bufferedimage.java

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        case TYPE_BYTE_INDEXED:
            {
                // Create a 6x6x6 color cube
                int[] cmap = new int[256];
                int i=0;
                for (int r=0; r < 256; r += 51) {
                    for (int g=0; g < 256; g += 51) {
                        for (int b=0; b < 256; b += 51) {
                            cmap[i++] = (r<<16)|(g<<8)|b;
                        }
                    }
                }
                // And populate the rest of the cmap with gray values
                int grayIncr = 256/(256-i);
                
                // The gray ramp will be between 18 and 252
                int gray = grayIncr*3;
                for (; i < 256; i++) {
                    cmap[i] = (gray<<16)|(gray<<8)|gray;
                    gray += grayIncr;
                }

                colorModel = new IndexColorModel(8, 256, cmap, 0, false, -1,
                                                 DataBuffer.TYPE_BYTE);
                raster = Raster.createInterleavedRaster(DataBuffer.TYPE_BYTE,
                                                      width, height, 1, null);
            }
        break;

        case TYPE_USHORT_565_RGB:
            {
                colorModel = new DirectColorModel(16,
                                                  DCM_565_RED_MASK,
                                                  DCM_565_GRN_MASK,
                                                  DCM_565_BLU_MASK
                                                  );
                raster = colorModel.createCompatibleWritableRaster(width,
                                                                   height);
            }
            break;

        case TYPE_USHORT_555_RGB:
            {
                colorModel = new DirectColorModel(15,
                                                  DCM_555_RED_MASK,
                                                  DCM_555_GRN_MASK,
                                                  DCM_555_BLU_MASK
                                                  );
                raster = colorModel.createCompatibleWritableRaster(width,
                                                                   height);
            }
            break;

        default:
            throw new IllegalArgumentException ("Unknown image type " +
                                                imageType);
        }

        this.imageType = imageType;
    }

    /**
     * Constructs a <code>BufferedImage</code> of one of the predefined
     * image types:
     * TYPE_BYTE_BINARY or TYPE_BYTE_INDEXED.
     *
     * <p> If the image type is TYPE_BYTE_BINARY, the number of
     * entries in the color model is used to determine whether the
     * image should have 1, 2, or 4 bits per pixel.  If the color model
     * has 1 or 2 entries, the image will have 1 bit per pixel.  If it
     * has 3 or 4 entries, the image with have 2 bits per pixel.  If
     * it has between 5 and 16 entries, the image will have 4 bits per
     * pixel.  Otherwise, an IllegalArgumentException will be thrown.
     *
     * @param width     width of the created image
     * @param height    height of the created image
     * @param imageType type of the created image
     * @param cm        <code>IndexColorModel</code> of the created image
     * @throws IllegalArgumentException   if the imageType is not
     * TYPE_BYTE_BINARY or TYPE_BYTE_INDEXED or if the imageType is
     * TYPE_BYTE_BINARY and the color map has more than 16 entries.
     * @see #TYPE_BYTE_BINARY
     * @see #TYPE_BYTE_INDEXED
     */
    public BufferedImage (int width, 
                          int height,
                          int imageType,
                          IndexColorModel cm) {
        if (cm.hasAlpha() && cm.isAlphaPremultiplied()) {
            throw new IllegalArgumentException("This image types do not have "+
                                               "premultiplied alpha.");
        }

        switch(imageType) {
        case TYPE_BYTE_BINARY:
            int bits; // Will be set below
            int mapSize = cm.getMapSize();
            if (mapSize <= 2) {
                bits = 1;
            } else if (mapSize <= 4) {
                bits = 2;
            } else if (mapSize <= 16) {
                bits = 4;
            } else {
                throw new IllegalArgumentException
                    ("Color map for TYPE_BYTE_BINARY " +
                     "must have no more than 16 entries");
            }
            raster = Raster.createPackedRaster(DataBuffer.TYPE_BYTE,
                                                width, height, 1, bits, null);
            break;
            
        case TYPE_BYTE_INDEXED:
            raster = Raster.createInterleavedRaster(DataBuffer.TYPE_BYTE,
                                                    width, height, 1, null);
            break;
        default:
            throw new IllegalArgumentException("Invalid image type (" +
                                               imageType+").  Image type must"+
                                               " be either TYPE_BYTE_BINARY or "+
                                               " TYPE_BYTE_INDEXED");
        }

        if (!cm.isCompatibleRaster(raster)) {
            throw new IllegalArgumentException("Incompatible image type and IndexColorModel");
        }

