Module java.desktop

Package java.awt.image

Class BufferedImage

java.lang.Object

java.awt.Image

java.awt.image.BufferedImage

All Implemented Interfaces:

RenderedImage, WritableRenderedImage, Transparency

public class BufferedImage
extends Image
implements WritableRenderedImage, Transparency

The BufferedImage subclass describes an Image with an accessible buffer of image data. A BufferedImage is comprised of a ColorModel and a Raster of image data. The number and types of bands in the SampleModel of the Raster must match the number and types required by the ColorModel to represent its color and alpha components. All BufferedImage objects have an upper left corner coordinate of (0, 0). Any Raster used to construct a BufferedImage must therefore have minX=0 and minY=0.

This class relies on the data fetching and setting methods of Raster, and on the color characterization methods of ColorModel.

See Also:

• ColorModel
• Raster
• WritableRaster

Field Summary

Fields

Modifier and Type	Field	Description
static final int	TYPE_3BYTE_BGR	Represents an image with 8-bit RGB color components, corresponding to a Windows-style BGR color model) with the colors Blue, Green, and Red stored in 3 bytes.
static final int	TYPE_4BYTE_ABGR	Represents an image with 8-bit RGBA color components with the colors Blue, Green, and Red stored in 3 bytes and 1 byte of alpha.
static final int	TYPE_4BYTE_ABGR_PRE	Represents an image with 8-bit RGBA color components with the colors Blue, Green, and Red stored in 3 bytes and 1 byte of alpha.
static final int	TYPE_BYTE_BINARY	Represents an opaque byte-packed 1, 2, or 4 bit image.
static final int	TYPE_BYTE_GRAY	Represents a unsigned byte grayscale image, non-indexed.
static final int	TYPE_BYTE_INDEXED	Represents an indexed byte image.
static final int	TYPE_CUSTOM	Image type is not recognized so it must be a customized image.
static final int	TYPE_INT_ARGB	Represents an image with 8-bit RGBA color components packed into integer pixels.
static final int	TYPE_INT_ARGB_PRE	Represents an image with 8-bit RGBA color components packed into integer pixels.
static final int	TYPE_INT_BGR	Represents an image with 8-bit RGB color components, corresponding to a Windows- or Solaris- style BGR color model, with the colors Blue, Green, and Red packed into integer pixels.
static final int	TYPE_INT_RGB	Represents an image with 8-bit RGB color components packed into integer pixels.
static final int	TYPE_USHORT_555_RGB	Represents an image with 5-5-5 RGB color components (5-bits red, 5-bits green, 5-bits blue) with no alpha.
static final int	TYPE_USHORT_565_RGB	Represents an image with 5-6-5 RGB color components (5-bits red, 6-bits green, 5-bits blue) with no alpha.
static final int	TYPE_USHORT_GRAY	Represents an unsigned short grayscale image, non-indexed).

Fields declared in class java.awt.Image

accelerationPriority, SCALE_AREA_AVERAGING, SCALE_DEFAULT, SCALE_FAST, SCALE_REPLICATE, SCALE_SMOOTH, UndefinedProperty

Fields declared in interface java.awt.Transparency

BITMASK, OPAQUE, TRANSLUCENT

Constructor Summary

Constructors

Constructor	Description
BufferedImage(int width, int height, int imageType)	Constructs a BufferedImage of one of the predefined image types.
BufferedImage(int width, int height, int imageType, IndexColorModel cm)	Constructs a BufferedImage of one of the predefined image types: TYPE_BYTE_BINARY or TYPE_BYTE_INDEXED.
BufferedImage(ColorModel cm, WritableRaster raster, boolean isRasterPremultiplied, Hashtable<?,?> properties)	Constructs a new BufferedImage with a specified ColorModel and Raster.

