net.imglib2.algorithm.blocks.downsample

Class Downsample

java.lang.Object

net.imglib2.algorithm.blocks.downsample.Downsample

public class Downsample
extends Object

Downsampling by factor 2. Coordinates of downsampled pixel: either centered, or shifted by half a pixel.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	Downsample.ComputationType Specify in which precision should intermediate values be computed.
static class	Downsample.Offset Specify where downsampled pixels should be placed.

Constructor Summary

Constructors

Constructor and Description
Downsample()

Method Summary

Modifier and Type	Method and Description
static <T extends NativeType<T>> UnaryBlockOperator<T,T>	downsample(T type, Downsample.ComputationType computationType, Downsample.Offset offset, boolean[] downsampleInDim) Create a UnaryBlockOperator to downsample (by factor 2) blocks of the standard ImgLib2 RealType.
static <T extends NativeType<T>> UnaryBlockOperator<T,T>	downsample(T type, Downsample.ComputationType computationType, Downsample.Offset offset, int numDimensions) Create a UnaryBlockOperator to downsample (by factor 2, in all dimensions) blocks of the standard ImgLib2 RealType.
static <T extends NativeType<T>> UnaryBlockOperator<T,T>	downsample(T type, Downsample.Offset offset, int numDimensions) Create a UnaryBlockOperator to downsample (by factor 2, in all dimensions) blocks of the standard ImgLib2 RealType.
static <T extends NativeType<T>> UnaryBlockOperator<T,T>	downsample(T type, int numDimensions) Create a UnaryBlockOperator to downsample (by factor 2, in all dimensions) blocks of the standard ImgLib2 RealType.
static long[]	getDownsampledDimensions(long[] imgDimensions, boolean[] downsampleInDim) Returns recommended size of the downsampled image, given an input image of size imgDimensions.

Methods inherited from class java.lang.Object

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

Constructor Detail

Downsample

public Downsample()

Method Detail

getDownsampledDimensions

public static long[] getDownsampledDimensions(long[] imgDimensions,
                                              boolean[] downsampleInDim)

Returns recommended size of the downsampled image, given an input image of size imgDimensions. In each dimension (that should be downsampled), the recommended size is input size / 2, rounding up (e.g., a 5 pixel input image should be downsampled to a 3 pixel image).

Parameters:

imgDimensions - dimensions of the input image

downsampleInDim - for each dimension (same length as imgDimensions}: true if the input image should be down

Returns:

downsample

public static <T extends NativeType<T>> UnaryBlockOperator<T,T> downsample(T type,
                                                                           Downsample.ComputationType computationType,
                                                                           Downsample.Offset offset,
                                                                           boolean[] downsampleInDim)

Create a UnaryBlockOperator to downsample (by factor 2) blocks of the standard ImgLib2 RealType. The downsampleInDim argument spwecifies in which dimensions the input should be downsampled.

Supported types are UnsignedByteType, UnsignedShortType, UnsignedIntType, ByteType, ShortType, IntType, LongType, FloatType, DoubleType).

Type Parameters:

T - the input/output type

Parameters:

type - instance of the input type

computationType - specifies in which precision intermediate values should be computed. For AUTO, the type that can represent the input/output type without loss of precision is picked. That is, FLOAT for u8, i8, u16, i16, i32, f32, and otherwise DOUBLE for u32, i64, f64.

offset - Specifies where downsampled pixels should be placed. HALF_PIXEL means that each downsampled pixel is computed as the average of 2 neighboring pixels (respectively 4 pixels for 2D, 8 voxels for 3D, etc), and downsampled pixels are shifted by half a pixel. CENTERED means that each downsampled pixel is computed as the weighted average (with weights {.25, .5, .25}) of 3 neighboring pixels (respectively 9 pixels for 2D, 27 voxels for 3D, etc). Downsampled pixels are centered on input pixels.

downsampleInDim - for each dimension d: if downsampleInDim[d]==true if the input image should be downsampled in dimension d.

