Transparency
ComponentColorModel
, IndexColorModel
, PackedColorModel
public abstract class ColorModel extends Object implements Transparency
ColorModel
abstract class encapsulates the methods for translating a pixel value to color components (for example, red, green, and blue) and an alpha component. In order to render an image to the screen, a printer, or another image, pixel values must be converted to color and alpha components. As arguments to or return values from methods of this class, pixels are represented as 32-bit ints or as arrays of primitive types. The number, order, and interpretation of color components for a ColorModel
is specified by its ColorSpace
. A ColorModel
used with pixel data that does not include alpha information treats all pixels as opaque, which is an alpha value of 1.0. This ColorModel
class supports two representations of pixel values. A pixel value can be a single 32-bit int or an array of primitive types. The Java(tm) Platform 1.0 and 1.1 APIs represented pixels as single byte
or single int
values. For purposes of the ColorModel
class, pixel value arguments were passed as ints. The Java(tm) 2 Platform API introduced additional classes for representing images. With BufferedImage
or RenderedImage
objects, based on Raster
and SampleModel
classes, pixel values might not be conveniently representable as a single int. Consequently, ColorModel
now has methods that accept pixel values represented as arrays of primitive types. The primitive type used by a particular ColorModel
object is called its transfer type.
ColorModel
objects used with images for which pixel values are not conveniently representable as a single int throw an IllegalArgumentException
when methods taking a single int pixel argument are called. Subclasses of ColorModel
must specify the conditions under which this occurs. This does not occur with DirectColorModel
or IndexColorModel
objects.
Currently, the transfer types supported by the Java 2D(tm) API are DataBuffer.TYPE_BYTE, DataBuffer.TYPE_USHORT, DataBuffer.TYPE_INT, DataBuffer.TYPE_SHORT, DataBuffer.TYPE_FLOAT, and DataBuffer.TYPE_DOUBLE. Most rendering operations will perform much faster when using ColorModels and images based on the first three of these types. In addition, some image filtering operations are not supported for ColorModels and images based on the latter three types. The transfer type for a particular ColorModel
object is specified when the object is created, either explicitly or by default. All subclasses of ColorModel
must specify what the possible transfer types are and how the number of elements in the primitive arrays representing pixels is determined.
For BufferedImages
, the transfer type of its Raster
and of the Raster
object's SampleModel
(available from the getTransferType
methods of these classes) must match that of the ColorModel
. The number of elements in an array representing a pixel for the Raster
and SampleModel
(available from the getNumDataElements
methods of these classes) must match that of the ColorModel
.
The algorithm used to convert from pixel values to color and alpha components varies by subclass. For example, there is not necessarily a one-to-one correspondence between samples obtained from the SampleModel
of a BufferedImage
object's Raster
and color/alpha components. Even when there is such a correspondence, the number of bits in a sample is not necessarily the same as the number of bits in the corresponding color/alpha component. Each subclass must specify how the translation from pixel values to color/alpha components is done.
Methods in the ColorModel
class use two different representations of color and alpha components - a normalized form and an unnormalized form. In the normalized form, each component is a float
value between some minimum and maximum values. For the alpha component, the minimum is 0.0 and the maximum is 1.0. For color components the minimum and maximum values for each component can be obtained from the ColorSpace
object. These values will often be 0.0 and 1.0 (e.g. normalized component values for the default sRGB color space range from 0.0 to 1.0), but some color spaces have component values with different upper and lower limits. These limits can be obtained using the getMinValue
and getMaxValue
methods of the ColorSpace
class. Normalized color component values are not premultiplied. All ColorModels
must support the normalized form.
In the unnormalized form, each component is an unsigned integral value between 0 and 2n - 1, where n is the number of significant bits for a particular component. If pixel values for a particular ColorModel
represent color samples premultiplied by the alpha sample, unnormalized color component values are also premultiplied. The unnormalized form is used only with instances of ColorModel
whose ColorSpace
has minimum component values of 0.0 for all components and maximum values of 1.0 for all components. The unnormalized form for color and alpha components can be a convenient representation for ColorModels
whose normalized component values all lie between 0.0 and 1.0. In such cases the integral value 0 maps to 0.0 and the value 2n - 1 maps to 1.0. In other cases, such as when the normalized component values can be either negative or positive, the unnormalized form is not convenient. Such ColorModel
objects throw an IllegalArgumentException
when methods involving an unnormalized argument are called. Subclasses of ColorModel
must specify the conditions under which this occurs.
