebImage& WebImage::operator=(const PassRefPtr<Image>& image)
116{
117    NativeImagePtr p;
118    if (image.get() && (p = image->nativeImageForCurrentFrame()))
119        assign(p);
120    else
121        reset();
122    return *this;
123}
124
125void WebImage::assign(CGImageRef imageRef)
126{
127    // Make sure to retain the imageRef first incase m_imageRef == imageRef.
128    CGImageRetain(imageRef);
129    CGImageRelease(m_imageRef);
130    m_imageRef = imageRef;
131}
132
133} // namespace WebKit
134