Method Summary

Modifier and Type	Method	Description
void	addTileObserver(TileObserver to)	Adds a tile observer.
void	coerceData(boolean isAlphaPremultiplied)	Forces the data to match the state specified in the isAlphaPremultiplied variable.
WritableRaster	copyData(WritableRaster outRaster)	Computes an arbitrary rectangular region of the BufferedImage and copies it into a specified WritableRaster.
Graphics2D	createGraphics()	Creates a Graphics2D, which can be used to draw into this BufferedImage.
WritableRaster	getAlphaRaster()	Returns a WritableRaster representing the alpha channel for BufferedImage objects with ColorModel objects that support a separate spatial alpha channel, such as ComponentColorModel and DirectColorModel.
ColorModel	getColorModel()	Returns the ColorModel.
Raster	getData()	Returns the image as one large tile.
Raster	getData(Rectangle rect)	Computes and returns an arbitrary region of the BufferedImage.
Graphics	getGraphics()	This method returns a Graphics2D, but is here for backwards compatibility.
int	getHeight()	Returns the height of the BufferedImage.
int	getHeight(ImageObserver observer)	Returns the height of the BufferedImage.
int	getMinTileX()	Returns the minimum tile index in the x direction.
int	getMinTileY()	Returns the minimum tile index in the y direction.
int	getMinX()	Returns the minimum x coordinate of this BufferedImage.
int	getMinY()	Returns the minimum y coordinate of this BufferedImage.
int	getNumXTiles()	Returns the number of tiles in the x direction.
int	getNumYTiles()	Returns the number of tiles in the y direction.
Object	getProperty(String name)	Returns a property of the image by name.
Object	getProperty(String name, ImageObserver observer)	Returns a property of the image by name.
String[]	getPropertyNames()	Returns an array of names recognized by getProperty(String) or null, if no property names are recognized.
WritableRaster	getRaster()	Returns the WritableRaster.
int	getRGB(int x, int y)	Returns an integer pixel in the default RGB color model (TYPE_INT_ARGB) and default sRGB colorspace.
int[]	getRGB(int startX, int startY, int w, int h, int[] rgbArray, int offset, int scansize)	Returns an array of integer pixels in the default RGB color model (TYPE_INT_ARGB) and default sRGB color space, from a portion of the image data.
SampleModel	getSampleModel()	Returns the SampleModel associated with this BufferedImage.
ImageProducer	getSource()	Returns the object that produces the pixels for the image.
Vector<RenderedImage>	getSources()	Returns a Vector of RenderedImage objects that are the immediate sources, not the sources of these immediate sources, of image data for this BufferedImage.
BufferedImage	getSubimage(int x, int y, int w, int h)	Returns a subimage defined by a specified rectangular region.
Raster	getTile(int tileX, int tileY)	Returns tile (tileX, tileY).
int	getTileGridXOffset()	Returns the x offset of the tile grid relative to the origin, For example, the x coordinate of the location of tile (0, 0).
int	getTileGridYOffset()	Returns the y offset of the tile grid relative to the origin, For example, the y coordinate of the location of tile (0, 0).
int	getTileHeight()	Returns the tile height in pixels.
int	getTileWidth()	Returns the tile width in pixels.
int	getTransparency()	Returns the transparency.
int	getType()	Returns the image type.
int	getWidth()	Returns the width of the BufferedImage.
int	getWidth(ImageObserver observer)	Returns the width of the BufferedImage.
WritableRaster	getWritableTile(int tileX, int tileY)	Checks out a tile for writing.
Point[]	getWritableTileIndices()	Returns an array of Point objects indicating which tiles are checked out for writing.
boolean	hasTileWriters()	Returns whether or not any tile is checked out for writing.
boolean	isAlphaPremultiplied()	Returns whether or not the alpha has been premultiplied.
boolean	isTileWritable(int tileX, int tileY)	Returns whether or not a tile is currently checked out for writing.
void	releaseWritableTile(int tileX, int tileY)	Relinquishes permission to write to a tile.
void	removeTileObserver(TileObserver to)	Removes a tile observer.
void	setData(Raster r)	Sets a rectangular region of the image to the contents of the specified Raster r, which is assumed to be in the same coordinate space as the BufferedImage.
void	setRGB(int x, int y, int rgb)	Sets a pixel in this BufferedImage to the specified RGB value.
void	setRGB(int startX, int startY, int w, int h, int[] rgbArray, int offset, int scansize)	Sets an array of integer pixels in the default RGB color model (TYPE_INT_ARGB) and default sRGB color space, into a portion of the image data.
String	toString()	Returns a String representation of this BufferedImage object and its values.

Methods declared in class java.awt.Image

flush, getAccelerationPriority, getCapabilities, getScaledInstance, setAccelerationPriority

Methods declared in class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Details

TYPE_CUSTOM

public static final int TYPE_CUSTOM

Image type is not recognized so it must be a customized image. This type is only used as a return value for the getType() method.

See Also:

• Constant Field Values

TYPE_INT_RGB

public static final int TYPE_INT_RGB

Represents an image with 8-bit RGB color components packed into integer pixels. The image has a DirectColorModel without alpha. When data with non-opaque alpha is stored in an image of this type, the color data must be adjusted to a non-premultiplied form and the alpha discarded, as described in the AlphaComposite documentation.