Modifier and Type | Field | Description |
---|---|---|
protected int |
pixel_bits |
The total number of bits in the pixel. |
protected int |
transferType |
Data type of the array used to represent pixel values. |
BITMASK, OPAQUE, TRANSLUCENT
Modifier | Constructor | Description |
---|---|---|
Constructs a ColorModel that translates pixels of the specified number of bits to color/alpha components. |
||
protected |
Constructs a ColorModel that translates pixel values to color/alpha components. |
Modifier and Type | Method | Description |
---|---|---|
ColorModel |
coerceData |
Forces the raster data to match the state specified in the isAlphaPremultiplied variable, assuming the data is currently correctly described by this ColorModel . |
SampleModel |
createCompatibleSampleModel |
Creates a SampleModel with the specified width and height that has a data layout compatible with this ColorModel . |
WritableRaster |
createCompatibleWritableRaster |
Creates a WritableRaster with the specified width and height that has a data layout (SampleModel ) compatible with this ColorModel . |
boolean |
equals |
This method simply delegates to the default implementation in Object which is identical to an == test since this class cannot enforce the issues of a proper equality test among multiple independent subclass branches. |
abstract int |
getAlpha |
Returns the alpha component for the specified pixel, scaled from 0 to 255. |
int |
getAlpha |
Returns the alpha component for the specified pixel, scaled from 0 to 255. |
WritableRaster |
getAlphaRaster |
Returns a Raster representing the alpha channel of an image, extracted from the input Raster , provided that pixel values of this ColorModel represent color and alpha information as separate spatial bands (e.g. |
abstract int |
getBlue |
Returns the blue color component for the specified pixel, scaled from 0 to 255 in the default RGB ColorSpace, sRGB. |
int |
getBlue |
Returns the blue color component for the specified pixel, scaled from 0 to 255 in the default RGB ColorSpace , sRGB. |
final ColorSpace |
getColorSpace() |
Returns the ColorSpace associated with this ColorModel . |
int[] |
getComponents |
Returns an array of unnormalized color/alpha components given a pixel in this ColorModel . |
int[] |
getComponents |
Returns an array of unnormalized color/alpha components given a pixel in this ColorModel . |
int[] |
getComponentSize() |
Returns an array of the number of bits per color/alpha component. |
int |
getComponentSize |
Returns the number of bits for the specified color/alpha component. |
int |
getDataElement |
Returns a pixel value represented as an int in this ColorModel , given an array of normalized color/alpha components. |
int |
getDataElement |
Returns a pixel value represented as an int in this ColorModel , given an array of unnormalized color/alpha components. |
Object |
getDataElements |
Returns a data element array representation of a pixel in this ColorModel , given an array of normalized color/alpha components. |
Object |
getDataElements |
Returns a data element array representation of a pixel in this ColorModel , given an array of unnormalized color/alpha components. |
Object |
getDataElements |
Returns a data element array representation of a pixel in this ColorModel , given an integer pixel representation in the default RGB color model. |
abstract int |
getGreen |
Returns the green color component for the specified pixel, scaled from 0 to 255 in the default RGB ColorSpace, sRGB. |
int |
getGreen |
Returns the green color component for the specified pixel, scaled from 0 to 255 in the default RGB ColorSpace , sRGB. |
float[] |
getNormalizedComponents |
Returns an array of all of the color/alpha components in normalized form, given an unnormalized component array. |
float[] |
getNormalizedComponents |
Returns an array of all of the color/alpha components in normalized form, given a pixel in this ColorModel . |
int |
getNumColorComponents() |
Returns the number of color components in this ColorModel . |
int |
getNumComponents() |
Returns the number of components, including alpha, in this ColorModel . |
int |
getPixelSize() |
Returns the number of bits per pixel described by this ColorModel . |
abstract int |
getRed |
Returns the red color component for the specified pixel, scaled from 0 to 255 in the default RGB ColorSpace, sRGB. |
int |
getRed |
Returns the red color component for the specified pixel, scaled from 0 to 255 in the default RGB ColorSpace , sRGB. |
int |
getRGB |
Returns the color/alpha components of the pixel in the default RGB color model format. |
int |
getRGB |
Returns the color/alpha components for the specified pixel in the default RGB color model format. |
static ColorModel |
getRGBdefault() |
Returns a DirectColorModel that describes the default format for integer RGB values used in many of the methods in the AWT image interfaces for the convenience of the programmer. |
final int |
getTransferType() |
Returns the transfer type of this ColorModel . |
int |
getTransparency() |
Returns the transparency. |
int[] |
getUnnormalizedComponents |
Returns an array of all of the color/alpha components in unnormalized form, given a normalized component array. |
final boolean |
hasAlpha() |
Returns whether or not alpha is supported in this ColorModel . |
int |
hashCode() |
