Package org.apache.sis.image

Class PixelIterator.DoubleWindow

java.lang.Object

org.apache.sis.image.PixelIterator.Window<DoubleBuffer>

org.apache.sis.image.PixelIterator.DoubleWindow

Enclosing class:

PixelIterator

private final class PixelIterator.DoubleWindow
extends PixelIterator.Window<DoubleBuffer>

PixelIterator.Window implementation backed by an array of double[]. This is the implementation used by Apache SIS for most computations.

Performance note Java2D has numerous optimizations for the integer cases, with no equivalent for the floating point cases. Consequently, if the data buffer is known to use some integer type, it is faster to get integer values and convert them to double values instead of to request directly floating-point values. However, the improvement is not as much as using BandedIterator as least for small windows. For that reason, we do not provide the "integers converted to doubles" performance workaround for now. Even if we provided it, this DoubleWindow would still be necessary for the general case (non-integer data buffers).

Field Summary

Fields

Modifier and Type	Field	Description
private final double[]	data	Sample values in the window (data) and a temporary array (transfer).
private final double[]	transfer	Sample values in the window (data) and a temporary array (transfer).

Fields inherited from class org.apache.sis.image.PixelIterator.Window

DIRECT, TRANSFER, TRANSFER_FROM_OTHER, values

Constructor Summary

Constructors

Constructor	Description
DoubleWindow(double[] data, double[] transfer)	Creates a new window which will store the sample values in the given data array.

Method Summary

Modifier and Type	Method	Description
(package private) Object	getPixels(Raster raster, int subX, int subY, int subWidth, int subHeight, int mode)	Performs the transfer between the underlying raster and this window.
(package private) final PixelIterator	owner()	Returns the iterator that created this window.
void	update()	Updates this window with the sample values in the region starting at current iterator position.

Methods inherited from class org.apache.sis.image.PixelIterator.Window

getSize

Methods inherited from class java.lang.Object

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

Field Details

data

private final double[] data

Sample values in the window (data) and a temporary array (transfer). Those arrays are overwritten when update() is invoked.

transfer

private final double[] transfer

Sample values in the window (data) and a temporary array (transfer). Those arrays are overwritten when update() is invoked.

Constructor Details

DoubleWindow

DoubleWindow(double[] data,
 double[] transfer)

Creates a new window which will store the sample values in the given data array.

Method Details

owner

final PixelIterator owner()

Returns the iterator that created this window.

Specified by:

owner in class PixelIterator.Window<DoubleBuffer>

getPixels

Object getPixels(Raster raster,
 int subX,
 int subY,
 int subWidth,
 int subHeight,
 int mode)

Performs the transfer between the underlying raster and this window.

Specified by:

getPixels in class PixelIterator.Window<DoubleBuffer>

Parameters:

raster - the raster from which to get the pixel values.

subX - the X coordinate of the upper-left pixel location.

subY - the Y coordinate of the upper-left pixel location.

subWidth - width of the pixel rectangle.

subHeight - height of the pixel rectangle.

mode - one of PixelIterator.Window.DIRECT, PixelIterator.Window.TRANSFER or PixelIterator.Window.TRANSFER_FROM_OTHER.

Returns:

the array in which sample values have been stored.

update

public void update()

Updates this window with the sample values in the region starting at current iterator position. This method assumes that PixelIterator.next() or PixelIterator.moveTo(int,int) has been invoked.

Specified by:

update in class PixelIterator.Window<DoubleBuffer>