See Also:

• Constant Field Values

TYPE_INT_ARGB

public static final int TYPE_INT_ARGB

Represents an image with 8-bit RGBA color components packed into integer pixels. The image has a DirectColorModel with alpha. The color data in this image is considered not to be premultiplied with alpha. When this type is used as the imageType argument to a BufferedImage constructor, the created image is consistent with images created in the JDK1.1 and earlier releases.

See Also:

• Constant Field Values

TYPE_INT_ARGB_PRE

public static final int TYPE_INT_ARGB_PRE

Represents an image with 8-bit RGBA color components packed into integer pixels. The image has a DirectColorModel with alpha. The color data in this image is considered to be premultiplied with alpha.

See Also:

• Constant Field Values

TYPE_INT_BGR

public static final int TYPE_INT_BGR

Represents an image with 8-bit RGB color components, corresponding to a Windows- or Solaris- style BGR color model, with the colors Blue, Green, and Red packed into integer pixels. There is no alpha. The image has a DirectColorModel. When data with non-opaque alpha is stored in an image of this type, the color data must be adjusted to a non-premultiplied form and the alpha discarded, as described in the AlphaComposite documentation.

See Also:

• Constant Field Values

TYPE_3BYTE_BGR

public static final int TYPE_3BYTE_BGR

Represents an image with 8-bit RGB color components, corresponding to a Windows-style BGR color model) with the colors Blue, Green, and Red stored in 3 bytes. There is no alpha. The image has a ComponentColorModel. When data with non-opaque alpha is stored in an image of this type, the color data must be adjusted to a non-premultiplied form and the alpha discarded, as described in the AlphaComposite documentation.

See Also:

• Constant Field Values

TYPE_4BYTE_ABGR

public static final int TYPE_4BYTE_ABGR

Represents an image with 8-bit RGBA color components with the colors Blue, Green, and Red stored in 3 bytes and 1 byte of alpha. The image has a ComponentColorModel with alpha. The color data in this image is considered not to be premultiplied with alpha. The byte data is interleaved in a single byte array in the order A, B, G, R from lower to higher byte addresses within each pixel.

See Also:

• Constant Field Values

TYPE_4BYTE_ABGR_PRE

public static final int TYPE_4BYTE_ABGR_PRE

Represents an image with 8-bit RGBA color components with the colors Blue, Green, and Red stored in 3 bytes and 1 byte of alpha. The image has a ComponentColorModel with alpha. The color data in this image is considered to be premultiplied with alpha. The byte data is interleaved in a single byte array in the order A, B, G, R from lower to higher byte addresses within each pixel.

See Also:

• Constant Field Values

TYPE_USHORT_565_RGB

public static final int TYPE_USHORT_565_RGB

Represents an image with 5-6-5 RGB color components (5-bits red, 6-bits green, 5-bits blue) with no alpha. This image has a DirectColorModel. When data with non-opaque alpha is stored in an image of this type, the color data must be adjusted to a non-premultiplied form and the alpha discarded, as described in the AlphaComposite documentation.

See Also:

• Constant Field Values

TYPE_USHORT_555_RGB

public static final int TYPE_USHORT_555_RGB

Represents an image with 5-5-5 RGB color components (5-bits red, 5-bits green, 5-bits blue) with no alpha. This image has a DirectColorModel. When data with non-opaque alpha is stored in an image of this type, the color data must be adjusted to a non-premultiplied form and the alpha discarded, as described in the AlphaComposite documentation.

See Also:

• Constant Field Values

TYPE_BYTE_GRAY

public static final int TYPE_BYTE_GRAY

Represents a unsigned byte grayscale image, non-indexed. This image has a ComponentColorModel with a CS_GRAY ColorSpace. When data with non-opaque alpha is stored in an image of this type, the color data must be adjusted to a non-premultiplied form and the alpha discarded, as described in the AlphaComposite documentation.

See Also:

• Constant Field Values

TYPE_USHORT_GRAY

public static final int TYPE_USHORT_GRAY

Represents an unsigned short grayscale image, non-indexed). This image has a ComponentColorModel with a CS_GRAY ColorSpace. When data with non-opaque alpha is stored in an image of this type, the color data must be adjusted to a non-premultiplied form and the alpha discarded, as described in the AlphaComposite documentation.