This method simply delegates to the default implementation in Object which returns the system ID for the class. |
final boolean |
isAlphaPremultiplied() |
Returns whether or not the alpha has been premultiplied in the pixel values to be translated by this ColorModel . |
boolean |
isCompatibleRaster |
Returns true if raster is compatible with this ColorModel and false if it is not. |
boolean |
isCompatibleSampleModel |
Checks if the SampleModel is compatible with this ColorModel . |
String |
toString() |
Returns the String representation of the contents of this ColorModel object. |
protected int pixel_bits
protected int transferType
public ColorModel(int bits)
ColorModel
that translates pixels of the specified number of bits to color/alpha components. The color space is the default RGB ColorSpace
, which is sRGB. Pixel values are assumed to include alpha information. If color and alpha information are represented in the pixel value as separate spatial bands, the color bands are assumed not to be premultiplied with the alpha value. The transparency type is java.awt.Transparency.TRANSLUCENT. The transfer type will be the smallest of DataBuffer.TYPE_BYTE, DataBuffer.TYPE_USHORT, or DataBuffer.TYPE_INT that can hold a single pixel (or DataBuffer.TYPE_UNDEFINED if bits is greater than 32). Since this constructor has no information about the number of bits per color and alpha component, any subclass calling this constructor should override any method that requires this information.bits
- the number of bits of a pixelIllegalArgumentException
- if the number of bits in bits
is less than 1protected ColorModel(int pixel_bits, int[] bits, ColorSpace cspace, boolean hasAlpha, boolean isAlphaPremultiplied, int transparency, int transferType)
ColorModel
that translates pixel values to color/alpha components. Color components will be in the specified ColorSpace
. pixel_bits
is the number of bits in the pixel values. The bits array specifies the number of significant bits per color and alpha component. Its length should be the number of components in the ColorSpace
if there is no alpha information in the pixel values, or one more than this number if there is alpha information. hasAlpha
indicates whether or not alpha information is present. The boolean
isAlphaPremultiplied
specifies how to interpret pixel values in which color and alpha information are represented as separate spatial bands. If the boolean
is true
, color samples are assumed to have been multiplied by the alpha sample. The transparency
specifies what alpha values can be represented by this color model. The transfer type is the type of primitive array used to represent pixel values. Note that the bits array contains the number of significant bits per color/alpha component after the translation from pixel values. For example, for an IndexColorModel
with pixel_bits
equal to 16, the bits array might have four elements with each element set to 8.pixel_bits
- the number of bits in the pixel valuesbits
- array that specifies the number of significant bits per color and alpha componentcspace
- the specified ColorSpace
hasAlpha
- true
if alpha information is present; false
otherwiseisAlphaPremultiplied
- true
if color samples are assumed to be premultiplied by the alpha samples; false
otherwisetransparency
- what alpha values can be represented by this color modeltransferType
- the type of the array used to represent pixel valuesIllegalArgumentException
- if the length of the bit array is less than the number of color or alpha components in this ColorModel
, or if the transparency is not a valid value.IllegalArgumentException
- if the sum of the number of bits in bits
is less than 1 or if any of the elements in bits
is less than 0.public static ColorModel getRGBdefault()
DirectColorModel
that describes the default format for integer RGB values used in many of the methods in the AWT image interfaces for the convenience of the programmer. The color space is the default ColorSpace
, sRGB. The format for the RGB values is an integer with 8 bits each of alpha, red, green, and blue color components ordered correspondingly from the most significant byte to the least significant byte, as in: 0xAARRGGBB. Color components are not premultiplied by the alpha component. This format does not necessarily represent the native or the most efficient ColorModel
for a particular device or for all images. It is merely used as a common color model format.DirectColorModel
object describing default RGB values.public final boolean hasAlpha()
ColorModel
.true
if alpha is supported in this ColorModel
; false
otherwise.public final boolean isAlphaPremultiplied()
ColorModel
. If the boolean is true
, this ColorModel
is to be used to interpret pixel values in which color and alpha information are represented as separate spatial bands, and color samples are assumed to have been multiplied by the alpha sample.true
if the alpha values are premultiplied in the pixel values to be translated by this ColorModel
; false
otherwise.public final int getTransferType()
ColorModel
. The transfer type is the type of primitive array used to represent pixel values as arrays.public int getPixelSize()
ColorModel
.public int getComponentSize(int componentIdx)
ColorSpace
. Typically, this order reflects the name of the color space type. For example, for TYPE_RGB, index 0 corresponds to red, index 1 to green, and index 2 to blue. If this ColorModel
