FileDocCategorySizeDatePackage
IndexColorModel.javaAPI DocJava SE 5 API56821Fri Aug 26 14:56:54 BST 2005java.awt.image

IndexColorModel

public class IndexColorModel extends ColorModel
The IndexColorModel class is a ColorModel class that works with pixel values consisting of a single sample that is an index into a fixed colormap in the default sRGB color space. The colormap specifies red, green, blue, and optional alpha components corresponding to each index. All components are represented in the colormap as 8-bit unsigned integral values. Some constructors allow the caller to specify "holes" in the colormap by indicating which colormap entries are valid and which represent unusable colors via the bits set in a BigInteger object. This color model is similar to an X11 PseudoColor visual.

Some constructors provide a means to specify an alpha component for each pixel in the colormap, while others either provide no such means or, in some cases, a flag to indicate whether the colormap data contains alpha values. If no alpha is supplied to the constructor, an opaque alpha component (alpha = 1.0) is assumed for each entry. An optional transparent pixel value can be supplied that indicates a pixel to be made completely transparent, regardless of any alpha component supplied or assumed for that pixel value. Note that the color components in the colormap of an IndexColorModel objects are never pre-multiplied with the alpha components.

The transparency of an IndexColorModel object is determined by examining the alpha components of the colors in the colormap and choosing the most specific value after considering the optional alpha values and any transparent index specified. The transparency value is Transparency.OPAQUE only if all valid colors in the colormap are opaque and there is no valid transparent pixel. If all valid colors in the colormap are either completely opaque (alpha = 1.0) or completely transparent (alpha = 0.0), which typically occurs when a valid transparent pixel is specified, the value is Transparency.BITMASK. Otherwise, the value is Transparency.TRANSLUCENT, indicating that some valid color has an alpha component that is neither completely transparent nor completely opaque (0.0 < alpha < 1.0).

If an IndexColorModel object has a transparency value of Transparency.OPAQUE, then the hasAlpha and getNumComponents methods (both inherited from ColorModel) return false and 3, respectively. For any other transparency value, hasAlpha returns true and getNumComponents returns 4.

The index represented by a pixel value is stored in the least significant n bits of the pixel representations passed to the methods of this class, where n is the pixel size specified to the constructor for a particular IndexColorModel object; n must be between 1 and 16, inclusive. Higher order bits in pixel representations are assumed to be zero. For those methods that use a primitive array pixel representation of type transferType, the array length is always one. The transfer types supported are DataBuffer.TYPE_BYTE and DataBuffer.TYPE_USHORT. A single int pixel representation is valid for all objects of this class, since it is always possible to represent pixel values used with this class in a single int. Therefore, methods that use this representation do not throw an IllegalArgumentException due to an invalid pixel value.

Many of the methods in this class are final. The reason for this is that the underlying native graphics code makes assumptions about the layout and operation of this class and those assumptions are reflected in the implementations of the methods here that are marked final. You can subclass this class for other reasons, but you cannot override or modify the behaviour of those methods.

see
ColorModel
see
ColorSpace
see
DataBuffer
version
10 Feb 1997

Fields Summary
private int[]
rgb
private int
map_size
private int
transparent_index
private boolean
allgrayopaque
private BigInteger
validBits
private static int[]
opaqueBits
private static int[]
alphaBits
private static final int
CACHESIZE
private int[]
lookupcache
Constructors Summary
public IndexColorModel(int bits, int size, byte[] r, byte[] g, byte[] b)
Constructs an IndexColorModel from the specified arrays of red, green, and blue components. Pixels described by this color model all have alpha components of 255 unnormalized (1.0 normalized), which means they are fully opaque. All of the arrays specifying the color components must have at least the specified number of entries. The ColorSpace is the default sRGB space. Since there is no alpha information in any of the arguments to this constructor, the transparency value is always Transparency.OPAQUE. The transfer type is the smallest of DataBuffer.TYPE_BYTE or DataBuffer.TYPE_USHORT that can hold a single pixel.

param
bits the number of bits each pixel occupies
param
size the size of the color component arrays
param
r the array of red color components
param
g the array of green color components
param
b the array of blue color components
throws
IllegalArgumentException if bits is less than 1 or greater than 16
throws
IllegalArgumentException if size is less than 1


        
     
        ColorModel.loadLibraries();
        initIDs();
    
	super(bits, opaqueBits,
              ColorSpace.getInstance(ColorSpace.CS_sRGB),
              false, false, OPAQUE,
              ColorModel.getDefaultTransferType(bits));
        if (bits < 1 || bits > 16) {
            throw new IllegalArgumentException("Number of bits must be between"
                                               +" 1 and 16.");
        }
	setRGBs(size, r, g, b, null);
    
public IndexColorModel(int bits, int size, byte[] r, byte[] g, byte[] b, int trans)
Constructs an IndexColorModel from the given arrays of red, green, and blue components. Pixels described by this color model all have alpha components of 255 unnormalized (1.0 normalized), which means they are fully opaque, except for the indicated pixel to be made transparent. All of the arrays specifying the color components must have at least the specified number of entries. The ColorSpace is the default sRGB space. The transparency value may be Transparency.OPAQUE or Transparency.BITMASK depending on the arguments, as specified in the class description above. The transfer type is the smallest of DataBuffer.TYPE_BYTE or DataBuffer.TYPE_USHORT that can hold a single pixel.

