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Diffstat (limited to 'include/core/SkImageDecoder.h')
-rw-r--r-- | include/core/SkImageDecoder.h | 413 |
1 files changed, 0 insertions, 413 deletions
diff --git a/include/core/SkImageDecoder.h b/include/core/SkImageDecoder.h deleted file mode 100644 index 7a90964b13..0000000000 --- a/include/core/SkImageDecoder.h +++ /dev/null @@ -1,413 +0,0 @@ -/* - * Copyright 2006 The Android Open Source Project - * - * Use of this source code is governed by a BSD-style license that can be - * found in the LICENSE file. - */ - -#ifndef SkImageDecoder_DEFINED -#define SkImageDecoder_DEFINED - -#include "SkBitmap.h" -#include "SkImage.h" -#include "SkPngChunkReader.h" -#include "SkRect.h" -#include "SkRefCnt.h" -#include "SkTRegistry.h" -#include "SkTypes.h" - -class SkStream; -class SkStreamRewindable; - -/** \class SkImageDecoder - - DEPRECATED Please use SkImage::NewFromEncoded() or SkImageGenerator::NewFromEncoded(). - - Base class for decoding compressed images into a SkBitmap -*/ -class SkImageDecoder : SkNoncopyable { -public: - virtual ~SkImageDecoder(); - - // TODO (scroggo): Merge with SkEncodedFormat - enum Format { - kUnknown_Format, - kBMP_Format, - kGIF_Format, - kICO_Format, - kJPEG_Format, - kPNG_Format, - kWBMP_Format, - kWEBP_Format, - kPKM_Format, - kKTX_Format, - kASTC_Format, - - kLastKnownFormat = kKTX_Format, - }; - - /** Return the format of image this decoder can decode. If this decoder can decode multiple - formats, kUnknown_Format will be returned. - */ - virtual Format getFormat() const; - - /** If planes or rowBytes is NULL, decodes the header and computes componentSizes - for memory allocation. - Otherwise, decodes the YUV planes into the provided image planes and - updates componentSizes to the final image size. - Returns whether the decoding was successful. - */ - bool decodeYUV8Planes(SkStream* stream, SkISize componentSizes[3], void* planes[3], - size_t rowBytes[3], SkYUVColorSpace*); - - /** Return the format of the SkStreamRewindable or kUnknown_Format if it cannot be determined. - Rewinds the stream before returning. - */ - static Format GetStreamFormat(SkStreamRewindable*); - - /** Return a readable string of the Format provided. - */ - static const char* GetFormatName(Format); - - /** Return a readable string of the value returned by getFormat(). - */ - const char* getFormatName() const; - - /** Whether the decoder should skip writing zeroes to output if possible. - */ - bool getSkipWritingZeroes() const { return fSkipWritingZeroes; } - - /** Set to true if the decoder should skip writing any zeroes when - creating the output image. - This is a hint that may not be respected by the decoder. - It should only be used if it is known that the memory to write - to has already been set to 0; otherwise the resulting image will - have garbage. - This is ideal for images that contain a lot of completely transparent - pixels, but may be a performance hit for an image that has only a - few transparent pixels. - The default is false. - */ - void setSkipWritingZeroes(bool skip) { fSkipWritingZeroes = skip; } - - /** Returns true if the decoder should try to dither the resulting image. - The default setting is true. - */ - bool getDitherImage() const { return fDitherImage; } - - /** Set to true if the the decoder should try to dither the resulting image. - The default setting is true. - */ - void setDitherImage(bool dither) { fDitherImage = dither; } - - /** Returns true if the decoder should try to decode the - resulting image to a higher quality even at the expense of - the decoding speed. - */ - bool getPreferQualityOverSpeed() const { return fPreferQualityOverSpeed; } - - /** Set to true if the the decoder should try to decode the - resulting image to a higher quality even at the expense of - the decoding speed. - */ - void setPreferQualityOverSpeed(bool