supports alpha, the alpha component corresponds to the index following the last color component.componentIdx
- the index of the color/alpha componentArrayIndexOutOfBoundsException
- if componentIdx
is greater than or equal to the number of components or less than zeroNullPointerException
- if the number of bits array is null
public int[] getComponentSize()
ColorSpace
, followed by the alpha component, if present.public int getTransparency()
getTransparency
in interface Transparency
ColorModel
.public int getNumComponents()
ColorModel
. This is equal to the number of color components, optionally plus one, if there is an alpha component.ColorModel
public int getNumColorComponents()
ColorModel
. This is the number of components returned by ColorSpace.getNumComponents()
.ColorModel
.public abstract int getRed(int pixel)
IllegalArgumentException
is thrown if pixel values for this ColorModel
are not conveniently representable as a single int. The returned value is not a pre-multiplied value. For example, if the alpha is premultiplied, this method divides it out before returning the value. If the alpha value is 0, the red value is 0.pixel
- a specified pixelpublic abstract int getGreen(int pixel)
IllegalArgumentException
is thrown if pixel values for this ColorModel
are not conveniently representable as a single int. The returned value is a non pre-multiplied value. For example, if the alpha is premultiplied, this method divides it out before returning the value. If the alpha value is 0, the green value is 0.pixel
- the specified pixelpublic abstract int getBlue(int pixel)
IllegalArgumentException
is thrown if pixel values for this ColorModel
are not conveniently representable as a single int. The returned value is a non pre-multiplied value, for example, if the alpha is premultiplied, this method divides it out before returning the value. If the alpha value is 0, the blue value is 0.pixel
- the specified pixelpublic abstract int getAlpha(int pixel)
IllegalArgumentException
is thrown if pixel values for this ColorModel
are not conveniently representable as a single int.pixel
- the specified pixelpublic int getRGB(int pixel)
IllegalArgumentException
thrown if pixel values for this ColorModel
are not conveniently representable as a single int. The returned value is in a non pre-multiplied format. For example, if the alpha is premultiplied, this method divides it out of the color components. If the alpha value is 0, the color values are 0.pixel
- the specified pixelpublic int getRed(Object inData)
ColorSpace
, sRGB. A color conversion is done if necessary. The pixel value is specified by an array of data elements of type transferType passed in as an object reference. The returned value is a non pre-multiplied value. For example, if alpha is premultiplied, this method divides it out before returning the value. If the alpha value is 0, the red value is 0. If inData
is not a primitive array of type transferType, a ClassCastException
is thrown. An ArrayIndexOutOfBoundsException
is thrown if inData
is not large enough to hold a pixel value for this ColorModel
. If this transferType
is not supported, a UnsupportedOperationException
will be thrown. Since ColorModel
is an abstract class, any instance must be an instance of a subclass. Subclasses inherit the implementation of this method and if they don't override it, this method throws an exception if the subclass uses a transferType
other than DataBuffer.TYPE_BYTE
, DataBuffer.TYPE_USHORT
, or DataBuffer.TYPE_INT
.inData
- an array of pixel valuesClassCastException
- if inData
is not a primitive array of type transferType
ArrayIndexOutOfBoundsException
- if inData
is not large enough to hold a pixel value for this ColorModel
UnsupportedOperationException
- if this transferType
is not supported by this ColorModel
public int getGreen(Object inData)
ColorSpace
, sRGB. A color conversion is done if necessary. The pixel value is specified by an array of data elements of type transferType passed in as an object reference. The returned value will be a non pre-multiplied value. For example, if the alpha is premultiplied, this method divides it out before returning the value. If the alpha value is 0, the green value is 0. If inData
is not a primitive array of type transferType, a ClassCastException
is thrown. An ArrayIndexOutOfBoundsException
is thrown if inData
is not large enough to hold a pixel value for this ColorModel
. If this transferType
is not supported, a UnsupportedOperationException
will be thrown. Since ColorModel
is an abstract class, any instance must be an instance of a subclass. Subclasses inherit the implementation of this method and if they don't override it, this method throws an exception if the subclass uses a transferType
other than DataBuffer.TYPE_BYTE
, DataBuffer.TYPE_USHORT
, or DataBuffer.TYPE_INT
.inData
- an array of pixel valuesClassCastException
- if inData
is not a primitive array of type transferType
ArrayIndexOutOfBoundsException
- if inData
is not large enough to hold a pixel value for this ColorModel
UnsupportedOperationException
- if this transferType
is not supported by this ColorModel
public int getBlue(Object inData)
ColorSpace