param
bits the number of bits each pixel occupies
param
size the size of the color component arrays
param
r the array of red color components
param
g the array of green color components
param
b the array of blue color components
param
trans the index of the transparent pixel
throws
IllegalArgumentException if bits is less than 1 or greater than 16
throws
IllegalArgumentException if size is less than 1

	super(bits, opaqueBits,
              ColorSpace.getInstance(ColorSpace.CS_sRGB),
              false, false, OPAQUE,
              ColorModel.getDefaultTransferType(bits));
        if (bits < 1 || bits > 16) {
            throw new IllegalArgumentException("Number of bits must be between"
                                               +" 1 and 16.");
        }
	setRGBs(size, r, g, b, null);
	setTransparentPixel(trans);
    
public IndexColorModel(int bits, int size, byte[] r, byte[] g, byte[] b, byte[] a)
Constructs an IndexColorModel from the given arrays of red, green, blue and alpha components. All of the arrays specifying the components must have at least the specified number of entries. The ColorSpace is the default sRGB space. The transparency value may be any of Transparency.OPAQUE, Transparency.BITMASK, or Transparency.TRANSLUCENT depending on the arguments, as specified in the class description above. The transfer type is the smallest of DataBuffer.TYPE_BYTE or DataBuffer.TYPE_USHORT that can hold a single pixel.

param
bits the number of bits each pixel occupies
param
size the size of the color component arrays
param
r the array of red color components
param
g the array of green color components
param
b the array of blue color components
param
a the array of alpha value components
throws
IllegalArgumentException if bits is less than 1 or greater than 16
throws
IllegalArgumentException if size is less than 1

        super (bits, alphaBits,
               ColorSpace.getInstance(ColorSpace.CS_sRGB),
               true, false, TRANSLUCENT,
               ColorModel.getDefaultTransferType(bits));
        if (bits < 1 || bits > 16) {
            throw new IllegalArgumentException("Number of bits must be between"
                                               +" 1 and 16.");
        }
        setRGBs (size, r, g, b, a);
    
public IndexColorModel(int bits, int size, byte[] cmap, int start, boolean hasalpha)
Constructs an IndexColorModel from a single array of interleaved red, green, blue and optional alpha components. The array must have enough values in it to fill all of the needed component arrays of the specified size. The ColorSpace is the default sRGB space. The transparency value may be any of Transparency.OPAQUE, Transparency.BITMASK, or Transparency.TRANSLUCENT depending on the arguments, as specified in the class description above. The transfer type is the smallest of DataBuffer.TYPE_BYTE or DataBuffer.TYPE_USHORT that can hold a single pixel.

param
bits the number of bits each pixel occupies
param
size the size of the color component arrays
param
cmap the array of color components
param
start the starting offset of the first color component
param
hasalpha indicates whether alpha values are contained in the cmap array
throws
IllegalArgumentException if bits is less than 1 or greater than 16
throws
IllegalArgumentException if size is less than 1

	this(bits, size, cmap, start, hasalpha, -1);
        if (bits < 1 || bits > 16) {
            throw new IllegalArgumentException("Number of bits must be between"
                                               +" 1 and 16.");
        }
    
public IndexColorModel(int bits, int size, byte[] cmap, int start, boolean hasalpha, int trans)
Constructs an IndexColorModel from a single array of interleaved red, green, blue and optional alpha components. The specified transparent index represents a pixel that is made entirely transparent regardless of any alpha value specified for it. The array must have enough values in it to fill all of the needed component arrays of the specified size. The ColorSpace is the default sRGB space. The transparency value may be any of Transparency.OPAQUE, Transparency.BITMASK, or Transparency.TRANSLUCENT depending on the arguments, as specified in the class description above. The transfer type is the smallest of DataBuffer.TYPE_BYTE or DataBuffer.TYPE_USHORT that can hold a single pixel.

param
bits the number of bits each pixel occupies
param
size the size of the color component arrays
param
cmap the array of color components
param
start the starting offset of the first color component
param
hasalpha indicates whether alpha values are contained in the cmap array
param
trans the index of the fully transparent pixel
throws
IllegalArgumentException if bits is less than 1 or greater than 16
throws
IllegalArgumentException if size is less than 1

	// REMIND: This assumes the ordering: RGB[A]
	super(bits, opaqueBits,
              ColorSpace.getInstance(ColorSpace.CS_sRGB),
              false, false, OPAQUE,
              ColorModel.getDefaultTransferType(bits));

        if (bits < 1 || bits > 16) {
            throw new IllegalArgumentException("Number of bits must be between"
                                               +" 1 and 16.");
        }
        if (size < 1) {
            throw new IllegalArgumentException("Map size ("+size+
                                               ") must be >= 1");
        }
	map_size = size;
	rgb = new int[calcRealMapSize(bits, size)];
	int j = start;
	int alpha = 0xff;
	boolean allgray = true;
        int transparency = OPAQUE;
	for (int i = 0; i < size; i++) {
	    int r = cmap[j++] & 0xff;
	    int g = cmap[j++] & 0xff;
	    int b = cmap[j++] & 0xff;
	    allgray = allgray && (r == g) && (g == b);
	    if (hasalpha) {
		alpha = cmap[j++] & 0xff;
		if (alpha != 0xff) {
		    if (alpha == 0x00) {
			if (transparency == OPAQUE) {
			    transparency = BITMASK;
			}
			if (transparent_index < 0) {
			    transparent_index = i;
			}
		    } else {
			transparency = TRANSLUCENT;
		    }
		    allgray = false;
		}
	    }
	    rgb[i] = (alpha << 24) | (r << 16) | (g << 8) | b;
	}
	this.allgrayopaque = allgray;
	setTransparency(transparency);
	setTransparentPixel(trans);
    
