public class ContinuedConvolution extends java.lang.Object implements Convolution
The filter allowing to transform any
Convolution object to another instance of that interface,
which uses some non-trivial form of continuation outside the source matrix.
This object is built on the base of some parent object,
Convolution, and some
This object works almost identically to the parent object with the only exception,
that it uses the specified continuation model instead of the default pseudo-cyclic continuation.
More precisely, all methods of this object call the corresponding methods of the parent one.
But before calling any processing method, the source matrix is appended (outside its bounds)
by some area of additional values
with help of
Matrix.subMatrix(long, long, net.algart.arrays.Matrix.ContinuationMode) method,
continuation mode of this filter.
So, all dimensions of the appended matrix are little greater than the corresponding dimensions
of the source one, and extra elements are (virtually) filled by some values according the given continuation mode.
The size of extension along all coordinates depends on the pattern and the performed operation.
After this, the corresponding method of parent object processes the appended matrix,
and the method of this class returns the corresponding submatrix of the result, with dimensions, equal
to the dimensions of the source matrix.
The processing is little different for the method
convolution(Matrix, Matrix, WeightedPattern),
placing the result into the first argument.
In this case, the destination (updatable) matrix is (virtually) extended like the source matrix
before calculations with help of
Matrix.subMatrix(long, long, net.algart.arrays.Matrix.ContinuationMode) method;
so, the calculated data are correctly stored into the original destination matrix.
The appending along all coordinates is performed in such a way, that the resulting matrix
is the same, as if the source matrix would be virtually appended until the infinity along all directions,
according the selected
Matrix.ContinuationMode.NONE continuation mode cannot be used in this class:
such value of continuationMode argument of the instantiation method
getInstance(Convolution, Matrix.ContinuationMode) leads
Note: in improbable cases, when the dimensions of the source matrix and/or
the sizes of the pattern are extremely large (about 263),
so that the necessary appended matrices should have dimensions or total number of elements,
This class is immutable and thread-safe: there are no ways to modify settings of the created instance.
AlgART Laboratory 2007–2014
|Modifier and Type||Method and Description|
Returns an immutable view of the passed source matrix, such that any reading data from it calculates and returns the convolution of the source matrix by the specified pattern.
Returns the current context used by this instance for all operations.
Switches the context: returns an instance, identical to this one excepting that it uses the specified newContext for all operations.
Returns the continuation mode, used by this object for virtual continuing the source matrix.
Returns a new updatable matrix, containing the convolution of the source matrix by the specified pattern.
Returns new instance of this class with the passed parent
Returns true, if this class works in the default
public static ContinuedConvolution getInstance(Convolution parent, Matrix.ContinuationMode continuationMode)
Convolutionobject and the specified continuation mode. See comments to
Matrix.ContinuationModeclass for more information about possible continuations.
parent- the instance of
Convolutioninterface that will perform all operations.
continuationMode- the mode of continuation outside the source matrix.
java.lang.NullPointerException- if parent or continuationMode argument is null.
java.lang.IllegalArgumentException- if continuationMode==
public Convolution parent()
Convolutionobject, passed to
public Matrix.ContinuationMode continuationMode()
public ArrayContext context()
public Convolution context(ArrayContext newContext)
subtaskof the full task.
public boolean isPseudoCyclic()
pseudo-cyclic continuation mode.
More precisely, it means that when the value in some element of the processed matrix,
returned by a method of this class, depends on elements of the source matrix, lying outside its bounds,
then it is supposed that the values outside the source matrix are calculated as described in
Matrix.ContinuationMode.PSEUDO_CYCLIC. Exactly such behaviour is specified in
the comments to the
method as the default definition of convolution.
This method returns true in
However, it usually returns false in
— excepting the only degenerated case when the used
continuation mode is
public double increment(java.lang.Class<?> elementType)
public Matrix<? extends PArray> asConvolution(Matrix<? extends PArray> src, WeightedPattern pattern)
type(PArray.class), src, pattern). In other words, the element type of the returned matrix is chosen the same as in src matrix.
public <T extends PArray> Matrix<T> asConvolution(java.lang.Class<? extends T> requiredType, Matrix<? extends PArray> src, WeightedPattern pattern)
Convolution.convolution(Class, Matrix, WeightedPattern)method about the "convolution" term.
The matrix, returned by this method, is immutable, and the class of its built-in array
implements one of the basic interfaces
The class of desired interface (one of 8 possible classes) must be passed as requiredType argument.
So, it defines the element type of the returned matrix.
For example, if requiredType=
ByteArray.class, the returned matrix consists of byte
elements. The rules of casting the real numbers, results of the convolution, to the desired element type
are the same as in
Arrays.asFuncArray(boolean, net.algart.math.functions.Func, Class, PArray...)
method with the argument truncateOverflows=true.
The result is usually "lazy", that means that this method finishes immediately and all
actual calculations are performed while getting elements of the returned matrix.
It is true for all implementations provided by this package.
However, some implementations may not support lazy dilation;
then this method will be equivalent to
Convolution.convolution(Class, Matrix, WeightedPattern).
Please note: this method does not require time, but the resulting matrix can work slowly!
for example, reading all its content than work much slower than
Convolution.convolution(Class, Matrix, WeightedPattern) method for some complex patterns.
Usually you should use it only for very little patterns, or if you know that the implementation
of this interface does not provide better algorithm for non-"lazy"
Convolution.convolution(Class, , Matrix, WeightedPattern) method.
public Matrix<? extends UpdatablePArray> convolution(Matrix<? extends PArray> src, WeightedPattern pattern)
Usually convolution means the weighted sum of the set of matrices,
obtained by pseudo-cyclic shifting the source matrix by the vectors,
equal to all pattern points, with weights, equal to
of the pattern points.
More precisely, let mi=
where ip is the point #i from all points contained in the pattern,
and let wi=pattern.
Then the every element of the returned matrix is the weighted sum of all corresponding elements
of all mi matrices:
element typeof the created matrix is the same as the element type of the source one. The byte and short elements are considered to be unsigned. If the element type if integer, the precise is rounded to the nearest integer.
BasicConvolution class strictly complies this definition.
However, other implementations of this interface may use alternate definitions of the convolution term.
For example, elements outside the matrix may be supposed to be filled according some non-trivial rules
instead of pseudo-cyclic continuation
or only some region of the matrix may be processed, etc.
src- the source matrix.
pattern- the pattern.
Convolution.asConvolution(Class, Matrix, WeightedPattern)
public <T extends PArray> Matrix<? extends T> convolution(java.lang.Class<? extends T> requiredType, Matrix<? extends PArray> src, WeightedPattern pattern)