        colorModel = cm;
        this.imageType = imageType;
    }

    /**
     * Constructs a new <code>BufferedImage</code> with a specified 
     * <code>ColorModel</code> and <code>Raster</code>.  If the number and
     * types of bands in the <code>SampleModel</code> of the 
     * <code>Raster</code> do not match the number and types required by
     * the <code>ColorModel</code> to represent its color and alpha
     * components, a {@link RasterFormatException} is thrown.  This
     * method can multiply or divide the color <code>Raster</code> data by
     * alpha to match the <code>alphaPremultiplied</code> state
     * in the <code>ColorModel</code>.  Properties for this 
     * <code>BufferedImage</code> can be established by passing
     * in a {@link Hashtable} of <code>String</code>/<code>Object</code> 
     * pairs.
     * @param cm <code>ColorModel</code> for the new image
     * @param raster     <code>Raster</code> for the image data
     * @param isRasterPremultiplied   if <code>true</code>, the data in
     *                  the raster has been premultiplied with alpha.
     * @param properties <code>Hashtable</code> of
     *                  <code>String</code>/<code>Object</code> pairs. 
     * @exception <code>RasterFormatException</code> if the number and
     * types of bands in the <code>SampleModel</code> of the
     * <code>Raster</code> do not match the number and types required by
     * the <code>ColorModel</code> to represent its color and alpha
     * components.
     * @exception <code>IllegalArgumentException</code> if 
     *		<code>raster</code> is incompatible with <code>cm</code>
     * @see ColorModel
     * @see Raster
     * @see WritableRaster
     */


/*
 *
 *  FOR NOW THE CODE WHICH DEFINES THE RASTER TYPE IS DUPLICATED BY DVF
 *  SEE THE METHOD DEFINERASTERTYPE @ RASTEROUTPUTMANAGER
 *
 */
    public BufferedImage (ColorModel cm,
                          WritableRaster raster,
                          boolean isRasterPremultiplied,
                          Hashtable properties) {

        if (!cm.isCompatibleRaster(raster)) {
            throw new
                IllegalArgumentException("Raster "+raster+
                                         " is incompatible with ColorModel "+
                                         cm);
        }

	if ((raster.minX != 0) || (raster.minY != 0)) {
            throw new
                IllegalArgumentException("Raster "+raster+
                                         " has minX or minY not equal to zero: "
                                         + raster.minX + " " + raster.minY);
	}

        colorModel = cm;
        this.raster  = raster;
        this.properties = properties;
        int numBands = raster.getNumBands();
        boolean isAlphaPre = cm.isAlphaPremultiplied();
        ColorSpace cs;
        
        // Force the raster data alpha state to match the premultiplied 
        // state in the color model
        coerceData(isRasterPremultiplied);

        SampleModel sm = raster.getSampleModel();
        cs = cm.getColorSpace();
        int csType = cs.getType();
        if (csType != ColorSpace.TYPE_RGB) {
            if (csType == ColorSpace.TYPE_GRAY
                && cm instanceof ComponentColorModel) {
                // Check if this might be a child raster (fix for bug 4240596)
                if (sm instanceof ComponentSampleModel &&
                    ((ComponentSampleModel)sm).getPixelStride() != numBands) {
                    imageType = TYPE_CUSTOM;
                } else if (raster instanceof ByteComponentRaster &&
                       raster.getNumBands() == 1 &&
                       cm.getComponentSize(0) == 8 &&
                       ((ByteComponentRaster)raster).getPixelStride() == 1) {
                    imageType = TYPE_BYTE_GRAY;
                } else if (raster instanceof ShortComponentRaster &&
                       raster.getNumBands() == 1 &&
                       cm.getComponentSize(0) == 16 &&
                       ((ShortComponentRaster)raster).getPixelStride() == 1) {
                    imageType = TYPE_USHORT_GRAY;
                }
            } else {
                imageType = TYPE_CUSTOM;
            }
            return;
        }

        if ((raster instanceof IntegerComponentRaster) &&
            (numBands == 3 || numBands == 4)) {
            IntegerComponentRaster iraster =
                (IntegerComponentRaster) raster;
            // Check if the raster params and the color model
            // are correct
            int pixSize = cm.getPixelSize();
            if (iraster.getPixelStride() == 1 &&
                cm instanceof DirectColorModel  &&
                (pixSize == 32 || pixSize == 24))
            {
                // Now check on the DirectColorModel params
                DirectColorModel dcm = (DirectColorModel) cm;
                int rmask = dcm.getRedMask();
                int gmask = dcm.getGreenMask();
                int bmask = dcm.getBlueMask();
                if (rmask == DCM_RED_MASK && gmask == DCM_GREEN_MASK &&
                    bmask == DCM_BLUE_MASK)
                {
                    if (dcm.getAlphaMask() == DCM_ALPHA_MASK) {
                        imageType = (isAlphaPre
                                     ? TYPE_INT_ARGB_PRE
                                     : TYPE_INT_ARGB);
                    }
                    else {
                        // No Alpha
                        if (!dcm.hasAlpha()) {
                            imageType = TYPE_INT_RGB;
                        }
                    } 
                }   // if (dcm.getRedMask() == DCM_RED_MASK &&
                else if (rmask == DCM_BGR_RED_MASK && gmask == DCM_BGR_GRN_MASK
                         && bmask == DCM_BGR_BLU_MASK) {
                    if (!dcm.hasAlpha()) {
                        imageType = TYPE_INT_BGR;
                    }
                }  // if (rmask == DCM_BGR_RED_MASK &&
            }   // if (iraster.getPixelStride() == 1 
        }   // ((raster instanceof IntegerComponentRaster) &&
        else if ((cm instanceof IndexColorModel) && (numBands == 1) &&
                 (!cm.hasAlpha() || !isAlphaPre))
        {
            IndexColorModel icm = (IndexColorModel) cm;
            int pixSize = icm.getPixelSize();