, sRGB. A color conversion is done if necessary. The pixel value is specified by an array of data elements of type transferType passed in as an object reference. The returned value is a non pre-multiplied value. For example, if the alpha is premultiplied, this method divides it out before returning the value. If the alpha value is 0, the blue value will be 0. If inData
is not a primitive array of type transferType, a ClassCastException
is thrown. An ArrayIndexOutOfBoundsException
is thrown if inData
is not large enough to hold a pixel value for this ColorModel
. If this transferType
is not supported, a UnsupportedOperationException
will be thrown. Since ColorModel
is an abstract class, any instance must be an instance of a subclass. Subclasses inherit the implementation of this method and if they don't override it, this method throws an exception if the subclass uses a transferType
other than DataBuffer.TYPE_BYTE
, DataBuffer.TYPE_USHORT
, or DataBuffer.TYPE_INT
.inData
- an array of pixel valuesClassCastException
- if inData
is not a primitive array of type transferType
ArrayIndexOutOfBoundsException
- if inData
is not large enough to hold a pixel value for this ColorModel
UnsupportedOperationException
- if this transferType
is not supported by this ColorModel
public int getAlpha(Object inData)
ClassCastException
is thrown. An ArrayIndexOutOfBoundsException
is thrown if inData
is not large enough to hold a pixel value for this ColorModel
. If this transferType
is not supported, a UnsupportedOperationException
will be thrown. Since ColorModel
is an abstract class, any instance must be an instance of a subclass. Subclasses inherit the implementation of this method and if they don't override it, this method throws an exception if the subclass uses a transferType
other than DataBuffer.TYPE_BYTE
, DataBuffer.TYPE_USHORT
, or DataBuffer.TYPE_INT
.inData
- the specified pixelClassCastException
- if inData
is not a primitive array of type transferType
ArrayIndexOutOfBoundsException
- if inData
is not large enough to hold a pixel value for this ColorModel
UnsupportedOperationException
- if this tranferType
is not supported by this ColorModel
public int getRGB(Object inData)
ClassCastException
is thrown. An ArrayIndexOutOfBoundsException
is thrown if inData
is not large enough to hold a pixel value for this ColorModel
. The returned value will be in a non pre-multiplied format, i.e. if the alpha is premultiplied, this method will divide it out of the color components (if the alpha value is 0, the color values will be 0).inData
- the specified pixelpublic Object getDataElements(int rgb, Object pixel)
ColorModel
, given an integer pixel representation in the default RGB color model. This array can then be passed to the WritableRaster.setDataElements(int, int, java.lang.Object)
method of a WritableRaster
object. If the pixel variable is null
, a new array will be 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. If this transferType
is not supported, a UnsupportedOperationException
will be thrown. Since ColorModel
is an abstract class, any instance is an instance of a subclass. Subclasses must override this method since the implementation in this abstract class throws an UnsupportedOperationException
.rgb
- the integer pixel representation in the default RGB color modelpixel
- the specified pixelColorModel
.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 this method is not supported by this ColorModel
public int[] getComponents(int pixel, int[] components, int offset)
ColorModel
. The pixel value is specified as an int
. An IllegalArgumentException
will be thrown if pixel values for this ColorModel
are not conveniently representable as a single int
or if color component values for this ColorModel
are not conveniently representable in the unnormalized form. For example, this method can be used to retrieve the components for a specific pixel value in a DirectColorModel
. If the components array is null
, a new array will be allocated. The components array will be returned. 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). Since ColorModel
is an abstract class, any instance is an instance of a subclass. Subclasses must override this method since the implementation in this abstract class throws an UnsupportedOperationException
.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 componentsUnsupportedOperationException
- if this method is not supported by this ColorModel
public int[] getComponents(Object pixel, int[] components, int offset)
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 IllegalArgumentException
will be thrown if color component values for this ColorModel
are not conveniently representable in the unnormalized form. An ArrayIndexOutOfBoundsException
is thrown if pixel
is not large enough to hold a pixel value for this ColorModel
. This method can be used to retrieve the components for a specific pixel value in any ColorModel
. If the components array is null
, a new array will be allocated. The components array will be returned. 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
). Since ColorModel
is an abstract class, any instance is an instance of a subclass. Subclasses must override this method since the implementation in this abstract class throws an UnsupportedOperationException
.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 pixelUnsupportedOperationException
- if this method is not supported by this ColorModel
public int[] getUnnormalizedComponents(float[] normComponents, int normOffset, int[] components, int offset)