See Also:

• Constant Field Values

TYPE_BYTE_BINARY

public static final int TYPE_BYTE_BINARY

Represents an opaque byte-packed 1, 2, or 4 bit image. The image has an IndexColorModel without alpha. When this type is used as the imageType argument to the BufferedImage constructor that takes an imageType argument but no ColorModel argument, a 1-bit image is created with an IndexColorModel with two colors in the default sRGB ColorSpace: {0, 0, 0} and {255, 255, 255}.

Images with 2 or 4 bits per pixel may be constructed via the BufferedImage constructor that takes a ColorModel argument by supplying a ColorModel with an appropriate map size.

Images with 8 bits per pixel should use the image types TYPE_BYTE_INDEXED or TYPE_BYTE_GRAY depending on their ColorModel.

When color data is stored in an image of this type, the closest color in the colormap is determined by the IndexColorModel and the resulting index is stored. Approximation and loss of alpha or color components can result, depending on the colors in the IndexColorModel colormap.

See Also:

• Constant Field Values

TYPE_BYTE_INDEXED

public static final int TYPE_BYTE_INDEXED

Represents an indexed byte image. When this type is used as the imageType argument to the BufferedImage constructor that takes an imageType argument but no ColorModel argument, an IndexColorModel is created with a 256-color 6/6/6 color cube palette with the rest of the colors from 216-255 populated by grayscale values in the default sRGB ColorSpace.

When color data is stored in an image of this type, the closest color in the colormap is determined by the IndexColorModel and the resulting index is stored. Approximation and loss of alpha or color components can result, depending on the colors in the IndexColorModel colormap.

See Also:

• Constant Field Values

Constructor Details

BufferedImage

public BufferedImage(int width,
 int height,
 int imageType)

Constructs a BufferedImage of one of the predefined image types. The ColorSpace for the image is the default sRGB space.

Parameters:

width - width of the created image

height - height of the created image

imageType - type of the created image

See Also:

• ColorSpace
• TYPE_INT_RGB
• TYPE_INT_ARGB
• TYPE_INT_ARGB_PRE
• TYPE_INT_BGR
• TYPE_3BYTE_BGR
• TYPE_4BYTE_ABGR
• TYPE_4BYTE_ABGR_PRE
• TYPE_BYTE_GRAY
• TYPE_USHORT_GRAY
• TYPE_BYTE_BINARY
• TYPE_BYTE_INDEXED
• TYPE_USHORT_565_RGB
• TYPE_USHORT_555_RGB

BufferedImage

public BufferedImage(int width,
 int height,
 int imageType,
 IndexColorModel cm)

Constructs a BufferedImage of one of the predefined image types: TYPE_BYTE_BINARY or TYPE_BYTE_INDEXED.

If the image type is TYPE_BYTE_BINARY, the number of entries in the color model is used to determine whether the image should have 1, 2, or 4 bits per pixel. If the color model has 1 or 2 entries, the image will have 1 bit per pixel. If it has 3 or 4 entries, the image with have 2 bits per pixel. If it has between 5 and 16 entries, the image will have 4 bits per pixel. Otherwise, an IllegalArgumentException will be thrown.

Parameters:

width - width of the created image

height - height of the created image

imageType - type of the created image

cm - IndexColorModel of the created image

Throws:

IllegalArgumentException - if the imageType is not TYPE_BYTE_BINARY or TYPE_BYTE_INDEXED or if the imageType is TYPE_BYTE_BINARY and the color map has more than 16 entries.

See Also:

• TYPE_BYTE_BINARY
• TYPE_BYTE_INDEXED

BufferedImage

public BufferedImage(ColorModel cm,
 WritableRaster raster,
 boolean isRasterPremultiplied,
 Hashtable<?,?> properties)

Constructs a new BufferedImage with a specified ColorModel and Raster. If the number and types of bands in the SampleModel of the Raster do not match the number and types required by the ColorModel to represent its color and alpha components, a RasterFormatException is thrown. This method can multiply or divide the color Raster data by alpha to match the alphaPremultiplied state in the ColorModel. Properties for this BufferedImage can be established by passing in a Hashtable of String/Object pairs.

Parameters:

cm - ColorModel for the new image

raster - Raster for the image data

isRasterPremultiplied - if true, the data in the raster has been premultiplied with alpha.

properties - Hashtable of String/Object pairs.

Throws:

RasterFormatException - if the number and types of bands in the SampleModel of the Raster do not match the number and types required by the ColorModel to represent its color and alpha components.

IllegalArgumentException - if raster is incompatible with cm

See Also:

• ColorModel
• Raster
• WritableRaster

Method Details

getType

public int getType()

Returns the image type. If it is not one of the known types, TYPE_CUSTOM is returned.

Returns:

the image type of this BufferedImage.