qualityOverSpeed) { - fPreferQualityOverSpeed = qualityOverSpeed; - } - - /** Set to true to require the decoder to return a bitmap with unpremultiplied - colors. The default is false, meaning the resulting bitmap will have its - colors premultiplied. - NOTE: Passing true to this function may result in a bitmap which cannot - be properly used by Skia. - */ - void setRequireUnpremultipliedColors(bool request) { - fRequireUnpremultipliedColors = request; - } - - /** Returns true if the decoder will only return bitmaps with unpremultiplied - colors. - */ - bool getRequireUnpremultipliedColors() const { return fRequireUnpremultipliedColors; } - - SkPngChunkReader* getPeeker() const { return fPeeker; } - SkPngChunkReader* setPeeker(SkPngChunkReader*); - - /** - * By default, the codec will try to comply with the "pref" colortype - * that is passed to decode() or decodeSubset(). However, this can be called - * to override that, causing the codec to try to match the src depth instead - * (as shown below). - * - * src_8Index -> kIndex_8_SkColorType - * src_8Gray -> kN32_SkColorType - * src_8bpc -> kN32_SkColorType - */ - void setPreserveSrcDepth(bool preserve) { - fPreserveSrcDepth = preserve; - } - - SkBitmap::Allocator* getAllocator() const { return fAllocator; } - SkBitmap::Allocator* setAllocator(SkBitmap::Allocator*); - - // sample-size, if set to > 1, tells the decoder to return a smaller than - // original bitmap, sampling 1 pixel for every size pixels. e.g. if sample - // size is set to 3, then the returned bitmap will be 1/3 as wide and high, - // and will contain 1/9 as many pixels as the original. - // Note: this is a hint, and the codec may choose to ignore this, or only - // approximate the sample size. - int getSampleSize() const { return fSampleSize; } - void setSampleSize(int size); - - /** Reset the sampleSize to its default of 1 - */ - void resetSampleSize() { this->setSampleSize(1); } - - /** Decoding is synchronous, but for long decodes, a different thread can - call this method safely. This sets a state that the decoders will - periodically check, and if they see it changed to cancel, they will - cancel. This will result in decode() returning false. However, there is - no guarantee that the decoder will see the state change in time, so - it is possible that cancelDecode() will be called, but will be ignored - and decode() will return true (assuming no other problems were - encountered). - - This state is automatically reset at the beginning of decode(). - */ - void cancelDecode() { - // now the subclass must query shouldCancelDecode() to be informed - // of the request - fShouldCancelDecode = true; - } - - /** Passed to the decode method. If kDecodeBounds_Mode is passed, then - only the bitmap's info need be set. If kDecodePixels_Mode - is passed, then the bitmap must have pixels or a pixelRef. - */ - enum Mode { - kDecodeBounds_Mode, //!< only return info in bitmap - kDecodePixels_Mode //!< return entire bitmap (including pixels) - }; - - /** Result of a decode. If read as a boolean, a partial success is - considered a success (true). - */ - enum Result { - kFailure = 0, //!< Image failed to decode. bitmap will be - // unchanged. - kPartialSuccess = 1, //!< Part of the image decoded. The rest is - // filled in automatically - kSuccess = 2 //!