java.awt.image

Class ReplicateScaleFilter

java.lang.Object

java.awt.image.ImageFilter

java.awt.image.ReplicateScaleFilter

All Implemented Interfaces:

ImageConsumer, Cloneable

Direct Known Subclasses:

AreaAveragingScaleFilter

public class ReplicateScaleFilter
extends ImageFilter

An ImageFilter class for scaling images using the simplest algorithm. This class extends the basic ImageFilter Class to scale an existing image and provide a source for a new image containing the resampled image. The pixels in the source image are sampled to produce pixels for an image of the specified size by replicating rows and columns of pixels to scale up or omitting rows and columns of pixels to scale down.

It is meant to be used in conjunction with a FilteredImageSource object to produce scaled versions of existing images. Due to implementation dependencies, there may be differences in pixel values of an image filtered on different platforms.

Version:

1.16 01/23/03

Author:

Jim Graham

See Also:

FilteredImageSource, ImageFilter

Field Summary

Fields

Modifier and Type	Field and Description
protected int	destHeight The target height to scale the image.
protected int	destWidth The target width to scale the image.
protected Object	outpixbuf A byte array initialized with a size of destWidth and used to deliver a row of pixel data to the ImageConsumer.
protected int[]	srccols An int array containing information about a column of pixels.
protected int	srcHeight The height of the source image.
protected int[]	srcrows An int array containing information about a row of pixels.
protected int	srcWidth The width of the source image.

Fields inherited from class java.awt.image.ImageFilter

consumer

Fields inherited from interface java.awt.image.ImageConsumer

COMPLETESCANLINES, IMAGEABORTED, IMAGEERROR, RANDOMPIXELORDER, SINGLEFRAME, SINGLEFRAMEDONE, SINGLEPASS, STATICIMAGEDONE, TOPDOWNLEFTRIGHT

Constructor Summary

Constructors

Constructor and Description
ReplicateScaleFilter(int width, int height) Constructs a ReplicateScaleFilter that scales the pixels from its source Image as specified by the width and height parameters.

Method Summary

Methods

Modifier and Type	Method and Description
void	setDimensions(int w, int h) Override the dimensions of the source image and pass the dimensions of the new scaled size to the ImageConsumer.
void	setPixels(int x, int y, int w, int h, ColorModel model, byte[] pixels, int off, int scansize) Choose which rows and columns of the delivered byte pixels are needed for the destination scaled image and pass through just those rows and columns that are needed, replicated as necessary.
void	setPixels(int x, int y, int w, int h, ColorModel model, int[] pixels, int off, int scansize) Choose which rows and columns of the delivered int pixels are needed for the destination scaled image and pass through just those rows and columns that are needed, replicated as necessary.
void	setProperties(Hashtable props) Passes along the properties from the source object after adding a property indicating the scale applied.

Methods inherited from class java.awt.image.ImageFilter

clone, getFilterInstance, imageComplete, resendTopDownLeftRight, setColorModel, setHints

Methods inherited from class java.lang.Object

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

Field Detail

srcWidth

protected int srcWidth

The width of the source image.

srcHeight

protected int srcHeight

The height of the source image.

destWidth

protected int destWidth

The target width to scale the image.

destHeight

protected int destHeight

The target height to scale the image.

srcrows

protected int[] srcrows

An int array containing information about a row of pixels.

srccols

protected int[] srccols

An int array containing information about a column of pixels.

outpixbuf

protected Object outpixbuf

A byte array initialized with a size of destWidth and used to deliver a row of pixel data to the ImageConsumer.

Constructor Detail

ReplicateScaleFilter

public ReplicateScaleFilter(int width,
                    int height)

Constructs a ReplicateScaleFilter that scales the pixels from its source Image as specified by the width and height parameters.

Parameters:

width - the target width to scale the image

height - the target height to scale the image

Throws:

IllegalArgumentException - if width equals zero or height equals zero

Method Detail

setProperties

public void setProperties(Hashtable props)

Passes along the properties from the source object after adding a property indicating the scale applied.

Note: This method is intended to be called by the ImageProducer of the Image whose pixels are being filtered. Developers using this class to filter pixels from an image should avoid calling this method directly since that operation could interfere with the filtering operation.

Specified by:

setProperties in interface ImageConsumer

Overrides:

setProperties in class ImageFilter

Parameters:

props - the list of properties to be associated with this image

setDimensions

public void setDimensions(int w,
                 int h)

Override the dimensions of the source image and pass the dimensions of the new scaled size to the ImageConsumer.

Note: This method is intended to be called by the ImageProducer of the Image whose pixels are being filtered. Developers using this class to filter pixels from an image should avoid calling this method directly since that operation could interfere with the filtering operation.

Specified by:

setDimensions in interface ImageConsumer

Overrides:

setDimensions in class ImageFilter

Parameters:

w - the width of the source image

h - the height of the source image

See Also:

ImageConsumer

setPixels

public void setPixels(int x,
             int y,
             int w,
             int h,
             ColorModel model,
             byte[] pixels,
             int off,
             int scansize)

Choose which rows and columns of the delivered byte pixels are needed for the destination scaled image and pass through just those rows and columns that are needed, replicated as necessary.

Note: This method is intended to be called by the ImageProducer of the Image whose pixels are being filtered. Developers using this class to filter pixels from an image should avoid calling this method directly since that operation could interfere with the filtering operation.

Specified by:

setPixels in interface ImageConsumer

Overrides:

setPixels in class ImageFilter

w - the width of the area of pixels

h - the height of the area of pixels

model - the specified ColorModel

pixels - the array of pixels

off - the offset into the pixels array

scansize - the distance from one row of pixels to the next in the pixels array

See Also:

ImageConsumer.setPixels(int, int, int, int, java.awt.image.ColorModel, byte[], int, int)

setPixels

public void setPixels(int x,
             int y,
             int w,
             int h,
             ColorModel model,
             int[] pixels,
             int off,
             int scansize)

Choose which rows and columns of the delivered int pixels are needed for the destination scaled image and pass through just those rows and columns that are needed, replicated as necessary.

Note: This method is intended to be called by the ImageProducer of the Image whose pixels are being filtered. Developers using this class to filter pixels from an image should avoid calling this method directly since that operation could interfere with the filtering operation.

Specified by:

setPixels in interface ImageConsumer

Overrides:

setPixels in class ImageFilter

w - the width of the area of pixels

h - the height of the area of pixels

model - the specified ColorModel

pixels - the array of pixels

off - the offset into the pixels array

scansize - the distance from one row of pixels to the next in the pixels array

See Also:

ImageConsumer.setPixels(int, int, int, int, java.awt.image.ColorModel, byte[], int, int)