astro.fits

Class Arithmetics

java.lang.Object

astro.fits.Arithmetics

public class Arithmetics
extends Object

Collection of image arithmetics.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	Arithmetics.Convolve We convolve the image on the first command line argument with increasing kernel size.
static class	Arithmetics.Op

Constructor Summary

Constructors

Constructor and Description
Arithmetics()

Method Summary

Modifier and Type	Method and Description
static MImageHDU	between(MImageHDU a1, MImageHDU a2, double w) Returns balanced data in between two Image HDU such that the weight factor is applied to the first data and (1-weight) is applied to the second data and the sum is returned.
static float[]	convolve(float[] adu, ArrayLayout ladu, float[] kernel, ArrayLayout lkernel) Convolves image data with a float matrix.
static float[]	convolve(float[] adu, ArrayLayout ladu, float[] kernel, ArrayLayout lkernel, int edge) Convolves image data with a float matrix.
static List<MImageHDU>	equalSize(List<MImageHDU> all) Takes a list of image hdu and returns only those that have data and match the first HDU in size.
static List<MImageHDU>	equalSize(List<MImageHDU> all, ArrayLayout size) Takes a list of image hdu and returns only those that have data of the specified size.
static float[]	getEqualWeightKernel(int xhalf, int yhalf) Returns a kernel that is normalized to 1, with all matrix elements identical value.

Methods inherited from class java.lang.Object

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

Constructor Detail

Arithmetics

public Arithmetics()

Method Detail

equalSize

public static List<MImageHDU> equalSize(List<MImageHDU> all)

Takes a list of image hdu and returns only those that have data and match the first HDU in size.

Parameters:

all -

size - If null, first image HDU is used for size.

Returns:

equalSize

public static List<MImageHDU> equalSize(List<MImageHDU> all,
                                        ArrayLayout size)

Takes a list of image hdu and returns only those that have data of the specified size.

Parameters:

all -

size - May not be null

Returns:

between

public static final MImageHDU between(MImageHDU a1,
                                      MImageHDU a2,
                                      double w)
                               throws BasicFitsException

Returns balanced data in between two Image HDU such that the weight factor is applied to the first data and (1-weight) is applied to the second data and the sum is returned. Useful for estimating calibration data from dusk and dawn to the center of the night. Return data is always float.

Throws:

BasicFitsException

convolve

public static float[] convolve(float[] adu,
                               ArrayLayout ladu,
                               float[] kernel,
                               ArrayLayout lkernel)
                        throws BasicFitsException

Convolves image data with a float matrix. The image and the kernel are provided as one-dimensional arrays with specified layouts. The returned image is of equal layout as the original

Parameters:

adu - The image data as a float array

ladu - The geometry of the image

kernel - The kernel as a float array

lkernel - The geometry of the kernel

Returns:

The convolved image as a float array, same geometry as original.

Throws:

BasicFitsException

convolve

public static float[] convolve(float[] adu,
                               ArrayLayout ladu,
                               float[] kernel,
                               ArrayLayout lkernel,
                               int edge)
                        throws BasicFitsException

Convolves image data with a float matrix. The image and the kernel are provided as one-dimensional arrays with specified layouts. The returned image is of equal layout as the original

Parameters:

adu - The image data as a float array

ladu - The geometry of the image

kernel - The kernel as a float array

lkernel - The geometry of the kernel

edge - Treatment of edge pixel: Zero or original (0/1)

Returns:

The convolved image as a float array, same geometry as original.

Throws:

BasicFitsException

getEqualWeightKernel

public static float[] getEqualWeightKernel(int xhalf,
                                           int yhalf)

Returns a kernel that is normalized to 1, with all matrix elements identical value.

Parameters:

xhalf - Half-size of the kernel in x

yhalf - Half-size of the kernel in y

Returns:

A (2x+1)x(2y+1) array