See Also:

• TYPE_INT_RGB
• TYPE_INT_ARGB
• TYPE_INT_ARGB_PRE
• TYPE_INT_BGR
• TYPE_3BYTE_BGR
• TYPE_4BYTE_ABGR
• TYPE_4BYTE_ABGR_PRE
• TYPE_BYTE_GRAY
• TYPE_BYTE_BINARY
• TYPE_BYTE_INDEXED
• TYPE_USHORT_GRAY
• TYPE_USHORT_565_RGB
• TYPE_USHORT_555_RGB
• TYPE_CUSTOM

getColorModel

public ColorModel getColorModel()

Returns the ColorModel.

Specified by:

getColorModel in interface RenderedImage

Returns:

the ColorModel of this BufferedImage.

getRaster

public WritableRaster getRaster()

Returns the WritableRaster.

Returns:

the WritableRaster of this BufferedImage.

getAlphaRaster

public WritableRaster getAlphaRaster()

Returns a WritableRaster representing the alpha channel for BufferedImage objects with ColorModel objects that support a separate spatial alpha channel, such as ComponentColorModel and DirectColorModel. Returns null if there is no alpha channel associated with the ColorModel in this image. This method assumes that for all ColorModel objects other than IndexColorModel, if the ColorModel supports alpha, there is a separate alpha channel which is stored as the last band of image data. If the image uses an IndexColorModel that has alpha in the lookup table, this method returns null since there is no spatially discrete alpha channel. This method creates a new WritableRaster, but shares the data array.

Returns:

a WritableRaster or null if this BufferedImage has no alpha channel associated with its ColorModel.

getRGB

public int getRGB(int x,
 int y)

Returns an integer pixel in the default RGB color model (TYPE_INT_ARGB) and default sRGB colorspace. Color conversion takes place if this default model does not match the image ColorModel. There are only 8-bits of precision for each color component in the returned data when using this method.

An ArrayOutOfBoundsException may be thrown if the coordinates are not in bounds. However, explicit bounds checking is not guaranteed.

Parameters:

x - the X coordinate of the pixel from which to get the pixel in the default RGB color model and sRGB color space

y - the Y coordinate of the pixel from which to get the pixel in the default RGB color model and sRGB color space

Returns:

an integer pixel in the default RGB color model and default sRGB colorspace.

See Also:

• setRGB(int, int, int)
• setRGB(int, int, int, int, int[], int, int)

getRGB

public int[] getRGB(int startX,
 int startY,
 int w,
 int h,
 int[] rgbArray,
 int offset,
 int scansize)

Returns an array of integer pixels in the default RGB color model (TYPE_INT_ARGB) and default sRGB color space, from a portion of the image data. Color conversion takes place if the default model does not match the image ColorModel. There are only 8-bits of precision for each color component in the returned data when using this method. With a specified coordinate (x, y) in the image, the ARGB pixel can be accessed in this way:

    pixel   = rgbArray[offset + (y-startY)*scansize + (x-startX)]; 

An ArrayOutOfBoundsException may be thrown if the region is not in bounds. However, explicit bounds checking is not guaranteed.

Parameters:

startX - the starting X coordinate

startY - the starting Y coordinate

w - width of region

h - height of region

rgbArray - if not null, the rgb pixels are written here

offset - offset into the rgbArray

scansize - scanline stride for the rgbArray

Returns:

array of RGB pixels.

See Also:

• setRGB(int, int, int)
• setRGB(int, int, int, int, int[], int, int)

setRGB

public void setRGB(int x,
 int y,
 int rgb)

Sets a pixel in this BufferedImage to the specified RGB value. The pixel is assumed to be in the default RGB color model, TYPE_INT_ARGB, and default sRGB color space. For images with an IndexColorModel, the index with the nearest color is chosen.

An ArrayOutOfBoundsException may be thrown if the coordinates are not in bounds. However, explicit bounds checking is not guaranteed.

Parameters:

x - the X coordinate of the pixel to set

y - the Y coordinate of the pixel to set

rgb - the RGB value

See Also:

• getRGB(int, int)
• getRGB(int, int, int, int, int[], int, int)

setRGB

public void setRGB(int startX,
 int startY,
 int w,
 int h,
 int[] rgbArray,
 int offset,
 int scansize)

Sets an array of integer pixels in the default RGB color model (TYPE_INT_ARGB) and default sRGB color space, into a portion of the image data. Color conversion takes place if the default model does not match the image ColorModel. There are only 8-bits of precision for each color component in the returned data when using this method. With a specified coordinate (x, y) in the this image, the ARGB pixel can be accessed in this way:

    pixel   = rgbArray[offset + (y-startY)*scansize + (x-startX)];
 

WARNING: No dithering takes place.