< The entire image was decoded, if Mode is - // kDecodePixels_Mode, or the bounds were - // decoded, in kDecodeBounds_Mode. - }; - - /** Given a stream, decode it into the specified bitmap. - If the decoder can decompress the image, it calls bitmap.setInfo(), - and then if the Mode is kDecodePixels_Mode, call allocPixelRef(), - which will allocated a pixelRef. To access the pixel memory, the codec - needs to call lockPixels/unlockPixels on the - bitmap. It can then set the pixels with the decompressed image. - * If the image cannot be decompressed, return kFailure. After the - * decoding, the function converts the decoded colortype in bitmap - * to pref if possible. Whether a conversion is feasible is - * tested by Bitmap::canCopyTo(pref). - - If an SkBitmap::Allocator is installed via setAllocator, it will be - used to allocate the pixel memory. A clever allocator can be used - to allocate the memory from a cache, volatile memory, or even from - an existing bitmap's memory. - - If an SkPngChunkReader is installed via setPeeker, it may be used to - peek into meta data during the decode. - */ - Result decode(SkStream*, SkBitmap* bitmap, SkColorType pref, Mode); - Result decode(SkStream* stream, SkBitmap* bitmap, Mode mode) { - return this->decode(stream, bitmap, kUnknown_SkColorType, mode); - } - - /** Given a stream, this will try to find an appropriate decoder object. - If none is found, the method returns NULL. - - DEPRECATED Please use SkImage::NewFromEncoded() or SkImageGenerator::NewFromEncoded(). - */ - static SkImageDecoder* Factory(SkStreamRewindable*); - - /** Decode the image stored in the specified file, and store the result - in bitmap. Return true for success or false on failure. - - @param pref Prefer this colortype. - - @param format On success, if format is non-null, it is set to the format - of the decoded file. On failure it is ignored. - - DEPRECATED Do not use. - */ - static bool DecodeFile(const char file[], SkBitmap* bitmap, SkColorType pref, Mode, - Format* format = NULL); - static bool DecodeFile(const char file[], SkBitmap* bitmap) { - return DecodeFile(file, bitmap, kUnknown_SkColorType, kDecodePixels_Mode, NULL); - } - - /** Decode the image stored in the specified memory buffer, and store the - result in bitmap. Return true for success or false on failure. - - @param pref Prefer this colortype. - - @param format On success, if format is non-null, it is set to the format - of the decoded buffer. On failure it is ignored. - - DEPRECATED Please use SkImage::NewFromEncoded() or SkImageGenerator::NewFromEncoded(). - */ - static bool DecodeMemory(const void* buffer, size_t size, SkBitmap* bitmap, SkColorType pref, - Mode, Format* format = NULL); - static bool DecodeMemory(const void* buffer, size_t size, SkBitmap* bitmap){ - return DecodeMemory(buffer, size, bitmap, kUnknown_SkColorType, kDecodePixels_Mode, NULL); - } - - /** Decode the image stored in the specified SkStreamRewindable, and store the result - in bitmap. Return true for success or false on failure. - - @param pref Prefer this colortype. - - @param format On success, if format is non-null, it is set to the format - of the decoded stream. On failure it is ignored. - - DEPRECATED Please use SkImage::NewFromEncoded() or SkImageGenerator::NewFromEncoded(). - */ - static bool DecodeStream(SkStreamRewindable* stream, SkBitmap* bitmap, SkColorType pref, Mode, - Format* format = NULL); - static bool DecodeStream(SkStreamRewindable* stream, SkBitmap* bitmap) { - return DecodeStream(stream, bitmap, kUnknown_SkColorType, kDecodePixels_Mode, NULL); - } - -protected: - // must be overridden in subclasses. This guy is called by decode(...) - virtual Result onDecode(SkStream*, SkBitmap* bitmap, Mode) = 0; - - /** If planes or rowBytes is NULL, decodes the header and computes componentSizes - for memory allocation. - Otherwise, decodes the YUV planes into the provided image planes and - updates componentSizes to the final image size. - Returns whether the decoding was successful. - */ - virtual bool onDecodeYUV8Planes(SkStream*, SkISize[3] /*componentSizes*/, - void*[3] /*planes*/, size_t[3] /*rowBytes*/, - SkYUVColorSpace*) { - return false; - } - - /** - * Copy all fields on this decoder to the other decoder. Used by subclasses - * to decode a subimage using a different decoder, but with the same settings. - */ - void copyFieldsToOther(SkImageDecoder* other); - - /** Can be queried from within onDecode, to see if the