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.
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.
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.
ColorModel
, ColorSpace
, DataBuffer
pixel_bits, transferType
BITMASK, OPAQUE, TRANSLUCENT
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.
bits
- the number of bits each pixel occupiessize
- the size of the color component arraysr
- the array of red color componentsg
- the array of green color componentsb
- the array of blue color componentsIllegalArgumentException
- if bits
is less than 1 or greater than 16IllegalArgumentException
- if size
is less than 1public 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.
bits
- the number of bits each pixel occupiessize
- the size of the color component arraysr
- the array of red color componentsg
- the array of green color componentsb
- the array of blue color componentstrans
- the index of the transparent pixelIllegalArgumentException
- if bits
is less than 1 or greater than 16IllegalArgumentException
- if size
is less than 1public 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.
bits
- the number of bits each pixel occupiessize
- the size of the color component arraysr
- the array of red color componentsg
- the array of green color componentsb
- the array of blue color componentsa
- the array of alpha value componentsIllegalArgumentException
- if bits
is less than 1 or greater than 16IllegalArgumentException
- if size
is less than 1public 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.
bits
- the number of bits each pixel occupiessize
- the size of the color component arrayscmap
- the array of color componentsstart
- the starting offset of the first color componenthasalpha
- indicates whether alpha values are contained in the cmap
arrayIllegalArgumentException
- if bits
is less than 1 or greater than 16IllegalArgumentException
- if size
is less than 1public 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.
bits
- the number of bits each pixel occupiessize
- the size of the color component arrayscmap
- the array of color componentsstart
- the starting offset of the first color componenthasalpha
- indicates whether alpha values are contained in the cmap
arraytrans
- the index of the fully transparent pixelIllegalArgumentException
- if bits
is less than 1 or greater than 16IllegalArgumentException
- if size
is less than 1public 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.
bits
- the number of bits each pixel occupiessize
- the size of the color component arrayscmap
- the array of color componentsstart
- the starting offset of the first color componenthasalpha
- indicates whether alpha values are contained in the cmap
arraytrans
- the index of the fully transparent pixeltransferType
- the data type of the array used to represent pixel values. The data type must be either DataBuffer.TYPE_BYTE
or DataBuffer.TYPE_USHORT
.IllegalArgumentException
- if bits
is less than 1 or greater than 16IllegalArgumentException
- if size
is less than 1IllegalArgumentException
- if transferType
is not one of DataBuffer.TYPE_BYTE
or DataBuffer.TYPE_USHORT
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.
bits
- the number of bits each pixel occupiessize
- the size of the color component arraycmap
- the array of color componentsstart
- the starting offset of the first color componenttransferType
- the specified data typevalidBits
- 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.IllegalArgumentException
- if bits
is less than 1 or greater than 16IllegalArgumentException
- if size
is less than 1IllegalArgumentException
- if transferType
is not one of DataBuffer.TYPE_BYTE
or DataBuffer.TYPE_USHORT
public int getTransparency()
Returns the transparency. Returns either OPAQUE, BITMASK, or TRANSLUCENT
getTransparency
in interface Transparency
getTransparency
in class ColorModel
IndexColorModel
Transparency.OPAQUE
, Transparency.BITMASK
, Transparency.TRANSLUCENT
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.
getComponentSize
in class ColorModel
IndexColorModel
public final int getMapSize()
Returns the size of the color/alpha component arrays in this IndexColorModel
.
public final int getTransparentPixel()
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.
IndexColorModel
object, or -1 if there is no such pixelpublic final void getReds(byte[] r)
Copies the array of red color components into the specified array. Only the initial entries of the array as specified by getMapSize
are written.
r
- the specified array into which the elements of the array of red color components are copiedpublic final void getGreens(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.
g
- the specified array into which the elements of the array of green color components are copiedpublic final void getBlues(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.
b
- the specified array into which the elements of the array of blue color components are copiedpublic final void getAlphas(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.
a
- the specified array into which the elements of the array of alpha components are copiedpublic final void getRGBs(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.
rgb
- the specified array into which the converted ARGB values from this array of color and alpha components are copied.public final int getRed(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. Only the lower n bits of the pixel value, as specified in the class description above, are used to calculate the returned value. The returned value is a non pre-multiplied value.
getRed
in class ColorModel
pixel
- the specified pixelpublic final int getGreen(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. Only the lower n bits of the pixel value, as specified in the class description above, are used to calculate the returned value. The returned value is a non pre-multiplied value.
getGreen
in class ColorModel
pixel
- the specified pixelpublic final int getBlue(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. Only the lower n bits of the pixel value, as specified in the class description above, are used to calculate the returned value. The returned value is a non pre-multiplied value.
getBlue
in class ColorModel
pixel
- the specified pixelpublic final int getAlpha(int pixel)
Returns the alpha component for the specified pixel, scaled from 0 to 255. The pixel value is specified as an int. Only the lower n bits of the pixel value, as specified in the class description above, are used to calculate the returned value.
getAlpha
in class ColorModel
pixel
- the specified pixelpublic final int getRGB(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. Only the lower n bits of the pixel value, as specified in the class description above, are used to calculate the returned value. The returned value is in a non pre-multiplied format.