An ArrayOutOfBoundsException may be thrown if the region is not in bounds. However, explicit bounds checking is not guaranteed.

Parameters:

startX - the starting X coordinate

startY - the starting Y coordinate

w - width of the region

h - height of the region

rgbArray - the rgb pixels

offset - offset into the rgbArray

scansize - scanline stride for the rgbArray

See Also:

• getRGB(int, int)
• getRGB(int, int, int, int, int[], int, int)

getWidth

public int getWidth()

Returns the width of the BufferedImage.

Specified by:

getWidth in interface RenderedImage

Returns:

the width of this BufferedImage

getHeight

public int getHeight()

Returns the height of the BufferedImage.

Specified by:

getHeight in interface RenderedImage

Returns:

the height of this BufferedImage

getWidth

public int getWidth(ImageObserver observer)

Returns the width of the BufferedImage.

Specified by:

getWidth in class Image

Parameters:

observer - ignored

Returns:

the width of this BufferedImage

See Also:

• Image.getHeight(java.awt.image.ImageObserver)
• ImageObserver

getHeight

public int getHeight(ImageObserver observer)

Returns the height of the BufferedImage.

Specified by:

getHeight in class Image

Parameters:

observer - ignored

Returns:

the height of this BufferedImage

See Also:

• Image.getWidth(java.awt.image.ImageObserver)
• ImageObserver

getSource

public ImageProducer getSource()

Returns the object that produces the pixels for the image.

Specified by:

getSource in class Image

Returns:

the ImageProducer that is used to produce the pixels for this image.

See Also:

• ImageProducer

getProperty

public Object getProperty(String name,
 ImageObserver observer)

Returns a property of the image by name. Individual property names are defined by the various image formats. If a property is not defined for a particular image, this method returns the UndefinedProperty field. If the properties for this image are not yet known, then this method returns null and the ImageObserver object is notified later. The property name "comment" should be used to store an optional comment that can be presented to the user as a description of the image, its source, or its author.

Specified by:

getProperty in class Image

Parameters:

name - the property name

observer - the ImageObserver that receives notification regarding image information

Returns:

an Object that is the property referred to by the specified name or null if the properties of this image are not yet known.

Throws:

NullPointerException - if the property name is null.

See Also:

• ImageObserver
• Image.UndefinedProperty

getProperty

public Object getProperty(String name)

Returns a property of the image by name.

Specified by:

getProperty in interface RenderedImage

Parameters:

name - the property name

Returns:

an Object that is the property referred to by the specified name.

Throws:

NullPointerException - if the property name is null.

See Also:

• Image.UndefinedProperty

getGraphics

public Graphics getGraphics()

This method returns a Graphics2D, but is here for backwards compatibility. createGraphics is more convenient, since it is declared to return a Graphics2D.

Specified by:

getGraphics in class Image

Returns:

a Graphics2D, which can be used to draw into this image.

See Also:

• Graphics
• Component.createImage(int, int)

createGraphics

public Graphics2D createGraphics()

Creates a Graphics2D, which can be used to draw into this BufferedImage.

Returns:

a Graphics2D, used for drawing into this image.

getSubimage

public BufferedImage getSubimage(int x,
 int y,
 int w,
 int h)

Returns a subimage defined by a specified rectangular region. The returned BufferedImage shares the same data array as the original image.

Parameters:

x - the X coordinate of the upper-left corner of the specified rectangular region

y - the Y coordinate of the upper-left corner of the specified rectangular region

w - the width of the specified rectangular region

h - the height of the specified rectangular region

Returns:

a BufferedImage that is the subimage of this BufferedImage.

Throws:

RasterFormatException - if the specified area is not contained within this BufferedImage.

isAlphaPremultiplied

public boolean isAlphaPremultiplied()

Returns whether or not the alpha has been premultiplied. It returns false if there is no alpha.

Returns:

true if the alpha has been premultiplied; false otherwise.

coerceData

public void coerceData(boolean isAlphaPremultiplied)

Forces the data to match the state specified in the isAlphaPremultiplied variable. It may multiply or divide the color raster data by alpha, or do nothing if the data is in the correct state.

Parameters:

isAlphaPremultiplied - true if the alpha has been premultiplied; false otherwise.

toString

public String toString()

Returns a String representation of this BufferedImage object and its values.