public IndexColorModel(int bits, int size, int[] cmap, int start, boolean hasalpha, int trans, int transferType)
Constructs an IndexColorModel from an array of ints where each int is comprised of red, green, blue, and optional alpha components in the default RGB color model format. The specified transparent index represents a pixel that is made entirely transparent regardless of any alpha value specified for it. The array must have enough values in it to fill all of the needed component arrays of the specified size. The ColorSpace is the default sRGB space. The transparency value may be any of Transparency.OPAQUE, Transparency.BITMASK, or Transparency.TRANSLUCENT depending on the arguments, as specified in the class description above.

param
bits the number of bits each pixel occupies
param
size the size of the color component arrays
param
cmap the array of color components
param
start the starting offset of the first color component
param
hasalpha indicates whether alpha values are contained in the cmap array
param
trans the index of the fully transparent pixel
param
transferType the data type of the array used to represent pixel values. The data type must be either DataBuffer.TYPE_BYTE or DataBuffer.TYPE_USHORT.
throws
IllegalArgumentException if bits is less than 1 or greater than 16
throws
IllegalArgumentException if size is less than 1
throws
IllegalArgumentException if transferType is not one of DataBuffer.TYPE_BYTE or DataBuffer.TYPE_USHORT

	// REMIND: This assumes the ordering: RGB[A]
	super(bits, opaqueBits,
              ColorSpace.getInstance(ColorSpace.CS_sRGB),
              false, false, OPAQUE,
              transferType);

        if (bits < 1 || bits > 16) {
            throw new IllegalArgumentException("Number of bits must be between"
                                               +" 1 and 16.");
        }
        if (size < 1) {
            throw new IllegalArgumentException("Map size ("+size+
                                               ") must be >= 1");
        }
        if ((transferType != DataBuffer.TYPE_BYTE) &&
            (transferType != DataBuffer.TYPE_USHORT)) {
            throw new IllegalArgumentException("transferType must be either" +
                "DataBuffer.TYPE_BYTE or DataBuffer.TYPE_USHORT");
        }

	setRGBs(size, cmap, start, hasalpha);
        setTransparentPixel(trans);
    
public IndexColorModel(int bits, int size, int[] cmap, int start, int transferType, BigInteger validBits)
Constructs an IndexColorModel from an int array where each int is comprised of red, green, blue, and alpha components in the default RGB color model format. The array must have enough values in it to fill all of the needed component arrays of the specified size. The ColorSpace is the default sRGB space. The transparency value may be any of Transparency.OPAQUE, Transparency.BITMASK, or Transparency.TRANSLUCENT depending on the arguments, as specified in the class description above. The transfer type must be one of DataBuffer.TYPE_BYTE DataBuffer.TYPE_USHORT. The BigInteger object specifies the valid/invalid pixels in the cmap array. A pixel is valid if the BigInteger value at that index is set, and is invalid if the BigInteger bit at that index is not set.

param
bits the number of bits each pixel occupies
param
size the size of the color component array
param
cmap the array of color components
param
start the starting offset of the first color component
param
transferType the specified data type
param
validBits a BigInteger object. If a bit is set in the BigInteger, the pixel at that index is valid. If a bit is not set, the pixel at that index is considered invalid. If null, all pixels are valid. Only bits from 0 to the map size are considered.
throws
IllegalArgumentException if bits is less than 1 or greater than 16
throws
IllegalArgumentException if size is less than 1
throws
IllegalArgumentException if transferType is not one of DataBuffer.TYPE_BYTE or DataBuffer.TYPE_USHORT

        super (bits, alphaBits,
               ColorSpace.getInstance(ColorSpace.CS_sRGB),
               true, false, TRANSLUCENT,
               transferType);
        
        if (bits < 1 || bits > 16) {
            throw new IllegalArgumentException("Number of bits must be between"
                                               +" 1 and 16.");
        }
        if (size < 1) {
            throw new IllegalArgumentException("Map size ("+size+
                                               ") must be >= 1");
        }
        if ((transferType != DataBuffer.TYPE_BYTE) &&
            (transferType != DataBuffer.TYPE_USHORT)) {
            throw new IllegalArgumentException("transferType must be either" +
                "DataBuffer.TYPE_BYTE or DataBuffer.TYPE_USHORT");
        }

        if (validBits != null) {
            // Check to see if it is all valid
            for (int i=0; i < size; i++) {
                if (!validBits.testBit(i)) {
                    this.validBits = validBits;
                    break;
                }
            }
        }
        
	setRGBs(size, cmap, start, true);
    
Methods Summary
private intcalcRealMapSize(int bits, int size)

	int newSize = Math.max(1 << bits, size);
	return Math.max(newSize, 256);
    
public java.awt.image.BufferedImageconvertToIntDiscrete(java.awt.image.Raster raster, boolean forceARGB)
Returns a new BufferedImage of TYPE_INT_ARGB or TYPE_INT_RGB that has a Raster with pixel data computed by expanding the indices in the source Raster using the color/alpha component arrays of this ColorModel. If forceARGB is true, a TYPE_INT_ARGB image is returned regardless of whether or not this ColorModel has an alpha component array or a transparent pixel.

