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      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 
     46 using namespace WebCore;
     47 
     48 namespace WebKit {
     49 
     50 WebImage 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 
     86 void WebImage::reset()
     87 {
     88     CGImageRelease(m_imageRef);
     89     m_imageRef = 0;
     90 }
     91 
     92 void WebImage::assign(const WebImage& image)
     93 {
     94     assign(image.m_imageRef);
     95 }
     96 
     97 bool WebImage::isNull() const
     98 {
     99     return !m_imageRef;
    100 }
    101 
    102 WebSize WebImage::size() const
    103 {
    104     return WebSize(CGImageGetWidth(m_imageRef), CGImageGetHeight(m_imageRef));
    105 }
    106 
    107 WebImage::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 
    115 WebImage& 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 
    125 void 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