ColorSpace
object for this ColorModel
. An IllegalArgumentException
will be thrown if color component values for this ColorModel
are not conveniently representable in the unnormalized form. If the components
array is null
, a new array will be allocated. The components
array will be returned. 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
). An IllegalArgumentException
is thrown if the normComponents
array is not large enough to hold all the color and alpha components starting at normOffset
.normComponents
- an array containing normalized componentsnormOffset
- the offset into the normComponents
array at which to start retrieving normalized componentscomponents
- an array that receives the components from normComponents
offset
- the index into components
at which to begin storing normalized components from normComponents
IllegalArgumentException
- If the component values for this ColorModel
are not conveniently representable in the unnormalized form.IllegalArgumentException
- if the length of normComponents
minus normOffset
is less than numComponents
UnsupportedOperationException
- if the constructor of this ColorModel
called the super(bits)
constructor, but did not override this method. See the constructor, ColorModel(int)
.public float[] getNormalizedComponents(int[] components, int offset, float[] normComponents, int normOffset)
ColorSpace
object for this ColorModel
. An IllegalArgumentException
will be thrown if color component values for this ColorModel
are not conveniently representable in the unnormalized form. If the normComponents
array is null
, a new array will be allocated. The normComponents
array will be returned. Color/alpha components are stored in the normComponents
array starting at normOffset
(even if the array is allocated by this method). An ArrayIndexOutOfBoundsException
is thrown if the normComponents
array is not null
and is not large enough to hold all the color and alpha components (starting at normOffset
). An IllegalArgumentException
is thrown if the components
array is not large enough to hold all the color and alpha components starting at offset
. Since ColorModel
is an abstract class, any instance is an instance of a subclass. The default implementation of this method in this abstract class assumes that component values for this class are conveniently representable in the unnormalized form. Therefore, subclasses which may have instances which do not support the unnormalized form must override this method.
components
- an array containing unnormalized componentsoffset
- the offset into the components
array at which to start retrieving unnormalized componentsnormComponents
- an array that receives the normalized componentsnormOffset
- the index into normComponents
at which to begin storing normalized componentsIllegalArgumentException
- If the component values for this ColorModel
are not conveniently representable in the unnormalized form.UnsupportedOperationException
- if the constructor of this ColorModel
called the super(bits)
constructor, but did not override this method. See the constructor, ColorModel(int)
.UnsupportedOperationException
- if this method is unable to determine the number of bits per componentpublic int getDataElement(int[] components, int offset)
int
in this ColorModel
, given an array of unnormalized color/alpha components. This method will throw an IllegalArgumentException
if component values for this ColorModel
are not conveniently representable as a single int
or if color component values for this ColorModel
are not conveniently representable in the unnormalized form. An ArrayIndexOutOfBoundsException
is thrown if the components
array is not large enough to hold all the color and alpha components (starting at offset
). Since ColorModel
is an abstract class, any instance is an instance of a subclass. Subclasses must override this method since the implementation in this abstract class throws an UnsupportedOperationException
.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.IllegalArgumentException
- if pixel values for this ColorModel
are not conveniently representable as a single int
IllegalArgumentException
- if component values for this ColorModel
are not conveniently representable in the unnormalized formArrayIndexOutOfBoundsException
- if the components
array is not large enough to hold all of the color and alpha components starting at offset
UnsupportedOperationException
- if this method is not supported by this ColorModel
public Object getDataElements(int[] components, int offset, Object obj)
ColorModel
, given an array of unnormalized color/alpha components. This array can then be passed to the setDataElements
method of a WritableRaster
object. This method will throw an IllegalArgumentException
if color component values for this ColorModel
are not conveniently representable in the unnormalized form. An ArrayIndexOutOfBoundsException
is thrown if the components
array is not large enough to hold all the color and alpha components (starting at offset
). If the obj
variable is null
, a new array will be allocated. If obj
is not null
, it must be a primitive array of type transferType; otherwise, a ClassCastException
is thrown. An ArrayIndexOutOfBoundsException
is thrown if obj
is not large enough to hold a pixel value for this ColorModel
. Since ColorModel
