1 2 /* 3 * Copyright 2008 The Android Open Source Project 4 * 5 * Use of this source code is governed by a BSD-style license that can be 6 * found in the LICENSE file. 7 */ 8 9 10 #ifndef SkImageRef_DEFINED 11 #define SkImageRef_DEFINED 12 13 #include "SkPixelRef.h" 14 #include "SkBitmap.h" 15 #include "SkImageDecoder.h" 16 #include "SkString.h" 17 18 class SkImageRefPool; 19 class SkStream; 20 21 // define this to enable dumping whenever we add/remove/purge an imageref 22 //#define DUMP_IMAGEREF_LIFECYCLE 23 24 class SkImageRef : public SkPixelRef { 25 public: 26 /** Create a new imageref from a stream. NOTE: the stream is not copied, but 27 since it may be accessed from another thread, the caller must ensure 28 that this imageref is the only owner of the stream. i.e. - sole 29 ownership of the stream object is transferred to this imageref object. 30 31 @param stream The stream containing the encoded image data. This may be 32 retained (by calling ref()), so the caller should not 33 explicitly delete it. 34 @param config The preferred config of the decoded bitmap. 35 @param sampleSize Requested sampleSize for decoding. Defaults to 1. 36 */ 37 SkImageRef(SkStream*, SkBitmap::Config config, int sampleSize = 1); 38 virtual ~SkImageRef(); 39 40 /** this value is passed onto the decoder. Default is true 41 */ setDitherImage(bool dither)42 void setDitherImage(bool dither) { fDoDither = dither; } 43 44 /** Return true if the image can be decoded. If so, and bitmap is non-null, 45 call its setConfig() with the corresponding values, but explicitly will 46 not set its pixels or colortable. Use SkPixelRef::lockPixels() for that. 47 48 If there has been an error decoding the bitmap, this will return false 49 and ignore the bitmap parameter. 50 */ 51 bool getInfo(SkBitmap* bm); 52 53 /** Return true if the image can be decoded and is opaque. Calling this 54 method will decode and set the pixels in the specified bitmap and 55 sets the isOpaque flag. 56 */ 57 bool isOpaque(SkBitmap* bm); 58 getDecoderFactory()59 SkImageDecoderFactory* getDecoderFactory() const { return fFactory; } 60 // returns the factory parameter 61 SkImageDecoderFactory* setDecoderFactory(SkImageDecoderFactory*); 62 63 // overrides 64 virtual void flatten(SkFlattenableWriteBuffer&) const; 65 66 protected: 67 /** Override if you want to install a custom allocator. 68 When this is called we will have already acquired the mutex! 69 */ 70 virtual bool onDecode(SkImageDecoder* codec, SkStream*, SkBitmap*, 71 SkBitmap::Config, SkImageDecoder::Mode); 72 73 /* Overrides from SkPixelRef 74 When these are called, we will have already acquired the mutex! 75 */ 76 77 virtual void* onLockPixels(SkColorTable**); 78 // override this in your subclass to clean up when we're unlocking pixels 79 virtual void onUnlockPixels(); 80 81 SkImageRef(SkFlattenableReadBuffer&); 82 83 SkBitmap fBitmap; 84 85 private: 86 SkStream* setStream(SkStream*); 87 // called with mutex already held. returns true if the bitmap is in the 88 // requested state (or further, i.e. has pixels) 89 bool prepareBitmap(SkImageDecoder::Mode); 90 91 SkImageDecoderFactory* fFactory; // may be null 92 SkStream* fStream; 93 SkBitmap::Config fConfig; 94 int fSampleSize; 95 bool fDoDither; 96 bool fErrorInDecoding; 97 98 friend class SkImageRefPool; 99 100 SkImageRef* fPrev, *fNext; 101 size_t ramUsed() const; 102 103 typedef SkPixelRef INHERITED; 104 }; 105 106 #endif 107