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      1 
      2 /*
      3  * Copyright 2010 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 SkPDFImage_DEFINED
     11 #define SkPDFImage_DEFINED
     12 
     13 #include "SkPicture.h"
     14 #include "SkPDFDevice.h"
     15 #include "SkPDFStream.h"
     16 #include "SkPDFTypes.h"
     17 #include "SkRefCnt.h"
     18 
     19 class SkBitmap;
     20 class SkData;
     21 class SkPDFCatalog;
     22 struct SkIRect;
     23 
     24 /**
     25  *  Return the mose efficient availible encoding of the given bitmap.
     26  *
     27  *  If the bitmap has encoded JPEG data and that data can be embedded
     28  *  into the PDF output stream directly, use that.  Otherwise, fall
     29  *  back on SkPDFImage::CreateImage.
     30  */
     31 SkPDFObject* SkPDFCreateImageObject(
     32         const SkBitmap&, const SkIRect& subset, SkPicture::EncodeBitmap);
     33 
     34 /** \class SkPDFImage
     35 
     36     An image XObject.
     37 */
     38 
     39 // We could play the same trick here as is done in SkPDFGraphicState, storing
     40 // a copy of the Bitmap object (not the pixels), the pixel generation number,
     41 // and settings used from the paint to canonicalize image objects.
     42 class SkPDFImage : public SkPDFStream {
     43 public:
     44     /** Create a new Image XObject to represent the passed bitmap.
     45      *  @param bitmap   The image to encode.
     46      *  @param srcRect  The rectangle to cut out of bitmap.
     47      *  @param paint    Used to calculate alpha, masks, etc.
     48      *  @return  The image XObject or NUll if there is nothing to draw for
     49      *           the given parameters.
     50      */
     51     static SkPDFImage* CreateImage(const SkBitmap& bitmap,
     52                                    const SkIRect& srcRect,
     53                                    SkPicture::EncodeBitmap encoder);
     54 
     55     virtual ~SkPDFImage();
     56 
     57     /** Add a Soft Mask (alpha or shape channel) to the image.  Refs mask.
     58      *  @param mask A gray scale image representing the mask.
     59      *  @return The mask argument is returned.
     60      */
     61     SkPDFImage* addSMask(SkPDFImage* mask);
     62 
     63     bool isEmpty() {
     64         return fSrcRect.isEmpty();
     65     }
     66 
     67     // The SkPDFObject interface.
     68     virtual void getResources(const SkTSet<SkPDFObject*>& knownResourceObjects,
     69                               SkTSet<SkPDFObject*>* newResourceObjects);
     70 
     71 private:
     72     SkBitmap fBitmap;
     73     bool fIsAlpha;
     74     SkIRect fSrcRect;
     75     SkPicture::EncodeBitmap fEncoder;
     76     bool fStreamValid;
     77 
     78     SkTDArray<SkPDFObject*> fResources;
     79 
     80     /** Create a PDF image XObject. Entries for the image properties are
     81      *  automatically added to the stream dictionary.
     82      *  @param stream     The image stream. May be NULL. Otherwise, this
     83      *                    (instead of the input bitmap) will be used as the
     84      *                    PDF's content stream, possibly with lossless encoding.
     85      *  @param bitmap     The image. If a stream is not given, its color data
     86      *                    will be used as the image. If a stream is given, this
     87      *                    is used for configuration only.
     88      *  @param isAlpha    Whether or not this is the alpha of an image.
     89      *  @param srcRect    The clipping applied to bitmap before generating
     90      *                    imageData.
     91      *  @param encoder    A function used to encode the bitmap for compression.
     92      *                    May be NULL.
     93      */
     94     SkPDFImage(SkStream* stream, const SkBitmap& bitmap, bool isAlpha,
     95                const SkIRect& srcRect, SkPicture::EncodeBitmap encoder);
     96 
     97     /** Copy constructor, used to generate substitutes.
     98      *  @param image      The SkPDFImage to copy.
     99      */
    100     SkPDFImage(SkPDFImage& pdfImage);
    101 
    102     // Populate the stream dictionary.  This method returns false if
    103     // fSubstitute should be used.
    104     virtual bool populate(SkPDFCatalog* catalog);
    105 
    106     typedef SkPDFStream INHERITED;
    107 };
    108 
    109 #endif
    110