org.esa.beam.framework.dataop.resamp
Interface Resampling

public interface Resampling

An interface used to implement different resampling strategies.

Version:

$Revision$ $Date$

Author:

Norman Fomferra, Norman Fomferra (norman.fomferra@brockmann-consult.de)

Nested Class Summary

static class	Resampling.Index An index is used to provide resampling information at a given raster position x,y.
static interface	Resampling.Raster A raster is a rectangular grid which provides sample values at a given raster position x,y.

Field Summary

static Resampling	BILINEAR_INTERPOLATION The bilinear interpolation resampling method.
static Resampling	CUBIC_CONVOLUTION The cubic convolution resampling method.
static Resampling	NEAREST_NEIGHBOUR The nearest neighbour resampling method.

Method Summary

void	computeIndex(float x, float y, int width, int height, Resampling.Index index) Computes the index's properties for the given pixel coordinate.
Resampling.Index	createIndex() Factory method which creates an appropriate index for raster access.
String	getName() Gets a unique identifier for this resampling method, e.g.
float	resample(Resampling.Raster raster, Resampling.Index index) Performs the actual resampling operation.

Field Detail

NEAREST_NEIGHBOUR

static final Resampling NEAREST_NEIGHBOUR

The nearest neighbour resampling method.

BILINEAR_INTERPOLATION

static final Resampling BILINEAR_INTERPOLATION

The bilinear interpolation resampling method.

CUBIC_CONVOLUTION

static final Resampling CUBIC_CONVOLUTION

The cubic convolution resampling method.

Method Detail

getName

String getName()

Gets a unique identifier for this resampling method, e.g. "BILINEAR_INTERPOLATION".

Returns:

a unique name

createIndex

Resampling.Index createIndex()

Factory method which creates an appropriate index for raster access.

Returns:

an appropriate index, never null

computeIndex

void computeIndex(float x,
                  float y,
                  int width,
                  int height,
                  Resampling.Index index)

Computes the index's properties for the given pixel coordinate.

Parameters:

x - the raster's x coordinate

y - the raster's y coordinate

width - the raster's width

height - the raster's height

index - the index object to which the results are to be assigned

resample

float resample(Resampling.Raster raster,
               Resampling.Index index)
               throws Exception

Performs the actual resampling operation. If a sample value could not be computed at the given index, e.g. in case of missing data, the method returns the special value Float.NaN.

Parameters:

raster - the raster

index - the index, must be computed using the computeIndex(float, float, int, int, org.esa.beam.framework.dataop.resamp.Resampling.Index) method

Returns:

either the re-sampled sample value or Float.NaN.

Throws:

Exception - if a non-runtime error occurs, e.g I/O error