getRGB
in class ColorModel
pixel
- the specified pixelColorModel.getRGBdefault()
public Object getDataElements(int rgb, 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 setDataElements
method of a 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
.
getDataElements
in class ColorModel
rgb
- the integer pixel representation in the default RGB color modelpixel
- the specified pixelIndexColorModel
.ClassCastException
- if pixel
is not a primitive array of type transferType
ArrayIndexOutOfBoundsException
- if pixel
is not large enough to hold a pixel value for this ColorModel
UnsupportedOperationException
- if transferType
is invalidWritableRaster.setDataElements(int, int, java.lang.Object)
, SampleModel.setDataElements(int, int, java.lang.Object, java.awt.image.DataBuffer)
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
.
getComponents
in class ColorModel
pixel
- the specified pixelcomponents
- the array to receive the color and alpha components of the specified pixeloffset
- the offset into the components
array at which to start storing the color and alpha componentsColorModel.hasAlpha()
, ColorModel.getNumComponents()
public int[] getComponents(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
.
getComponents
in class ColorModel
pixel
- the specified pixelcomponents
- an array that receives the color and alpha components of the specified pixeloffset
- the index into the components
array at which to begin storing the color and alpha components of the specified pixelArrayIndexOutOfBoundsException
- 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
ClassCastException
- if pixel
is not a primitive array of type transferType
UnsupportedOperationException
- if transferType
is not one of the supported transfer typesColorModel.hasAlpha()
, ColorModel.getNumComponents()
public int getDataElement(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.
getDataElement
in class ColorModel
components
- an array of unnormalized color and alpha componentsoffset
- the index into components
at which to begin retrieving the color and alpha componentsint
pixel value in this ColorModel
corresponding to the specified components.ArrayIndexOutOfBoundsException
- if the components
array is not large enough to hold all of the color and alpha components starting at offset
UnsupportedOperationException
- if transferType
is invalidpublic Object getDataElements(int[] components, int offset, 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
getDataElements
in class ColorModel
components
- an array of unnormalized color and alpha componentsoffset
- the index into components
at which to begin retrieving color and alpha componentspixel
- the Object
representing an array of color and alpha componentsObject
representing an array of color and alpha components.ClassCastException
- if pixel
is not a primitive array of type transferType
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
UnsupportedOperationException
- if transferType
is not one of the supported transfer typesWritableRaster.setDataElements(int, int, java.lang.Object)
, SampleModel.setDataElements(int, int, java.lang.Object, java.awt.image.DataBuffer)
public WritableRaster createCompatibleWritableRaster(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.
createCompatibleWritableRaster
in class ColorModel
w
- the width to apply to the new WritableRaster
h
- the height to apply to the new WritableRaster
WritableRaster
object with the specified width and height.UnsupportedOperationException
- if the number of bits in a pixel is greater than 16WritableRaster
, SampleModel
public boolean isCompatibleRaster(Raster raster)
Returns true
if raster
is compatible with this ColorModel
or false
if it is not compatible with this ColorModel
.
isCompatibleRaster
in class ColorModel
raster
- the Raster
object to test for compatibilitytrue
if raster
is compatible with this ColorModel
; false
otherwise.public SampleModel createCompatibleSampleModel(int w, int h)
Creates a SampleModel
with the specified width and height that has a data layout compatible with this ColorModel
.
createCompatibleSampleModel
in class ColorModel
w
- the width to apply to the new SampleModel
h
- the height to apply to the new SampleModel
SampleModel
object with the specified width and height.IllegalArgumentException
- if w
or h
is not greater than 0SampleModel
public boolean isCompatibleSampleModel(SampleModel sm)
Checks if the specified SampleModel
is compatible with this ColorModel
. If sm
is null
, this method returns false
.
isCompatibleSampleModel
in class ColorModel
sm
- the specified SampleModel
, or null
true
if the specified SampleModel
is compatible with this ColorModel
; false
otherwise.SampleModel
public BufferedImage convertToIntDiscrete(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
. Only the lower n bits of each index value in the source Raster
, as specified in the class description above, are used to compute the color/alpha values in the returned image. 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.
raster
- the specified Raster
forceARGB
- if true
, the returned BufferedImage
is TYPE_INT_ARGB; otherwise it is TYPE_INT_RGBBufferedImage
created with the specified Raster
IllegalArgumentException
- if the raster argument is not compatible with this IndexColorModelpublic boolean isValid(int pixel)
Returns whether or not the pixel is valid.
pixel
- the specified pixel valuetrue
if pixel
is valid; false
otherwise.public boolean isValid()
Returns whether or not all of the pixels are valid.
true
if all pixels are valid; false
otherwise.public BigInteger getValidPixels()
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.
BigInteger
indicating the valid/invalid pixels.public void finalize()
Disposes of system resources associated with this ColorModel
once this ColorModel
is no longer referenced.
finalize
in class ColorModel
WeakReference
, PhantomReference
public String toString()
Returns the String
representation of the contents of this ColorModel
object.
toString
in class ColorModel
String
representing the contents of this ColorModel
object.
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Documentation extracted from Debian's OpenJDK Development Kit package.
Licensed under the GNU General Public License, version 2, with the Classpath Exception.
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