param
raster the specified Raster
param
forceARGB if true, the returned BufferedImage is TYPE_INT_ARGB; otherwise it is TYPE_INT_RGB
return
a BufferedImage created with the specified Raster
throws
IllegalArgumentException if the raster argument is not compatible with this IndexColorModel

        ColorModel cm;

        if (!isCompatibleRaster(raster)) {
            throw new IllegalArgumentException("This raster is not compatible" +
                 "with this IndexColorModel.");
        }
        if (forceARGB || transparency == TRANSLUCENT) {
            cm = ColorModel.getRGBdefault();
        }
        else if (transparency == BITMASK) {
            cm = new DirectColorModel(25, 0xff0000, 0x00ff00, 0x0000ff,
                                      0x1000000);
        }
        else {
            cm = new DirectColorModel(24, 0xff0000, 0x00ff00, 0x0000ff);
        }

        int w = raster.getWidth();
        int h = raster.getHeight();
        WritableRaster discreteRaster = 
                  cm.createCompatibleWritableRaster(w, h);
        Object obj = null;
        int[] data = null;

        int rX = raster.getMinX();
        int rY = raster.getMinY();

        for (int y=0; y < h; y++, rY++) {
            obj = raster.getDataElements(rX, rY, w, 1, obj);
            if (obj instanceof int[]) {
                data = (int[])obj;
            } else {
                data = DataBuffer.toIntArray(obj);
            }
            for (int x=0; x < w; x++) {
                data[x] = rgb[data[x]];
            }
            discreteRaster.setDataElements(0, y, w, 1, data);
        }
        
        return new BufferedImage(cm, discreteRaster, false, null);
    
public java.awt.image.SampleModelcreateCompatibleSampleModel(int w, int h)
Creates a SampleModel with the specified width and height that has a data layout compatible with this ColorModel.

param
w the width to apply to the new SampleModel
param
h the height to apply to the new SampleModel
return
a SampleModel object with the specified width and height.
throws
IllegalArgumentException if w or h is not greater than 0
see
SampleModel

        int[] off = new int[1];
        off[0] = 0;
        if (pixel_bits == 1 || pixel_bits == 2 || pixel_bits == 4) {
            return new MultiPixelPackedSampleModel(transferType, w, h,
                                                   pixel_bits);
        }
        else {
            return new ComponentSampleModel(transferType, w, h, 1, w,
                                            off);
        }
    
public java.awt.image.WritableRastercreateCompatibleWritableRaster(int w, int h)
Creates a WritableRaster with the specified width and height that has a data layout (SampleModel) compatible with this ColorModel. This method only works for color models with 16 or fewer bits per pixel.

Since IndexColorModel can be subclassed, any subclass that supports greater than 16 bits per pixel must override this method.

param
w the width to apply to the new WritableRaster
param
h the height to apply to the new WritableRaster
return
a WritableRaster object with the specified width and height.
throws
UnsupportedOperationException if the number of bits in a pixel is greater than 16
see
WritableRaster
see
SampleModel

        WritableRaster raster;

        if (pixel_bits == 1 || pixel_bits == 2 || pixel_bits == 4) {
            // TYPE_BINARY
            raster = Raster.createPackedRaster(DataBuffer.TYPE_BYTE,
                                               w, h, 1, pixel_bits, null);
        }
        else if (pixel_bits <= 8) {
            raster = Raster.createInterleavedRaster(DataBuffer.TYPE_BYTE,
                                                  w,h,1,null);
        }
        else if (pixel_bits <= 16) {
            raster = Raster.createInterleavedRaster(DataBuffer.TYPE_USHORT,
                                                  w,h,1,null);
        }
        else {
            throw new
                UnsupportedOperationException("This method is not supported "+
                                              " for pixel bits > 16.");
        }
        return raster;
    
public voidfinalize()
Disposes of system resources associated with this ColorModel once this ColorModel is no longer referenced.

	sun.awt.image.BufImgSurfaceData.freeNativeICMData(this);
    
private java.math.BigIntegergetAllValid()

	int numbytes = (map_size+7)/8;
	byte[] valid = new byte[numbytes];
	java.util.Arrays.fill(valid, (byte)0xff);
	valid[0] = (byte)(0xff >>> (numbytes*8 - map_size));

	return new BigInteger(1, valid);
    
public final intgetAlpha(int pixel)
Returns the alpha component for the specified pixel, scaled from 0 to 255. The pixel value is specified as an int.

param
pixel the specified pixel
return
the value of the alpha component for the specified pixel

	return (rgb[pixel] >> 24) & 0xff;
    
public final voidgetAlphas(byte[] a)
Copies the array of alpha transparency components into the specified array. Only the initial entries of the array as specified by getMapSize are written.

param
a the specified array into which the elements of the array of alpha components are copied

        for (int i = 0; i < map_size; i++) {
            a[i] = (byte) (rgb[i] >> 24);
        }
    
public final intgetBlue(int pixel)
Returns the blue color component for the specified pixel, scaled from 0 to 255 in the default RGB ColorSpace, sRGB. The pixel value is specified as an int. The returned value is a non pre-multiplied value.

param
pixel the specified pixel
return
the value of the blue color component for the specified pixel

	return rgb[pixel] & 0xff;
    
public final voidgetBlues(byte[] b)
Copies the array of blue color components into the specified array. Only the initial entries of the array as specified by getMapSize are written.

