1 /* 2 * Copyright (C) 2004, 2005, 2006 Apple Computer, 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 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 13 * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY 14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 16 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE COMPUTER, INC. OR 17 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 18 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 19 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 20 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY 21 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 23 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 24 */ 25 26 #ifndef ImageSource_h 27 #define ImageSource_h 28 29 #include "platform/PlatformExport.h" 30 #include "platform/graphics/ImageOrientation.h" 31 #include "wtf/Forward.h" 32 #include "wtf/Noncopyable.h" 33 #include "wtf/OwnPtr.h" 34 #include "wtf/Vector.h" 35 36 namespace WebCore { 37 38 class DeferredImageDecoder; 39 class ImageOrientation; 40 class IntPoint; 41 class IntSize; 42 class NativeImageSkia; 43 class SharedBuffer; 44 45 // GIF and WebP support animation. The explanation below is in terms of GIF, 46 // but the same constants are used for WebP, too. 47 // GIFs have an optional 16-bit unsigned loop count that describes how an 48 // animated GIF should be cycled. If the loop count is absent, the animation 49 // cycles once; if it is 0, the animation cycles infinitely; otherwise the 50 // animation plays n + 1 cycles (where n is the specified loop count). If the 51 // GIF decoder defaults to cAnimationLoopOnce in the absence of any loop count 52 // and translates an explicit "0" loop count to cAnimationLoopInfinite, then we 53 // get a couple of nice side effects: 54 // * By making cAnimationLoopOnce be 0, we allow the animation cycling code in 55 // BitmapImage.cpp to avoid special-casing it, and simply treat all 56 // non-negative loop counts identically. 57 // * By making the other two constants negative, we avoid conflicts with any 58 // real loop count values. 59 const int cAnimationLoopOnce = 0; 60 const int cAnimationLoopInfinite = -1; 61 const int cAnimationNone = -2; 62 63 class PLATFORM_EXPORT ImageSource { 64 WTF_MAKE_NONCOPYABLE(ImageSource); 65 public: 66 enum AlphaOption { 67 AlphaPremultiplied, 68 AlphaNotPremultiplied 69 }; 70 71 enum GammaAndColorProfileOption { 72 GammaAndColorProfileApplied, 73 GammaAndColorProfileIgnored 74 }; 75 76 ImageSource(AlphaOption alphaOption = AlphaPremultiplied, GammaAndColorProfileOption gammaAndColorProfileOption = GammaAndColorProfileApplied); 77 ~ImageSource(); 78 79 // Tells the ImageSource that the Image no longer cares about decoded frame 80 // data except for the specified frame. Callers may pass WTF::kNotFound to 81 // clear all frames. 82 // 83 // In response, the ImageSource should delete cached decoded data for other 84 // frames where possible to keep memory use low. The expectation is that in 85 // the future, the caller may call createFrameAtIndex() with an index larger 86 // than the one passed to this function, and the implementation may then 87 // make use of the preserved frame data here in decoding that frame. 88 // By contrast, callers who call this function and then later ask for an 89 // earlier frame may require more work to be done, e.g. redecoding the image 90 // from the beginning. 91 // 92 // Implementations may elect to preserve more frames than the one requested 93 // here if doing so is likely to save CPU time in the future, but will pay 94 // an increased memory cost to do so. 95 // 96 // Returns the number of bytes of frame data actually cleared. 97 size_t clearCacheExceptFrame(size_t); 98 99 bool initialized() const; 100 101 void setData(SharedBuffer& data, bool allDataReceived); 102 String filenameExtension() const; 103 104 bool isSizeAvailable(); 105 bool hasColorProfile() const; 106 IntSize size(RespectImageOrientationEnum = DoNotRespectImageOrientation) const; 107 IntSize frameSizeAtIndex(size_t, RespectImageOrientationEnum = DoNotRespectImageOrientation) const; 108 109 bool getHotSpot(IntPoint&) const; 110 111 // Returns one of the cAnimationXXX constants at the top of the file, or 112 // a loop count. In the latter case, the actual number of times the animation 113 // cycles is one more than the loop count. See comment atop the file. 114 int repetitionCount(); 115 116 size_t frameCount() const; 117 118 PassRefPtr<NativeImageSkia> createFrameAtIndex(size_t); 119 120 float frameDurationAtIndex(size_t) const; 121 bool frameHasAlphaAtIndex(size_t) const; // Whether or not the frame actually used any alpha. 122 bool frameIsCompleteAtIndex(size_t) const; // Whether or not the frame is fully received. 123 ImageOrientation orientationAtIndex(size_t) const; // EXIF image orientation 124 125 // Return the number of bytes in the decoded frame. If the frame is not yet 126 // decoded then return 0. 127 unsigned frameBytesAtIndex(size_t) const; 128 129 private: 130 OwnPtr<DeferredImageDecoder> m_decoder; 131 132 AlphaOption m_alphaOption; 133 GammaAndColorProfileOption m_gammaAndColorProfileOption; 134 }; 135 136 } 137 138 #endif 139