Overrides:

toString in class Object

Returns:

a String representing this BufferedImage.

getSources

public Vector<RenderedImage> getSources()

Returns a Vector of RenderedImage objects that are the immediate sources, not the sources of these immediate sources, of image data for this BufferedImage. This method returns null if the BufferedImage has no information about its immediate sources. It returns an empty Vector if the BufferedImage has no immediate sources.

Specified by:

getSources in interface RenderedImage

Returns:

a Vector containing immediate sources of this BufferedImage object's image date, or null if this BufferedImage has no information about its immediate sources, or an empty Vector if this BufferedImage has no immediate sources.

getPropertyNames

public String[] getPropertyNames()

Returns an array of names recognized by getProperty(String) or null, if no property names are recognized.

Specified by:

getPropertyNames in interface RenderedImage

Returns:

a String array containing all of the property names that getProperty(String) recognizes; or null if no property names are recognized.

getMinX

public int getMinX()

Returns the minimum x coordinate of this BufferedImage. This is always zero.

Specified by:

getMinX in interface RenderedImage

Returns:

the minimum x coordinate of this BufferedImage.

getMinY

public int getMinY()

Returns the minimum y coordinate of this BufferedImage. This is always zero.

Specified by:

getMinY in interface RenderedImage

Returns:

the minimum y coordinate of this BufferedImage.

getSampleModel

public SampleModel getSampleModel()

Returns the SampleModel associated with this BufferedImage.

Specified by:

getSampleModel in interface RenderedImage

Returns:

the SampleModel of this BufferedImage.

getNumXTiles

public int getNumXTiles()

Returns the number of tiles in the x direction. This is always one.

Specified by:

getNumXTiles in interface RenderedImage

Returns:

the number of tiles in the x direction.

getNumYTiles

public int getNumYTiles()

Returns the number of tiles in the y direction. This is always one.

Specified by:

getNumYTiles in interface RenderedImage

Returns:

the number of tiles in the y direction.

getMinTileX

public int getMinTileX()

Returns the minimum tile index in the x direction. This is always zero.

Specified by:

getMinTileX in interface RenderedImage

Returns:

the minimum tile index in the x direction.

getMinTileY

public int getMinTileY()

Returns the minimum tile index in the y direction. This is always zero.

Specified by:

getMinTileY in interface RenderedImage

Returns:

the minimum tile index in the y direction.

getTileWidth

public int getTileWidth()

Returns the tile width in pixels.

Specified by:

getTileWidth in interface RenderedImage

Returns:

the tile width in pixels.

getTileHeight

public int getTileHeight()

Returns the tile height in pixels.

Specified by:

getTileHeight in interface RenderedImage

Returns:

the tile height in pixels.

getTileGridXOffset

public int getTileGridXOffset()

Returns the x offset of the tile grid relative to the origin, For example, the x coordinate of the location of tile (0, 0). This is always zero.

Specified by:

getTileGridXOffset in interface RenderedImage

Returns:

the x offset of the tile grid.

getTileGridYOffset

public int getTileGridYOffset()

Returns the y offset of the tile grid relative to the origin, For example, the y coordinate of the location of tile (0, 0). This is always zero.

Specified by:

getTileGridYOffset in interface RenderedImage

Returns:

the y offset of the tile grid.

getTile

public Raster getTile(int tileX,
 int tileY)

Returns tile (tileX, tileY). Note that tileX and tileY are indices into the tile array, not pixel locations. The Raster that is returned is live, which means that it is updated if the image is changed.

Specified by:

getTile in interface RenderedImage

Parameters:

tileX - the x index of the requested tile in the tile array

tileY - the y index of the requested tile in the tile array

Returns:

a Raster that is the tile defined by the arguments tileX and tileY.

Throws:

ArrayIndexOutOfBoundsException - if both tileX and tileY are not equal to 0

getData

public Raster getData()

Returns the image as one large tile. The Raster returned is a copy of the image data is not updated if the image is changed.

Specified by:

getData in interface RenderedImage

Returns:

a Raster that is a copy of the image data.

See Also:

• setData(Raster)

getData

public Raster getData(Rectangle rect)

Computes and returns an arbitrary region of the BufferedImage. The Raster returned is a copy of the image data and is not updated if the image is changed.

Specified by:

getData in interface RenderedImage

Parameters:

rect - the region of the BufferedImage to be returned.

