java.lang.Object | |||
↳ | java.awt.image.ImageFilter | ||
↳ | java.awt.image.ReplicateScaleFilter | ||
↳ | java.awt.image.AreaAveragingScaleFilter |
An ImageFilter class for scaling images using a simple area averaging algorithm that produces smoother results than the nearest neighbor 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 blended to produce pixels for an image of the specified size. The blending process is analogous to scaling up the source image to a multiple of the destination size using pixel replication and then scaling it back down to the destination size by simply averaging all the pixels in the supersized image that fall within a given pixel of the destination image. If the data from the source is not delivered in TopDownLeftRight order then the filter will back off to a simple pixel replication behavior and utilize the requestTopDownLeftRightResend() method to refilter the pixels in a better way at the end.
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.
[Expand]
Inherited Constants | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|
From interface
java.awt.image.ImageConsumer
|
[Expand]
Inherited Fields | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|
From class
java.awt.image.ReplicateScaleFilter
| |||||||||||
From class
java.awt.image.ImageFilter
|
Public Constructors | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|
Constructs an AreaAveragingScaleFilter that scales the pixels from
its source Image as specified by the width and height parameters.
|
Public Methods | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|
Detect if the data is being delivered with the necessary hints
to allow the averaging algorithm to do its work.
| |||||||||||
Combine the components for the delivered int pixels into the
accumulation arrays and send on any averaged data for rows of
pixels that are complete.
| |||||||||||
Combine the components for the delivered byte pixels into the
accumulation arrays and send on any averaged data for rows of
pixels that are complete.
|
[Expand]
Inherited Methods | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|
From class
java.awt.image.ReplicateScaleFilter
| |||||||||||
From class
java.awt.image.ImageFilter
| |||||||||||
From class
java.lang.Object
| |||||||||||
From interface
java.awt.image.ImageConsumer
|
Constructs an AreaAveragingScaleFilter that scales the pixels from its source Image as specified by the width and height parameters.
width | the target width to scale the image |
---|---|
height | the target height to scale the image |
Detect if the data is being delivered with the necessary hints to allow the averaging algorithm to do its work.
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.
hints | a set of hints that the ImageConsumer uses to process the pixels |
---|
Combine the components for the delivered int pixels into the accumulation arrays and send on any averaged data for rows of pixels that are complete. If the correct hints were not specified in the setHints call then relay the work to our superclass which is capable of scaling pixels regardless of the delivery hints.
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.
x | the X coordinate of the upper-left corner of the area of pixels to be set |
---|---|
y | the Y coordinate of the upper-left corner of the area of pixels to be set |
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 |
Combine the components for the delivered byte pixels into the accumulation arrays and send on any averaged data for rows of pixels that are complete. If the correct hints were not specified in the setHints call then relay the work to our superclass which is capable of scaling pixels regardless of the delivery hints.
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.
x | the X coordinate of the upper-left corner of the area of pixels to be set |
---|---|
y | the Y coordinate of the upper-left corner of the area of pixels to be set |
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 |