is an abstract class, any instance is an instance of a subclass. Subclasses must override this method since the implementation in this abstract class throws an UnsupportedOperationException
.components
- an array of unnormalized color and alpha componentsoffset
- the index into components
at which to begin retrieving color and alpha componentsobj
- the Object
representing an array of color and alpha componentsObject
representing an array of color and alpha components.ClassCastException
- if obj
is not a primitive array of type transferType
ArrayIndexOutOfBoundsException
- if obj
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
IllegalArgumentException
- if component values for this ColorModel
are not conveniently representable in the unnormalized formUnsupportedOperationException
- if this method is not supported by this ColorModel
public int getDataElement(float[] normComponents, int normOffset)
int
in this ColorModel
, given an array of normalized color/alpha components. This method will throw an IllegalArgumentException
if pixel values for this ColorModel
are not conveniently representable as a single int
. An ArrayIndexOutOfBoundsException
is thrown if the normComponents
array is not large enough to hold all the color and alpha components (starting at normOffset
). Since ColorModel
is an abstract class, any instance is an instance of a subclass. The default implementation of this method in this abstract class first converts from the normalized form to the unnormalized form and then calls getDataElement(int[], int)
. Subclasses which may have instances which do not support the unnormalized form must override this method.normComponents
- an array of normalized color and alpha componentsnormOffset
- the index into normComponents
at which to begin retrieving the color and alpha componentsint
pixel value in this ColorModel
corresponding to the specified components.IllegalArgumentException
- if pixel values for this ColorModel
are not conveniently representable as a single int
ArrayIndexOutOfBoundsException
- if the normComponents
array is not large enough to hold all of the color and alpha components starting at normOffset
public Object getDataElements(float[] normComponents, int normOffset, Object obj)
ColorModel
, given an array of normalized color/alpha components. This array can then be passed to the setDataElements
method of a WritableRaster
object. An ArrayIndexOutOfBoundsException
is thrown if the normComponents
array is not large enough to hold all the color and alpha components (starting at normOffset
). If the obj
variable is null
, a new array will be allocated. If obj
is not null
, it must be a primitive array of type transferType; otherwise, a ClassCastException
is thrown. An ArrayIndexOutOfBoundsException
is thrown if obj
is not large enough to hold a pixel value for this ColorModel
. Since ColorModel
is an abstract class, any instance is an instance of a subclass. The default implementation of this method in this abstract class first converts from the normalized form to the unnormalized form and then calls getDataElement(int[], int, Object)
. Subclasses which may have instances which do not support the unnormalized form must override this method.normComponents
- an array of normalized color and alpha componentsnormOffset
- the index into normComponents
at which to begin retrieving color and alpha componentsobj
- a primitive data array to hold the returned pixelObject
which is a primitive data array representation of a pixelClassCastException
- if obj
is not a primitive array of type transferType
ArrayIndexOutOfBoundsException
- if obj
is not large enough to hold a pixel value for this ColorModel
or the normComponents
array is not large enough to hold all of the color and alpha components starting at normOffset
public float[] getNormalizedComponents(Object pixel, float[] normComponents, int normOffset)
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
. Normalized components are float values between a per component minimum and maximum specified by the ColorSpace
object for this ColorModel
. If the normComponents
array is null
, a new array will be allocated. The normComponents
array will be returned. Color/alpha components are stored in the normComponents
array starting at normOffset
(even if the array is allocated by this method). An ArrayIndexOutOfBoundsException
is thrown if the normComponents
array is not null
and is not large enough to hold all the color and alpha components (starting at normOffset
). Since ColorModel
is an abstract class, any instance is an instance of a subclass. The default implementation of this method in this abstract class first retrieves color and alpha components in the unnormalized form using getComponents(Object, int[], int)
and then calls getNormalizedComponents(int[], int, float[], int)
. Subclasses which may have instances which do not support the unnormalized form must override this method.pixel
- the specified pixelnormComponents
- an array to receive the normalized componentsnormOffset
- the offset into the normComponents
array at which to start storing normalized componentsClassCastException
- if pixel
is not a primitive array of type transferTypeArrayIndexOutOfBoundsException
- if normComponents
is not large enough to hold all color and alpha components starting at normOffset
ArrayIndexOutOfBoundsException
- if pixel
is not large enough to hold a pixel value for this ColorModel
