Bilinear interpolation functions for 2D images. More...

#include <vcl_cassert.h>
#include <vcl_cstddef.h>
#include <vil/vil_image_view.h>
#include <vil/vil_na.h>

Functions
template<class T >
double	vil_bilin_interp_unsafe (double x, double y, const T *data, vcl_ptrdiff_t xstep, vcl_ptrdiff_t ystep)
	Compute bilinear interpolation at (x,y), no bound checks. Requires 0<x<ni-2, 0<y<nj-2.
template<class T >
double	vil_bilin_interp_unsafe (double x, double y, const T *data, int, int, vcl_ptrdiff_t xstep, vcl_ptrdiff_t ystep)
	Compute bilinear interpolation at (x,y), no bound checks. Requires 0<x<ni-2, 0<y<nj-2.
template<class T >
double	vil_bilin_interp_raw (double x, double y, const T *data, vcl_ptrdiff_t xstep, vcl_ptrdiff_t ystep)
	Compute bilinear interpolation at (x,y), no bound checks.
template<class T >
double	vil_bilin_interp_raw (double x, double y, const T *data, int, int, vcl_ptrdiff_t xstep, vcl_ptrdiff_t ystep)
	Compute bilinear interpolation at (x,y), no bound checks.
template<class T >
double	vil_bilin_interp_safe (double x, double y, const T *data, int nx, int ny, vcl_ptrdiff_t xstep, vcl_ptrdiff_t ystep)
	Compute bilinear interpolation at (x,y), with bound checks.
template<class T >
double	vil_bilin_interp_safe_edgena (double x, double y, const T *data, int nx, int ny, vcl_ptrdiff_t xstep, vcl_ptrdiff_t ystep)
	Compute bilinear interpolation at (x,y), with bound checks.
template<class T >
double	vil_bilin_interp_safe (const vil_image_view< T > &view, double x, double y, unsigned p=0)
	Compute bilinear interpolation at (x,y), with bound checks.
template<class T >
double	vil_bilin_interp_safe_edgena (const vil_image_view< T > &view, double x, double y, unsigned p=0)
	Compute bilinear interpolation at (x,y), with bound checks.
template<class T >
double	vil_bilin_interp (double x, double y, const T *data, int nx, int ny, vcl_ptrdiff_t xstep, vcl_ptrdiff_t ystep)
	Compute bilinear interpolation at (x,y), with minimal bound checks.
template<class T >
double	vil_bilin_interp (const vil_image_view< T > &view, double x, double y, unsigned p=0)
	Compute bilinear interpolation at (x,y), with minimal bound checks.
template<class T >
double	vil_bilin_interp_safe_extend (double x, double y, const T *data, int nx, int ny, vcl_ptrdiff_t xstep, vcl_ptrdiff_t ystep)
	Compute bilinear interpolation at (x,y), with bound checks.
template<class T >
double	vil_bilin_interp_safe_extend (const vil_image_view< T > &view, double x, double y, unsigned p=0)
	Compute bilinear interpolation at (x,y), with bound checks.

Detailed Description

Bilinear interpolation functions for 2D images.

Author:: Tim Cootes

The vil bicub source files were derived from the corresponding vil bilin files, thus the vil bilin/bicub source files are very similar. If you modify something in this file, there is a corresponding bicub file that would likely also benefit from the same change.

Definition in file vil_bilin_interp.h.

Function Documentation

template<class T >

double vil_bilin_interp	(	double	x,
		double	y,
		const T *	data,
		int	nx,
		int	ny,
		vcl_ptrdiff_t	xstep,
		vcl_ptrdiff_t	ystep
	)		`[inline]`

Compute bilinear interpolation at (x,y), with minimal bound checks.

Image is nx * ny array of Ts. x,y element is data[ystep*y+xstep*x] If (x,y) is outside interpolatable image region and NDEBUG is not defined the code will fail an ASSERT. The safe interpolatable region is [0,nx-1]*[0,ny-1].

Definition at line 156 of file vil_bilin_interp.h.

template<class T >

double vil_bilin_interp	(	const vil_image_view< T > &	view,
		double	x,
		double	y,
		unsigned	p = `0`
	)		`[inline]`

Compute bilinear interpolation at (x,y), with minimal bound checks.

If (x,y) is outside interpolatable image region and NDEBUG is not defined the code will fail an ASSERT. The safe interpolatable region is [0,view.ni()-1]*[0,view.nj()-1].

Definition at line 173 of file vil_bilin_interp.h.

template<class T >

double vil_bilin_interp_raw	(	double	x,
		double	y,
		const T *	data,
		vcl_ptrdiff_t	xstep,
		vcl_ptrdiff_t	ystep
	)		`[inline]`

Compute bilinear interpolation at (x,y), no bound checks.

Image is nx * ny array of Ts. x,y element is data[xstep*x+ystep*y] No bound checks are done.

Definition at line 58 of file vil_bilin_interp.h.

template<class T >

double vil_bilin_interp_raw	(	double	x,
		double	y,
		const T *	data,
		int	,
		int	,
		vcl_ptrdiff_t	xstep,
		vcl_ptrdiff_t	ystep
	)		`[inline]`

Compute bilinear interpolation at (x,y), no bound checks.

Image is nx * ny array of Ts. x,y element is data[xstep*x+ystep*y] No bound checks are done. This is a version of vil_bilin_interp_raw with the same function signature as vil_bilin_interp_safe.

Definition at line 86 of file vil_bilin_interp.h.

template<class T >

double vil_bilin_interp_safe	(	double	x,
		double	y,
		const T *	data,
		int	nx,
		int	ny,
		vcl_ptrdiff_t	xstep,
		vcl_ptrdiff_t	ystep
	)		`[inline]`