param
b the specified array into which the elements of the array of blue color components are copied

        for (int i = 0; i < map_size; i++) {
            b[i] = (byte) rgb[i];
        }
    
public int[]getComponentSize()
Returns an array of the number of bits for each color/alpha component. The array contains the color components in the order red, green, blue, followed by the alpha component, if present.

return
an array containing the number of bits of each color and alpha component of this IndexColorModel

        if (nBits == null) {
            if (supportsAlpha) {
                nBits = new int[4];
                nBits[3] = 8;
            }
            else {
                nBits = new int[3];
            }
            nBits[0] = nBits[1] = nBits[2] = 8;
        }
        return nBits;
    
public int[]getComponents(int pixel, int[] components, int offset)
Returns an array of unnormalized color/alpha components for a specified pixel in this ColorModel. The pixel value is specified as an int. If the components array is null, a new array is allocated that contains offset + getNumComponents() elements. The components array is returned, with the alpha component included only if hasAlpha returns true. Color/alpha components are stored in the components array starting at offset even if the array is allocated by this method. An ArrayIndexOutOfBoundsException is thrown if the components array is not null and is not large enough to hold all the color and alpha components starting at offset.

param
pixel the specified pixel
param
components the array to receive the color and alpha components of the specified pixel
param
offset the offset into the components array at which to start storing the color and alpha components
return
an array containing the color and alpha components of the specified pixel starting at the specified offset.
see
ColorModel#hasAlpha
see
ColorModel#getNumComponents

        if (components == null) {
            components = new int[offset+numComponents];
        }

        // REMIND: Needs to change if different color space
        components[offset+0] = getRed(pixel);
        components[offset+1] = getGreen(pixel);
        components[offset+2] = getBlue(pixel);
        if (supportsAlpha && (components.length-offset) > 3) {
            components[offset+3] = getAlpha(pixel);
        }
        
        return components;
    
public int[]getComponents(java.lang.Object pixel, int[] components, int offset)
Returns an array of unnormalized color/alpha components for a specified pixel in this ColorModel. The pixel value is specified by an array of data elements of type transferType passed in as an object reference. If pixel is not a primitive array of type transferType, a ClassCastException is thrown. An ArrayIndexOutOfBoundsException is thrown if pixel is not large enough to hold a pixel value for this ColorModel. If the components array is null, a new array is allocated that contains offset + getNumComponents() elements. The components array is returned, with the alpha component included only if hasAlpha returns true. Color/alpha components are stored in the components array starting at offset even if the array is allocated by this method. An ArrayIndexOutOfBoundsException is also thrown if the components array is not null and is not large enough to hold all the color and alpha components starting at offset.

Since IndexColorModel can be subclassed, subclasses inherit the implementation of this method and if they don't override it then they throw an exception if they use an unsupported transferType.

param
pixel the specified pixel
param
components an array that receives the color and alpha components of the specified pixel
param
offset the index into the components array at which to begin storing the color and alpha components of the specified pixel
return
an array containing the color and alpha components of the specified pixel starting at the specified offset.
throws
ArrayIndexOutOfBoundsException if pixel is not large enough to hold a pixel value for this ColorModel or if the components array is not null and is not large enough to hold all the color and alpha components starting at offset
throws
ClassCastException if pixel is not a primitive array of type transferType
throws
UnsupportedOperationException if transferType is not one of the supported transer types
see
ColorModel#hasAlpha
see
ColorModel#getNumComponents

        int intpixel;
        switch (transferType) {
            case DataBuffer.TYPE_BYTE:
               byte bdata[] = (byte[])pixel;
               intpixel = bdata[0] & 0xff;
            break;
            case DataBuffer.TYPE_USHORT:
               short sdata[] = (short[])pixel;
               intpixel = sdata[0] & 0xffff;
            break;
            case DataBuffer.TYPE_INT:
               int idata[] = (int[])pixel;
               intpixel = idata[0];
            break;
            default:
               throw new UnsupportedOperationException("This method has not been "+
                   "implemented for transferType " + transferType);
        }
        return getComponents(intpixel, components, offset);
    
public intgetDataElement(int[] components, int offset)
Returns a pixel value represented as an int in this ColorModel given an array of unnormalized color/alpha components. An ArrayIndexOutOfBoundsException is thrown if the components array is not large enough to hold all of the color and alpha components starting at offset. Since ColorModel can be subclassed, subclasses inherit the implementation of this method and if they don't override it then they throw an exception if they use an unsupported transferType.

param
components an array of unnormalized color and alpha components
param
offset the index into components at which to begin retrieving the color and alpha components
return
an int pixel value in this ColorModel corresponding to the specified components.
throws
ArrayIndexOutOfBoundsException if the components array is not large enough to hold all of the color and alpha components starting at offset
throws
UnsupportedOperationException if transferType is invalid

        int rgb = (components[offset+0]<<16)
            | (components[offset+1]<<8) | (components[offset+2]);
        if (supportsAlpha) {
            rgb |= (components[offset+3]<<24);
        }
        else {
            rgb |= 0xff000000;
        }
        Object inData = getDataElements(rgb, null);
        int pixel;
        switch (transferType) {
            case DataBuffer.TYPE_BYTE:
               byte bdata[] = (byte[])inData;
               pixel = bdata[0] & 0xff;
            break;
            case DataBuffer.TYPE_USHORT:
               short sdata[] = (short[])inData;
               pixel = sdata[0];
            break;
            case DataBuffer.TYPE_INT:
               int idata[] = (int[])inData;
               pixel = idata[0];
            break;
            default:
               throw new UnsupportedOperationException("This method has not been "+
                   "implemented for transferType " + transferType);
        }
        return pixel;
    
