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 35 namespace blink { 36 37 class DeferredImageDecoder; 38 class ImageOrientation; 39 class IntPoint; 40 class IntSize; 41 class NativeImageSkia; 42 class SharedBuffer; 43 44 // GIF and WebP support animation. The explanation below is in terms of GIF, 45 // but the same constants are used for WebP, too. 46 // GIFs have an optional 16-bit unsigned loop count that describes how an 47 // animated GIF should be cycled. If the loop count is absent, the animation 48 // cycles once; if it is 0, the animation cycles infinitely; otherwise the 49 // animation plays n + 1 cycles (where n is the specified loop count). If the 50 // GIF decoder defaults to cAnimationLoopOnce in the absence of any loop count 51 // and translates an explicit "0" loop count to cAnimationLoopInfinite, then we 52 // get a couple of nice side effects: 53 // * By making cAnimationLoopOnce be 0, we allow the animation cycling code in 54 // BitmapImage.cpp to avoid special-casing it, and simply treat all 55 // non-negative loop counts identically. 56 // * By making the other two constants negative, we avoid conflicts with any 57 // real loop count values. 58 const int cAnimationLoopOnce = 0; 59 const int cAnimationLoopInfinite = -1; 60 const int cAnimationNone = -2; 61 62 class PLATFORM_EXPORT ImageSource { 63 WTF_MAKE_NONCOPYABLE(ImageSource); 64 public: 65 enum AlphaOption { 66 AlphaPremultiplied, 67 AlphaNotPremultiplied 68 }; 69 70 enum GammaAndColorProfileOption { 71 GammaAndColorProfileApplied, 72 GammaAndColorProfileIgnored 73 }; 74 75 ImageSource(AlphaOption alphaOption = AlphaPremultiplied, GammaAndColorProfileOption gammaAndColorProfileOption = GammaAndColorProfileApplied); 76 ~ImageSource(); 77 78 // Tells the ImageSource that the Image no longer cares about decoded frame 79 // data except for the specified frame. Callers may pass WTF::kNotFound to 80 // clear all frames. 81 // 82 // In response, the ImageSource should delete cached decoded data for other 83 // frames where possible to keep memory use low. The expectation is that in 84 // the future, the caller may call createFrameAtIndex() with an index larger 85 // than the one passed to this function, and the implementation may then 86 // make use of the preserved frame data here in decoding that frame. 87 // By contrast, callers who call this function and then later ask for an 88 // earlier frame may require more work to be done, e.g. redecoding the image 89 // from the beginning. 90 // 91 // Implementations may elect to preserve more frames than the one requested 92 // here if doing so is likely to save CPU time in the future, but will pay 93 // an increased memory cost to do so. 94 // 95 // Returns the number of bytes of frame data actually cleared. 96 size_t clearCacheExceptFrame(size_t); 97 98 bool initialized() const; 99 void resetDecoder(); 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 } // namespace blink 137 138 #endif 139