            if (raster instanceof BytePackedRaster) {
                imageType = TYPE_BYTE_BINARY;
            }   // if (raster instanceof BytePackedRaster)
            else if (raster instanceof ByteComponentRaster) {
                ByteComponentRaster braster = (ByteComponentRaster) raster;
                if (braster.getPixelStride() == 1 && pixSize <= 8) {
                    imageType = TYPE_BYTE_INDEXED;
                }   
            }
        }   // else if (cm instanceof IndexColorModel) && (numBands == 1))
        else if ((raster instanceof ShortComponentRaster)
                 && (cm instanceof DirectColorModel)
                 && (numBands == 3)
                 && !cm.hasAlpha())
        {
            DirectColorModel dcm = (DirectColorModel) cm;
            if (dcm.getRedMask() == DCM_565_RED_MASK) {
                if (dcm.getGreenMask() == DCM_565_GRN_MASK &&
                    dcm.getBlueMask()  == DCM_565_BLU_MASK) {
                    imageType = TYPE_USHORT_565_RGB;
                }
            }
            else if (dcm.getRedMask() == DCM_555_RED_MASK) {
                if (dcm.getGreenMask() == DCM_555_GRN_MASK &&
                    dcm.getBlueMask() == DCM_555_BLU_MASK) {
                    imageType = TYPE_USHORT_555_RGB;
                }
            }
        }   // else if ((cm instanceof IndexColorModel) && (numBands == 1))
        else if ((raster instanceof ByteComponentRaster) 
                 && (cm instanceof ComponentColorModel)
                 && (raster.getSampleModel() instanceof PixelInterleavedSampleModel)
                 && (numBands == 3 || numBands == 4))
        {
            ComponentColorModel ccm = (ComponentColorModel) cm;
            PixelInterleavedSampleModel csm =
                (PixelInterleavedSampleModel)raster.getSampleModel();
            ByteComponentRaster braster = (ByteComponentRaster) raster;
            int[] offs = csm.getBandOffsets();
            if (ccm.getNumComponents() != numBands) {
                throw new RasterFormatException("Number of components in "+
                                                "ColorModel ("+
                                                ccm.getNumComponents()+
                                                ") does not match # in "+
                                                " Raster ("+numBands+")");
            }
            int[] nBits = ccm.getComponentSize();
            boolean is8bit = true;
            for (int i=0; i < numBands; i++) {
                if (nBits[i] != 8) {
                    is8bit = false;
                    break;
                }
            }
            if (is8bit &&
                offs[0] == numBands-1 &&
                offs[1] == numBands-2 &&
                offs[2] == numBands-3)
            {
                if (numBands == 3) {
                    imageType = TYPE_3BYTE_BGR;
                }
                else if (offs[3] == 0) {
                    imageType = (isAlphaPre
                                 ? TYPE_4BYTE_ABGR_PRE
                                 : TYPE_4BYTE_ABGR);
                }
            }
        }   // else if ((raster instanceof ByteComponentRaster) &&
    }

    /**
     * Returns the image type.  If it is not one of the known types,
     * TYPE_CUSTOM is returned.
     * @return the image type of this <code>BufferedImage</code>.
     * @see #TYPE_INT_RGB
     * @see #TYPE_INT_ARGB
     * @see #TYPE_INT_ARGB_PRE
     * @see #TYPE_INT_BGR
     * @see #TYPE_3BYTE_BGR
     * @see #TYPE_4BYTE_ABGR
     * @see #TYPE_4BYTE_ABGR_PRE
     * @see #TYPE_BYTE_GRAY
     * @see #TYPE_BYTE_BINARY
     * @see #TYPE_BYTE_INDEXED
     * @see #TYPE_USHORT_GRAY
     * @see #TYPE_USHORT_565_RGB
     * @see #TYPE_USHORT_555_RGB
     * @see #TYPE_CUSTOM
     */
    public int getType() {
        return imageType;
    }
    
    /**
     * Returns the <code>ColorModel</code>.
     * @return the <code>ColorModel</code> of this
     *  <code>BufferedImage</code>.
     */
    public ColorModel getColorModel() {