Returns:

a Raster that is a copy of the image data of the specified region of the BufferedImage

See Also:

• setData(Raster)

copyData

public WritableRaster copyData(WritableRaster outRaster)

Computes an arbitrary rectangular region of the BufferedImage and copies it into a specified WritableRaster. The region to be computed is determined from the bounds of the specified WritableRaster. The specified WritableRaster must have a SampleModel that is compatible with this image. If outRaster is null, an appropriate WritableRaster is created.

Specified by:

copyData in interface RenderedImage

Parameters:

outRaster - a WritableRaster to hold the returned part of the image, or null

Returns:

a reference to the supplied or created WritableRaster.

setData

public void setData(Raster r)

Sets a rectangular region of the image to the contents of the specified Raster r, which is assumed to be in the same coordinate space as the BufferedImage. The operation is clipped to the bounds of the BufferedImage.

Specified by:

setData in interface WritableRenderedImage

Parameters:

r - the specified Raster

See Also:

• getData()
• getData(Rectangle)

addTileObserver

public void addTileObserver(TileObserver to)

Adds a tile observer. If the observer is already present, it receives multiple notifications.

This method ignores its parameters and does nothing, since BufferedImage is always checked out for writing and cannot be made read-only, so there can never be events to dispatch.

Specified by:

addTileObserver in interface WritableRenderedImage

Parameters:

to - the specified TileObserver

removeTileObserver

public void removeTileObserver(TileObserver to)

Removes a tile observer. If the observer was not registered, nothing happens. If the observer was registered for multiple notifications, it is now registered for one fewer notification.

This method ignores the given observer, since addTileObserver(TileObserver) adds none.

Specified by:

removeTileObserver in interface WritableRenderedImage

Parameters:

to - the specified TileObserver.

isTileWritable

public boolean isTileWritable(int tileX,
 int tileY)

Returns whether or not a tile is currently checked out for writing. The only tile in a BufferedImage is at (0,0) and it is always writable, so calling this method with (0,0) will always return true, and any other coordinate will cause an exception to be thrown.

Specified by:

isTileWritable in interface WritableRenderedImage

Parameters:

tileX - the x index of the tile.

tileY - the y index of the tile.

Returns:

true if the tile specified by the specified indices is checked out for writing; false otherwise.

Throws:

IllegalArgumentException - if either tileX or tileY is not equal to 0

getWritableTileIndices

public Point[] getWritableTileIndices()

Returns an array of Point objects indicating which tiles are checked out for writing. Returns null if none are checked out.

Since a BufferedImage consists of a single tile, and that tile is always checked out for writing, this method returns an array of one point. Further, the offset shall be consistent with getMinTileX() and getMinTileY(), which are always (0,0) in BufferedImage. That will always be the coordinates of the single returned Point.

Specified by:

getWritableTileIndices in interface WritableRenderedImage

Returns:

a Point array that indicates the tiles that are checked out for writing, or null if no tiles are checked out for writing.

hasTileWriters

public boolean hasTileWriters()

Returns whether or not any tile is checked out for writing. Semantically equivalent to

 (getWritableTileIndices() != null).
 

Specified by:

hasTileWriters in interface WritableRenderedImage

Returns:

true if any tile is checked out for writing; false otherwise.

getWritableTile

public WritableRaster getWritableTile(int tileX,
 int tileY)

Checks out a tile for writing. All registered TileObservers are notified when a tile goes from having no writers to having one writer.

This method unconditionally returns the single tile without checking the passed values. No listeners are notified since the returned tile is always checked out for writing.

Specified by:

getWritableTile in interface WritableRenderedImage

Parameters:

tileX - the x index of the tile

tileY - the y index of the tile

Returns:

a WritableRaster that is the tile, indicated by the specified indices, to be checked out for writing.

releaseWritableTile

public void releaseWritableTile(int tileX,
 int tileY)

Relinquishes permission to write to a tile. If the caller continues to write to the tile, the results are undefined. Calls to this method should only appear in matching pairs with calls to getWritableTile(int, int). Any other leads to undefined results. All registered TileObservers are notified when a tile goes from having one writer to having no writers.

This method immediately returns without checking the passed values. No listeners are notified since the single tile is always checked out for writing.

Specified by:

releaseWritableTile in interface WritableRenderedImage

Parameters:

tileX - the x index of the tile

tileY - the y index of the tile

getTransparency

public int getTransparency()

Returns the transparency. Returns either OPAQUE, BITMASK, or TRANSLUCENT.

Specified by:

getTransparency in interface Transparency

Returns:

the transparency of this BufferedImage.

Since:

1.5

See Also:

• Transparency.OPAQUE
• Transparency.BITMASK
• Transparency.TRANSLUCENT