1 /* 2 * Copyright (C) 2008 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #ifndef SkImageRef_DEFINED 18 #define SkImageRef_DEFINED 19 20 #include "SkPixelRef.h" 21 #include "SkBitmap.h" 22 #include "SkImageDecoder.h" 23 #include "SkString.h" 24 25 class SkImageRefPool; 26 class SkStream; 27 28 // define this to enable dumping whenever we add/remove/purge an imageref 29 //#define DUMP_IMAGEREF_LIFECYCLE 30 31 class SkImageRef : public SkPixelRef { 32 public: 33 /** Create a new imageref from a stream. NOTE: the stream is not copied, but 34 since it may be accessed from another thread, the caller must ensure 35 that this imageref is the only owner of the stream. i.e. - sole 36 ownership of the stream object is transferred to this imageref object. 37 38 @param stream The stream containing the encoded image data. This may be 39 retained (by calling ref()), so the caller should not 40 explicitly delete it. 41 @param config The preferred config of the decoded bitmap. 42 @param sampleSize Requested sampleSize for decoding. Defaults to 1. 43 */ 44 SkImageRef(SkStream*, SkBitmap::Config config, int sampleSize = 1); 45 virtual ~SkImageRef(); 46 47 /** this value is passed onto the decoder. Default is true 48 */ setDitherImage(bool dither)49 void setDitherImage(bool dither) { fDoDither = dither; } 50 51 /** Return true if the image can be decoded. If so, and bitmap is non-null, 52 call its setConfig() with the corresponding values, but explicitly will 53 not set its pixels or colortable. Use SkPixelRef::lockPixels() for that. 54 55 If there has been an error decoding the bitmap, this will return false 56 and ignore the bitmap parameter. 57 */ 58 bool getInfo(SkBitmap* bm); 59 60 /** Return true if the image can be decoded and is opaque. Calling this 61 method will decode and set the pixels in the specified bitmap and 62 set the opaque flag. 63 */ 64 bool isOpaque(SkBitmap* bm); 65 getDecoderFactory()66 SkImageDecoderFactory* getDecoderFactory() const { return fFactory; } 67 // returns the factory parameter 68 SkImageDecoderFactory* setDecoderFactory(SkImageDecoderFactory*); 69 70 // overrides 71 virtual void flatten(SkFlattenableWriteBuffer&) const; 72 73 protected: 74 /** Override if you want to install a custom allocator. 75 When this is called we will have already acquired the mutex! 76 */ 77 virtual bool onDecode(SkImageDecoder* codec, SkStream*, SkBitmap*, 78 SkBitmap::Config, SkImageDecoder::Mode); 79 80 /* Overrides from SkPixelRef 81 When these are called, we will have already acquired the mutex! 82 */ 83 84 virtual void* onLockPixels(SkColorTable**); 85 // override this in your subclass to clean up when we're unlocking pixels 86 virtual void onUnlockPixels(); 87 88 SkImageRef(SkFlattenableReadBuffer&); 89 90 SkBitmap fBitmap; 91 92 private: 93 SkStream* setStream(SkStream*); 94 // called with mutex already held. returns true if the bitmap is in the 95 // requested state (or further, i.e. has pixels) 96 bool prepareBitmap(SkImageDecoder::Mode); 97 98 SkImageDecoderFactory* fFactory; // may be null 99 SkStream* fStream; 100 SkBitmap::Config fConfig; 101 int fSampleSize; 102 bool fDoDither; 103 bool fErrorInDecoding; 104 105 friend class SkImageRefPool; 106 107 SkImageRef* fPrev, *fNext; 108 size_t ramUsed() const; 109 110 typedef SkPixelRef INHERITED; 111 }; 112 113 #endif 114