public synchronized java.lang.ObjectgetDataElements(int rgb, java.lang.Object pixel)
Returns a data element array representation of a pixel in this ColorModel, given an integer pixel representation in the default RGB color model. This array can then be passed to the {@link WritableRaster#setDataElements(int, int, java.lang.Object) setDataElements} method of a {@link WritableRaster} object. If the pixel variable is null, a new array is allocated. If pixel is not null, it must be a primitive array of type transferType; otherwise, a ClassCastException is thrown. An ArrayIndexOutOfBoundsException is thrown if pixel is not large enough to hold a pixel value for this ColorModel. The pixel array is returned.

Since IndexColorModel can be subclassed, subclasses inherit the implementation of this method and if they don't override it then they throw an exception if they use an unsupported transferType.

param
rgb the integer pixel representation in the default RGB color model
param
pixel the specified pixel
return
an array representation of the specified pixel in this IndexColorModel.
throws
ClassCastException if pixel is not a primitive array of type transferType
throws
ArrayIndexOutOfBoundsException if pixel is not large enough to hold a pixel value for this ColorModel
throws
UnsupportedOperationException if transferType is invalid
see
WritableRaster#setDataElements
see
SampleModel#setDataElements


                                                                                                                                                                                                                                
           
        int red = (rgb>>16) & 0xff;
        int green = (rgb>>8) & 0xff;
        int blue  = rgb & 0xff;
        int alpha = (rgb>>>24);
        int pix = 0;

	for (int i = CACHESIZE - 2; i >= 0; i -= 2) {
	    if ((pix = lookupcache[i]) == 0) {
		break;
	    }
	    if (rgb == lookupcache[i+1]) {
		return installpixel(pixel, ~pix);
	    }
	}

	if (allgrayopaque) {
	    int minDist = 256;
	    int d;
	    int gray = (int) (red*77 + green*150 + blue*29 + 128)/256;

	    for (int i = 0; i < map_size; i++) {
		if (this.rgb[i] == 0x0) {
		    // For allgrayopaque colormaps, entries are 0
		    // iff they are an invalid color and should be
		    // ignored during color searches.
		    continue;
		}
		d = (this.rgb[i] & 0xff) - gray;
		if (d < 0) d = -d;
		if (d < minDist) {
		    pix = i;
		    if (d == 0) {
			break;
		    }
		    minDist = d;
		}
	    }
	} else if (alpha == 0) {
            // Return transparent pixel if we have one
            if (transparent_index >= 0) {
                pix = transparent_index;
            }
            else {
                // Search for smallest alpha
		int smallestAlpha = 256;
                for (int i = 0; i < map_size; i++) {
		    int a = this.rgb[i] >>> 24;
		    if (smallestAlpha > alpha &&
			(validBits == null || validBits.testBit(i)))
		    {
			smallestAlpha = alpha;
			pix = i;
                    }
                }
            }
        } else {
            // a heuristic which says find the closest color,
            // after finding the closest alpha
            // if user wants different behavior, they can derive
            // a class and override this method
            // SLOW --- but accurate
            // REMIND - need a native implementation, and inverse color-map
            int smallestError = 255 * 255 * 255;   // largest possible
	    int smallestAlphaError = 255;

	    if (false && red == green && green == blue) {
		// Grayscale
	    }

            for (int i=0; i < map_size; i++) {
		int lutrgb = this.rgb[i];
		if (lutrgb == rgb) {
		    pix = i;
		    break;
		}
                int tmp = (lutrgb>>>24) - alpha;
		if (tmp < 0) {
		    tmp = -tmp;
		}
		if (tmp <= smallestAlphaError) {
		    smallestAlphaError = tmp;
		    tmp = ((lutrgb>>16) & 0xff) - red;
		    int currentError = tmp * tmp;
		    if (currentError < smallestError) {
			tmp = ((lutrgb>>8) & 0xff) - green;
			currentError += tmp * tmp;
			if (currentError < smallestError) {
			    tmp = (lutrgb & 0xff) - blue;
			    currentError += tmp * tmp;
			    if (currentError < smallestError &&
				(validBits == null || validBits.testBit(i)))
			    {
				pix = i;
				smallestError = currentError;
			    }
			}
		    }
		}
            }
        }
	System.arraycopy(lookupcache, 2, lookupcache, 0, CACHESIZE - 2);
	lookupcache[CACHESIZE - 1] = rgb;
	lookupcache[CACHESIZE - 2] = ~pix;
	return installpixel(pixel, pix);
    
public java.lang.ObjectgetDataElements(int[] components, int offset, java.lang.Object pixel)
Returns a data element array representation of a pixel in this ColorModel given an array of unnormalized color/alpha components. This array can then be passed to the setDataElements method of a WritableRaster object. An ArrayIndexOutOfBoundsException is thrown if the components array is not large enough to hold all of the color and alpha components starting at offset. If the pixel variable is null, a new array is allocated. If pixel is not null, it must be a primitive array of type transferType; otherwise, a ClassCastException is thrown. An ArrayIndexOutOfBoundsException is thrown if pixel is not large enough to hold a pixel value for this ColorModel.