user (possibly in - a different thread) has requested the decode to cancel. If this returns - true, your onDecode() should stop and return false. - Each subclass needs to decide how often it can query this, to balance - responsiveness with performance. - - Calling this outside of onDecode() may return undefined values. - */ - -public: - bool shouldCancelDecode() const { return fShouldCancelDecode; } - -protected: - SkImageDecoder(); - - /** - * Return the default preference being used by the current or latest call to decode. - */ - SkColorType getDefaultPref() { return fDefaultPref; } - - /* Helper for subclasses. Call this to allocate the pixel memory given the bitmap's info. - Returns true on success. This method handles checking for an optional Allocator. - */ - bool allocPixelRef(SkBitmap*, SkColorTable*) const; - - /** - * The raw data of the src image. - */ - enum SrcDepth { - // Color-indexed. - kIndex_SrcDepth, - // Grayscale in 8 bits. - k8BitGray_SrcDepth, - // 8 bits per component. Used for 24 bit if there is no alpha. - k32Bit_SrcDepth, - }; - /** The subclass, inside onDecode(), calls this to determine the colorType of - the returned bitmap. SrcDepth and hasAlpha reflect the raw data of the - src image. This routine returns the caller's preference given - srcDepth and hasAlpha, or kUnknown_SkColorType if there is no preference. - */ - SkColorType getPrefColorType(SrcDepth, bool hasAlpha) const; - -private: - SkPngChunkReader* fPeeker; - SkBitmap::Allocator* fAllocator; - int fSampleSize; - SkColorType fDefaultPref; // use if fUsePrefTable is false - bool fPreserveSrcDepth; - bool fDitherImage; - bool fSkipWritingZeroes; - mutable bool fShouldCancelDecode; - bool fPreferQualityOverSpeed; - bool fRequireUnpremultipliedColors; -}; - -/** Calling newDecoder with a stream returns a new matching imagedecoder - instance, or NULL if none can be found. The caller must manage its ownership - of the stream as usual, calling unref() when it is done, as the returned - decoder may have called ref() (and if so, the decoder is responsible for - balancing its ownership when it is destroyed). - */ -class SkImageDecoderFactory : public SkRefCnt { -public: - - - virtual SkImageDecoder* newDecoder(SkStreamRewindable*) = 0; - -private: - typedef SkRefCnt INHERITED; -}; - -class SkDefaultImageDecoderFactory : SkImageDecoderFactory { -public: - // calls SkImageDecoder::Factory(stream) - virtual SkImageDecoder* newDecoder(SkStreamRewindable* stream) { - return SkImageDecoder::Factory(stream); - } -}; - -// This macro declares a global (i.e., non-class owned) creation entry point -// for each decoder (e.g., CreateJPEGImageDecoder) -#define DECLARE_DECODER_CREATOR(codec) \ - SkImageDecoder *Create ## codec (); - -// This macro defines the global creation entry point for each decoder. Each -// decoder implementation that registers with the decoder factory must call it. -#define DEFINE_DECODER_CREATOR(codec) \ - SkImageDecoder* Create##codec() { return new Sk##codec; } - -// All the decoders known by Skia. Note that, depending on the compiler settings, -// not all of these will be available -DECLARE_DECODER_CREATOR(BMPImageDecoder); -DECLARE_DECODER_CREATOR(GIFImageDecoder); -DECLARE_DECODER_CREATOR(ICOImageDecoder); -DECLARE_DECODER_CREATOR(JPEGImageDecoder); -DECLARE_DECODER_CREATOR(PNGImageDecoder); -DECLARE_DECODER_CREATOR(WBMPImageDecoder); -DECLARE_DECODER_CREATOR(WEBPImageDecoder); -DECLARE_DECODER_CREATOR(PKMImageDecoder); -DECLARE_DECODER_CREATOR(KTXImageDecoder); -DECLARE_DECODER_CREATOR(ASTCImageDecoder); - -// Typedefs to make registering decoder and formatter callbacks easier. -// These have to be defined outside SkImageDecoder. :( -typedef SkTRegistry<SkImageDecoder*(*)(SkStreamRewindable*)> SkImageDecoder_DecodeReg; -typedef SkTRegistry<SkImageDecoder::Format(*)(SkStreamRewindable*)> SkImageDecoder_FormatReg; - -#endif |