rave_transform.c File Reference

Transformation routines for going between projections. More...

#include "rave_transform.h"
#include "raveutil.h"
#include "limits.h"
#include "float.h"
#include "rave_alloc.h"
#include "rave_debug.h"
#include <math.h>
#include <stdio.h>
#include "projection.h"

Functions
double	get_array_item_2d (unsigned char *in_a, int x, int y, RaveDataType type, int stride_xsize)
	Gets the value at position x,y from the data field.
void	set_array_item_2d (unsigned char *out_a, int x, int y, double v, RaveDataType type, int stride_xsize)
	Sets the value at position x,y in the data field.
double	get_array_item_3d (RavePolarVolume *pvol, int e, int r, int a)
	Gets a value from a polar volume.
void	set_array_item_3d (RavePolarVolume *pvol, int e, int r, int a, double v)
	Sets a value in a polar volume.
TransformWeight *	init_tw (int noi)
	Creates a TransformWeight struct with noi number of weights allocated.
void	free_tw (TransformWeight *v)
	Deallocates the whole TransformWeight struct v, including the weights allocated.
TransformWeight *	get_nearest_weights_2d (int x, int y, UV here_s, RaveTransform2D *tw)
	Gets the weight for the pixel closest to here_s and .
TransformWeight *	get_bilinear_weights_2d (int x, int y, UV here_s, RaveTransform2D *tw)
	Gets the bilinear weights for the pixel surrounding here_s.
TransformWeight *	get_cubic_weights_2d (int x, int y, UV here_s, RaveTransform2D *tw)
	Gets the cubic weights for the pixel surrounding here_s.
TransformWeight *	get_cressman_weights_2d (int x, int y, UV here_s, RaveTransform2D *tw)
	Gets the cressman weights for the pixel surrounding here_s.
TransformWeight *	get_weights_2d (int x, int y, UV here_s, RaveTransform2D *tw)
	Gets the appropriate weights for the current algorithm and position.
double	compute_weights_2d (TransformWeight *tw)
	Evaluates the weights specified in the TransformWeight struct, the weights will be normalized within the function by dividing the given weight with the total_wsum attribute in the TransformWeight struct.

Detailed Description

Transformation routines for going between projections.

Author

Anders Henja (Swedish Meteorological and Hydrological Institute, SMHI)

Date

2009-08-05

Function Documentation

compute_weights_2d()

double compute_weights_2d

(

TransformWeight *

tw

)

Evaluates the weights specified in the TransformWeight struct, the weights will be normalized within the function by dividing the given weight with the total_wsum attribute in the TransformWeight struct.

Parameters

[in]

tw

the transformation weight(s)

Returns

the computed value

free_tw()

void free_tw

(

TransformWeight *

v

)

Deallocates the whole TransformWeight struct v, including the weights allocated.

Parameters

[in]

v

the structure to be deallocated

get_array_item_2d()

double get_array_item_2d	(	unsigned char *	data,
		int	x,
		int	y,
		RaveDataType	type,
		int	stride_xsize )

Gets the value at position x,y from the data field.

Parameters

[in]	data	the data array
[in]	x	the x position
[in]	y	the y position
[in]	type	the type of the data
[in]	stride_xsize	the stride

get_array_item_3d()

double get_array_item_3d	(	RavePolarVolume *	pvol,
		int	e,
		int	r,
		int	a )

Gets a value from a polar volume.

Parameters

[in]	pvol	the polar volume
[in]	e	the elevation
[in]	r	the range bin
[in]	a	the azimuth

Returns

the value at the specified position

get_bilinear_weights_2d()

TransformWeight * get_bilinear_weights_2d	(	int	x,
		int	y,
		UV	here_s,
		RaveTransform2D *	tw )

Gets the bilinear weights for the pixel surrounding here_s.

Parameters

[in]	x	position in the out projection (only used for debugging)
[in]	y	position in the out projection (only used for debugging)
[in]	here_s	the pixel
[in]	tw	the transformation structure

Returns

the weight(s)

get_cressman_weights_2d()

TransformWeight * get_cressman_weights_2d	(	int	x,
		int	y,
		UV	here_s,
		RaveTransform2D *	tw )

Gets the cressman weights for the pixel surrounding here_s.

Parameters

[in]	x	position in the out projection (only used for debugging)
[in]	y	position in the out projection (only used for debugging)
[in]	here_s	the pixel
[in]	tw	the transformation structure

Returns

the weight(s)

get_cubic_weights_2d()

TransformWeight * get_cubic_weights_2d	(	int	x,
		int	y,
		UV	here_s,
		RaveTransform2D *	tw )

Gets the cubic weights for the pixel surrounding here_s.

Parameters

[in]	x	position in the out projection (only used for debugging)
[in]	y	position in the out projection (only used for debugging)
[in]	here_s	the pixel
[in]	tw	the transformation structure

Returns

the weight(s)

get_nearest_weights_2d()

TransformWeight * get_nearest_weights_2d	(	int	x,
		int	y,
		UV	here_s,
		RaveTransform2D *	tw )

Gets the weight for the pixel closest to here_s and .

Parameters

[in]	x	position in the out projection (only used for debugging)
[in]	y	position in the out projection (only used for debugging)
[in]	here_s	the pixel
[in]	tw	the transformation structure

Returns

the weight(s)

get_weights_2d()

TransformWeight * get_weights_2d	(	int	x,
		int	y,
		UV	here_s,
		RaveTransform2D *	tw )

Gets the appropriate weights for the current algorithm and position.

Parameters

[in]	x	position in the out projection (only used for debugging)
[in]	y	position in the out projection (only used for debugging)
[in]	here_s	the pixel
[in]	tw	the transformation structure.

Returns

the weight(s)

init_tw()

TransformWeight * init_tw

(

int

noi

)

Creates a TransformWeight struct with noi number of weights allocated.

Parameters

[in]

noi

the number of weights to be allocated

Returns

a TransformWeight struct with an array of weights allocated

set_array_item_2d()

void set_array_item_2d	(	unsigned char *	data,
		int	x,
		int	y,
		double	v,
		RaveDataType	type,
		int	stride_xsize )

Sets the value at position x,y in the data field.

Parameters

[in]	data	the data array
[in]	x	the x position
[in]	y	the y position
[in]	v	the value that will be converted into the specified type
[in]	type	the type of the data
[in]	stride_xsize	the stride

set_array_item_3d()

void set_array_item_3d	(	RavePolarVolume *	pvol,
		int	e,
		int	r,
		int	a,
		double	v )

Sets a value in a polar volume.

Parameters

[in]	pvol	the polar volume
[in]	e	the elevation
[in]	r	the range bin
[in]	a	the azimuth
[in]	v	the value to be set