Since IndexColorModel can be subclassed, subclasses inherit the implementation of this method and if they don't override it then they throw an exception if they use an unsupported transferType

param
components an array of unnormalized color and alpha components
param
offset the index into components at which to begin retrieving color and alpha components
param
pixel the Object representing an array of color and alpha components
return
an Object representing an array of color and alpha components.
throws
ClassCastException if pixel is not a primitive array of type transferType
throws
ArrayIndexOutOfBoundsException if pixel is not large enough to hold a pixel value for this ColorModel or the components array is not large enough to hold all of the color and alpha components starting at offset
throws
UnsupportedOperationException if transferType is not one of the supported transer types
see
WritableRaster#setDataElements
see
SampleModel#setDataElements

        int rgb = (components[offset+0]<<16) | (components[offset+1]<<8)
            | (components[offset+2]);
        if (supportsAlpha) {
            rgb |= (components[offset+3]<<24);
        }
        else {
            rgb &= 0xff000000;
        }
        return getDataElements(rgb, pixel);
    
public final intgetGreen(int pixel)
Returns the green color component for the specified pixel, scaled from 0 to 255 in the default RGB ColorSpace, sRGB. The pixel value is specified as an int. The returned value is a non pre-multiplied value.

param
pixel the specified pixel
return
the value of the green color component for the specified pixel

	return (rgb[pixel] >> 8) & 0xff;
    
public final voidgetGreens(byte[] g)
Copies the array of green color components into the specified array. Only the initial entries of the array as specified by getMapSize are written.

param
g the specified array into which the elements of the array of green color components are copied

	for (int i = 0; i < map_size; i++) {
	    g[i] = (byte) (rgb[i] >> 8);
	}
    
public final intgetMapSize()
Returns the size of the color/alpha component arrays in this IndexColorModel.

return
the size of the color and alpha component arrays.

        return map_size;
    
public final intgetRGB(int pixel)
Returns the color/alpha components of the pixel in the default RGB color model format. The pixel value is specified as an int. The returned value is in a non pre-multiplied format.

param
pixel the specified pixel
return
the color and alpha components of the specified pixel
see
ColorModel#getRGBdefault

	return rgb[pixel];
    
public final voidgetRGBs(int[] rgb)
Converts data for each index from the color and alpha component arrays to an int in the default RGB ColorModel format and copies the resulting 32-bit ARGB values into the specified array. Only the initial entries of the array as specified by getMapSize are written.

param
rgb the specified array into which the converted ARGB values from this array of color and alpha components are copied.

        System.arraycopy(this.rgb, 0, rgb, 0, map_size);
    
public final intgetRed(int pixel)
Returns the red color component for the specified pixel, scaled from 0 to 255 in the default RGB ColorSpace, sRGB. The pixel value is specified as an int. The returned value is a non pre-multiplied value.

param
pixel the specified pixel
return
the value of the red color component for the specified pixel

	return (rgb[pixel] >> 16) & 0xff;
    
public final voidgetReds(byte[] r)
Copies the array of red color components into the specified array. Only the initial entries of the array as specified by {@link #getMapSize() getMapSize} are written.

param
r the specified array into which the elements of the array of red color components are copied

	for (int i = 0; i < map_size; i++) {
	    r[i] = (byte) (rgb[i] >> 16);
	}
    
public intgetTransparency()
Returns the transparency. Returns either OPAQUE, BITMASK, or TRANSLUCENT

return
the transparency of this IndexColorModel
see
Transparency#OPAQUE
see
Transparency#BITMASK
see
Transparency#TRANSLUCENT

        return transparency;
    
public final intgetTransparentPixel()
Returns the index of a transparent pixel in this IndexColorModel or -1 if there is no pixel with an alpha value of 0. If a transparent pixel was explicitly specified in one of the constructors by its index, then that index will be preferred, otherwise, the index of any pixel which happens to be fully transparent may be returned.

return
the index of a transparent pixel in this IndexColorModel object, or -1 if there is no such pixel

	return transparent_index;
    
public java.math.BigIntegergetValidPixels()
Returns a BigInteger that indicates the valid/invalid pixels in the colormap. A bit is valid if the BigInteger value at that index is set, and is invalid if the BigInteger value at that index is not set. The only valid ranges to query in the BigInteger are between 0 and the map size.

return
a BigInteger indicating the valid/invalid pixels.

        if (validBits == null) {
            return getAllValid();
        }
        else {
            return validBits;
        }
    
private static native voidinitIDs()

private java.lang.Objectinstallpixel(java.lang.Object pixel, int pix)

        switch (transferType) {
        case DataBuffer.TYPE_INT:
	    int[] intObj;
	    if (pixel == null) {
		pixel = intObj = new int[1];
	    } else {
		intObj = (int[]) pixel;
	    }
	    intObj[0] = pix;
            break;
        case DataBuffer.TYPE_BYTE:
	    byte[] byteObj;
	    if (pixel == null) {
		pixel = byteObj = new byte[1];
	    } else {
		byteObj = (byte[]) pixel;
	    }
	    byteObj[0] = (byte) pix;
            break;
        case DataBuffer.TYPE_USHORT:
	    short[] shortObj;
	    if (pixel == null) {
		pixel = shortObj = new short[1];
	    } else {
		shortObj = (short[]) pixel;
	    }
	    shortObj[0] = (short) pix;
            break;
        default:
            throw new UnsupportedOperationException("This method has not been "+
                             "implemented for transferType " + transferType);
        }
        return pixel;
    
public booleanisCompatibleRaster(java.awt.image.Raster raster)
Returns true if raster is compatible with this ColorModel or false if it is not compatible with this ColorModel.

