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I don't think interpolation should be part of the base image class.
Many methods don't need interpolation.
Shouldn't these be part of a derived class? Otherwise, anytime anyone wants to
add a new type of interpolation, they have to modify our base image class.
Also, this adds to the complexity of an already complex class.
s
Paul Hughett wrote:
> Here is a proposed interface for adding pixel interpolation methods
> (and some related methods) to the Image class. Comments are welcome.
>
> Paul Hughett
>
> /**
> * Interpolation method
> *
> * The possible values of this enum select among different methods for
> * interpolating the value of an image at points between those defined.
> * NearestNeighbor takes the value at the defined pixel nearest the
> * desired point. Linear interpolates linearly between the nearest
> * neighbors along each coordinate axis, using a total of 2^N
> * neighboring pixels (where N is the number of dimensions).
> * CubicSpline uses a cubic spline interpolation along each axes, using
> * a total of 4^N * neighboring pixels.
> */
>
> enum InterpolationType {NearestNeighbor, Linear, CubicSpline};
>
> /**
> * Interpolate pixel value at random point
> *
> * This method interpolates to estimate the pixel value at points between
> * the sample points of the image, using a given interpolation method.
> * If the given point is near or outside the RequestedRegion of the image,
> * the missing points are assumed to have the value given by pad; in effect,
> * the RequestedRegion of the image is treated as if it were embedded in
> * an infinite image of pad values. By default, the point is assumed to
> * be in the physical coordinates defined by the Origin and Spacing attributes
> * of the Image. If useindex is set to true, then index coordinates are used
> * instead; this may improve efficiency if many points are computed using
> * some transformation that can be composed with the physical-to-index
> * transformation.
> */
>
> PixelType
> Image::
> InterpolatePixel(
> const Point<VImageDimension,double> &point,
> const InterpolationType type,
> const PixelType &pad = 0,
> const bool useindex = 0) const;
>
> /**
> * Get pixel value or default
> *
> * If the given index is inside the RequestedRegion, return the value
> * of the pixel at that index; otherwise return the default value.
> * This method may be useful in algorithms that can treat an image
> * as embedded in a infinite image of some default value; for example,
> * convolution and resampling algorithms would use a default of zero.
> * (Note that morphological operators might want a non-zero default.)
> */
>
> PixelType
> Image::
> GetPixelOrDefault(
> const IndexType &index,
> const PixelType &default) const;
>
> /**
> * Return physical-to-index transform
> *
> * This method returns the AffineTransform which defines the transformation
> * from physical to index coordinates for this Image.
> */
>
> AffineTransform<double, VImageDimension>
> Image::
> GetPhysicalToIndexTransform() const;
>
> /**
> * Return index-to-physical transform
> *
> * This method returns the AffineTransform which defines the transformation
> * from index to physical coordinates for this Image.
> */
>
> AffineTransform<double, VImageDimension>
> Image::
> GetIndexToPhysicalTransform() const;
>
> _______________________________________________
> Insight-developers mailing list
> Insight-developers@public.kitware.com
> http://public.kitware.com/mailman/listinfo/insight-developers
--
===============================================
Stephen R. Aylward, Ph.D.
Assistant Professor of Radiology
Adjunct Assistant Professor of Computer Science
http://www.cs.unc.edu/~aylward
aylward@unc.edu
(919)966-9695
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I don't think interpolation should be part of the base image class.
Many methods don't need interpolation.
Shouldn't these be part of a derived class? Otherwise, anytime
anyone wants to add a new type of interpolation, they have to modify our
base image class. Also, this adds to the complexity of an already
complex class.
s
Paul Hughett wrote:
Here is a proposed interface for adding pixel interpolation
methods
(and some related methods) to the Image class. Comments are welcome.
Paul Hughett
/**
* Interpolation method
*
* The possible values of this enum select among different methods
for
* interpolating the value of an image at points between those
defined.
* NearestNeighbor takes the value at the defined pixel nearest
the
* desired point. Linear interpolates linearly between the
nearest
* neighbors along each coordinate axis, using a total of 2^N
* neighboring pixels (where N is the number of dimensions).
* CubicSpline uses a cubic spline interpolation along each axes,
using
* a total of 4^N * neighboring pixels.
*/
enum InterpolationType {NearestNeighbor, Linear, CubicSpline};
/**
* Interpolate pixel value at random point
*
* This method interpolates to estimate the pixel value at points
between
* the sample points of the image, using a given interpolation
method.
* If the given point is near or outside the RequestedRegion of
the image,
* the missing points are assumed to have the value given by pad;
in effect,
* the RequestedRegion of the image is treated as if it were embedded
in
* an infinite image of pad values. By default, the point
is assumed to
* be in the physical coordinates defined by the Origin and Spacing
attributes
* of the Image. If useindex is set to true, then index
coordinates are used
* instead; this may improve efficiency if many points are computed
using
* some transformation that can be composed with the physical-to-index
* transformation.
*/
PixelType
Image::
InterpolatePixel(
const Point<VImageDimension,double> &point,
const InterpolationType type,
const PixelType &pad = 0,
const bool useindex = 0) const;
/**
* Get pixel value or default
*
* If the given index is inside the RequestedRegion, return the
value
* of the pixel at that index; otherwise return the default value.
* This method may be useful in algorithms that can treat an image
* as embedded in a infinite image of some default value; for
example,
* convolution and resampling algorithms would use a default of
zero.
* (Note that morphological operators might want a non-zero default.)
*/
PixelType
Image::
GetPixelOrDefault(
const IndexType &index,
const PixelType &default) const;
/**
* Return physical-to-index transform
*
* This method returns the AffineTransform which defines the transformation
* from physical to index coordinates for this Image.
*/
AffineTransform<double, VImageDimension>
Image::
GetPhysicalToIndexTransform() const;
/**
* Return index-to-physical transform
*
* This method returns the AffineTransform which defines the transformation
* from index to physical coordinates for this Image.
*/
AffineTransform<double, VImageDimension>
Image::
GetIndexToPhysicalTransform() const;
_______________________________________________
Insight-developers mailing list
Insight-developers@public.kitware.com
http://public.kitware.com/mailman/listinfo/insight-developers
--
===============================================
Stephen R. Aylward, Ph.D.
Assistant Professor of Radiology
Adjunct Assistant Professor of Computer Science
http://www.cs.unc.edu/~aylward
aylward@unc.edu
(919)966-9695