.UnsupportedOperationException
- if the constructor of this ColorModel
called the super(bits)
constructor, but did not override this method. See the constructor, ColorModel(int)
.UnsupportedOperationException
- if this method is unable to determine the number of bits per componentpublic boolean equals(Object obj)
Object
which is identical to an ==
test since this class cannot enforce the issues of a proper equality test among multiple independent subclass branches. Subclasses are encouraged to override this method and provide equality testing for their own properties in addition to equality tests for the following common base properties of ColorModel
: ColorSpace
type.public int hashCode()
Object
which returns the system ID for the class. Subclasses are encouraged to override this method and provide a hash for their own properties in addition to hashing the values of the following common base properties of ColorModel
: ColorSpace
type.public final ColorSpace getColorSpace()
ColorSpace
associated with this ColorModel
.ColorSpace
of this ColorModel
.public ColorModel coerceData(WritableRaster raster, boolean isAlphaPremultiplied)
isAlphaPremultiplied
variable, assuming the data is currently correctly described by this ColorModel
. It may multiply or divide the color raster data by alpha, or do nothing if the data is in the correct state. If the data needs to be coerced, this method will also return an instance of this ColorModel
with the isAlphaPremultiplied
flag set appropriately. This method will throw a UnsupportedOperationException
if it is not supported by this ColorModel
. Since ColorModel
is an abstract class, any instance is an instance of a subclass. Subclasses must override this method since the implementation in this abstract class throws an UnsupportedOperationException
.raster
- the WritableRaster
dataisAlphaPremultiplied
- true
if the alpha is premultiplied; false
otherwiseColorModel
object that represents the coerced data.public boolean isCompatibleRaster(Raster raster)
true
if raster
is compatible with this ColorModel
and false
if it is not. Since ColorModel
is an abstract class, any instance is an instance of a subclass. Subclasses must override this method since the implementation in this abstract class throws an UnsupportedOperationException
.raster
- the Raster
object to test for compatibilitytrue
if raster
is compatible with this ColorModel
.UnsupportedOperationException
- if this method has not been implemented for this ColorModel
public WritableRaster createCompatibleWritableRaster(int w, int h)
WritableRaster
with the specified width and height that has a data layout (SampleModel
) compatible with this ColorModel
. Since ColorModel
is an abstract class, any instance is an instance of a subclass. Subclasses must override this method since the implementation in this abstract class throws an UnsupportedOperationException
.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 this method is not supported by this ColorModel
public SampleModel createCompatibleSampleModel(int w, int h)
SampleModel
with the specified width and height that has a data layout compatible with this ColorModel
. Since ColorModel
is an abstract class, any instance is an instance of a subclass. Subclasses must override this method since the implementation in this abstract class throws an UnsupportedOperationException
.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.UnsupportedOperationException
- if this method is not supported by this ColorModel
public boolean isCompatibleSampleModel(SampleModel sm)
SampleModel
is compatible with this ColorModel
. Since ColorModel
is an abstract class, any instance is an instance of a subclass. Subclasses must override this method since the implementation in this abstract class throws an UnsupportedOperationException
.sm
- the specified SampleModel
true
if the specified SampleModel
is compatible with this ColorModel
; false
otherwise.UnsupportedOperationException
- if this method is not supported by this ColorModel
public WritableRaster getAlphaRaster(WritableRaster raster)
Raster
representing the alpha channel of an image, extracted from the input Raster
, provided that pixel values of this ColorModel
represent color and alpha information as separate spatial bands (e.g. ComponentColorModel
and DirectColorModel
). This method assumes that Raster
objects associated with such a ColorModel
store the alpha band, if present, as the last band of image data. Returns null
if there is no separate spatial alpha channel associated with this ColorModel
. If this is an IndexColorModel
which has alpha in the lookup table, this method will return null
since there is no spatially discrete alpha channel. This method will create a new Raster
(but will share the data array). Since ColorModel
is an abstract class, any instance is an instance of a subclass. Subclasses must override this method to get any behavior other than returning null
because the implementation in this abstract class returns null
.raster
- the specified Raster
Raster
representing the alpha channel of an image, obtained from the specified Raster
.public String toString()
String
representation of 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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https://docs.oracle.com/en/java/javase/21/docs/api/java.desktop/java/awt/image/ColorModel.html