Returns:

UnaryBlockOperator to downsample blocks of type T

downsample

public static <T extends NativeType<T>> UnaryBlockOperator<T,T> downsample(T type,
                                                                           Downsample.ComputationType computationType,
                                                                           Downsample.Offset offset,
                                                                           int numDimensions)

Create a UnaryBlockOperator to downsample (by factor 2, in all dimensions) blocks of the standard ImgLib2 RealType.

Supported types are UnsignedByteType, UnsignedShortType, UnsignedIntType, ByteType, ShortType, IntType, LongType, FloatType, DoubleType).

Type Parameters:

T - the input/output type

Parameters:

type - instance of the input type

computationType - specifies in which precision intermediate values should be computed. For AUTO, the type that can represent the input/output type without loss of precision is picked. That is, FLOAT for u8, i8, u16, i16, i32, f32, and otherwise DOUBLE for u32, i64, f64.

offset - Specifies where downsampled pixels should be placed. HALF_PIXEL means that each downsampled pixel is computed as the average of 2 neighboring pixels (respectively 4 pixels for 2D, 8 voxels for 3D, etc), and downsampled pixels are shifted by half a pixel. CENTERED means that each downsampled pixel is computed as the weighted average (with weights {.25, .5, .25}) of 3 neighboring pixels (respectively 9 pixels for 2D, 27 voxels for 3D, etc). Downsampled pixels are centered on input pixels.

numDimensions - number of dimensions in input/output image.

Returns:

UnaryBlockOperator to downsample blocks of type T

downsample

public static <T extends NativeType<T>> UnaryBlockOperator<T,T> downsample(T type,
                                                                           Downsample.Offset offset,
                                                                           int numDimensions)

Create a UnaryBlockOperator to downsample (by factor 2, in all dimensions) blocks of the standard ImgLib2 RealType.

Supported types are UnsignedByteType, UnsignedShortType, UnsignedIntType, ByteType, ShortType, IntType, LongType, FloatType, DoubleType).

Precision for intermediate values is chosen as to represent the input/output type without loss of precision is picked. That is, FLOAT for u8, i8, u16, i16, i32, f32, and otherwise DOUBLE for u32, i64, f64.

Type Parameters:

T - the input/output type

Parameters:

type - instance of the input type

offset - Specifies where downsampled pixels should be placed. HALF_PIXEL means that each downsampled pixel is computed as the average of 2 neighboring pixels (respectively 4 pixels for 2D, 8 voxels for 3D, etc), and downsampled pixels are shifted by half a pixel. CENTERED means that each downsampled pixel is computed as the weighted average (with weights {.25, .5, .25}) of 3 neighboring pixels (respectively 9 pixels for 2D, 27 voxels for 3D, etc). Downsampled pixels are centered on input pixels.

numDimensions - number of dimensions in input/output image.

Returns:

UnaryBlockOperator to downsample blocks of type T

downsample

public static <T extends NativeType<T>> UnaryBlockOperator<T,T> downsample(T type,
                                                                           int numDimensions)

Create a UnaryBlockOperator to downsample (by factor 2, in all dimensions) blocks of the standard ImgLib2 RealType.

Supported types are UnsignedByteType, UnsignedShortType, UnsignedIntType, ByteType, ShortType, IntType, LongType, FloatType, DoubleType).

Precision for intermediate values is chosen as to represent the input/output type without loss of precision is picked. That is, FLOAT for u8, i8, u16, i16, i32, f32, and otherwise DOUBLE for u32, i64, f64.

Downsampled pixels are computed as the average of 2 neighboring pixels (respectively 4 pixels for 2D, 8 voxels for 3D, etc). This means downsampled pixels are shifted by half a pixel.

Type Parameters:

T - the input/output type

Parameters:

type - instance of the input type

numDimensions - number of dimensions in input/output image.

Returns:

UnaryBlockOperator to downsample blocks of type T