param
raster the {@link Raster} object to test for compatibility
return
true if raster is compatible with this ColorModel; false otherwise.


	int size = raster.getSampleModel().getSampleSize(0);
        return ((raster.getTransferType() == transferType) &&
		(raster.getNumBands() == 1) && ((1 << size) >= map_size));
    
public booleanisCompatibleSampleModel(java.awt.image.SampleModel sm)
Checks if the specified SampleModel is compatible with this ColorModel. If sm is null, this method returns false.

param
sm the specified SampleModel, or null
return
true if the specified SampleModel is compatible with this ColorModel; false otherwise.
see
SampleModel

        // fix 4238629
        if (! (sm instanceof ComponentSampleModel) &&
            ! (sm instanceof MultiPixelPackedSampleModel)   ) {
            return false;
        }

        // Transfer type must be the same
        if (sm.getTransferType() != transferType) {
            return false;
        }

        if (sm.getNumBands() != 1) {
            return false;
        }
        
        return true;
    
public booleanisValid(int pixel)
Returns whether or not the pixel is valid.

param
pixel the specified pixel value
return
true if pixel is valid; false otherwise.

	return ((pixel >= 0 && pixel < map_size) &&
		(validBits == null || validBits.testBit(pixel)));
    
public booleanisValid()
Returns whether or not all of the pixels are valid.

return
true if all pixels are valid; false otherwise.

        return (validBits == null);
    
private voidsetRGBs(int size, int[] cmap, int start, boolean hasalpha)

	map_size = size;
	rgb = new int[calcRealMapSize(pixel_bits, size)];
	int j = start;
        int transparency = OPAQUE;
	boolean allgray = true;
	BigInteger validBits = this.validBits;
	for (int i = 0; i < size; i++, j++) {
	    if (validBits != null && !validBits.testBit(i)) {
		continue;
	    }
	    int cmaprgb = cmap[j];
	    int r = (cmaprgb >> 16) & 0xff;
	    int g = (cmaprgb >>  8) & 0xff;
	    int b = (cmaprgb      ) & 0xff;
	    allgray = allgray && (r == g) && (g == b);
	    if (hasalpha) {
		int alpha = cmaprgb >>> 24;
		if (alpha != 0xff) {
		    if (alpha == 0x00) {
			if (transparency == OPAQUE) {
			    transparency = BITMASK;
			}
			if (transparent_index < 0) {
			    transparent_index = i;
			}
		    } else {
			transparency = TRANSLUCENT;
		    }
		    allgray = false;
		}
	    } else {
		cmaprgb |= 0xff000000;
	    }
	    rgb[i] = cmaprgb;
	}
	this.allgrayopaque = allgray;
	setTransparency(transparency);
    
private voidsetRGBs(int size, byte[] r, byte[] g, byte[] b, byte[] a)

        if (size < 1) {
            throw new IllegalArgumentException("Map size ("+size+
                                               ") must be >= 1");
        }
	map_size = size;
	rgb = new int[calcRealMapSize(pixel_bits, size)];
	int alpha = 0xff;
        int transparency = OPAQUE;
	boolean allgray = true;
	for (int i = 0; i < size; i++) {
	    int rc = r[i] & 0xff;
	    int gc = g[i] & 0xff;
	    int bc = b[i] & 0xff;
	    allgray = allgray && (rc == gc) && (gc == bc);
	    if (a != null) {
		alpha = a[i] & 0xff;
		if (alpha != 0xff) {
		    if (alpha == 0x00) {
			if (transparency == OPAQUE) {
			    transparency = BITMASK;
			}
			if (transparent_index < 0) {
			    transparent_index = i;
			}
		    } else {
			transparency = TRANSLUCENT;
		    }
		    allgray = false;
		}
	    }
	    rgb[i] = (alpha << 24) | (rc << 16) | (gc << 8) | bc;
	}
	this.allgrayopaque = allgray;
	setTransparency(transparency);
    
private voidsetTransparency(int transparency)

	if (this.transparency != transparency) {
	    this.transparency = transparency;
	    if (transparency == OPAQUE) {
		supportsAlpha = false;
		numComponents = 3;
		nBits = opaqueBits;
	    } else {
		supportsAlpha = true;
		numComponents = 4;
		nBits = alphaBits;
	    }
	}
    
private voidsetTransparentPixel(int trans)

	if (trans >= 0 && trans < map_size) {
	    rgb[trans] &= 0x00ffffff;
	    transparent_index = trans;
	    allgrayopaque = false;
	    if (this.transparency == OPAQUE) {
		setTransparency(BITMASK);
	    }
	}
    
public java.lang.StringtoString()
Returns the String representation of the contents of this ColorModelobject.

return
a String representing the contents of this ColorModel object.

       return new String("IndexColorModel: #pixelBits = "+pixel_bits
                         + " numComponents = "+numComponents
                         + " color space = "+colorSpace
                         + " transparency = "+transparency
                         + " transIndex   = "+transparent_index
                         + " has alpha = "+supportsAlpha
                         + " isAlphaPre = "+isAlphaPremultiplied
                         );