gd_interpolation.c File Reference

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>
#include "gd.h"
#include "gdhelpers.h"
#include "gd_intern.h"

Go to the source code of this file.

Data Structures
struct	ContributionType
struct	LineContribType

Macros
#define	MIN3(a, b, c)
#define	MAX3(a, b, c)
#define	gd_itofx(x)
#define	gd_ftofx(x)
#define	gd_dtofx(x)
#define	gd_fxtoi(x)
#define	gd_fxtof(x)
#define	gd_fxtod(x)
#define	gd_mulfx(x, y)
#define	gd_divfx(x, y)
#define	DEFAULT_FILTER_BICUBIC   3.0
#define	DEFAULT_FILTER_BOX   0.5
#define	DEFAULT_FILTER_GENERALIZED_CUBIC   0.5
#define	DEFAULT_FILTER_RADIUS   1.0
#define	DEFAULT_LANCZOS8_RADIUS   8.0
#define	DEFAULT_LANCZOS3_RADIUS   3.0
#define	DEFAULT_HERMITE_RADIUS   1.0
#define	DEFAULT_BOX_RADIUS   0.5
#define	DEFAULT_TRIANGLE_RADIUS   1.0
#define	DEFAULT_BELL_RADIUS   1.5
#define	DEFAULT_CUBICSPLINE_RADIUS   2.0
#define	DEFAULT_MITCHELL_RADIUS   2.0
#define	DEFAULT_COSINE_RADIUS   1.0
#define	DEFAULT_CATMULLROM_RADIUS   2.0
#define	DEFAULT_QUADRATIC_RADIUS   1.5
#define	DEFAULT_QUADRATICBSPLINE_RADIUS   1.5
#define	DEFAULT_CUBICCONVOLUTION_RADIUS   3.0
#define	DEFAULT_GAUSSIAN_RADIUS   1.0
#define	DEFAULT_HANNING_RADIUS   1.0
#define	DEFAULT_HAMMING_RADIUS   1.0
#define	DEFAULT_SINC_RADIUS   1.0
#define	DEFAULT_WELSH_RADIUS   1.0
#define	KM_B   (1.0f/3.0f)
#define	KM_C   (1.0f/3.0f)
#define	KM_P0   (( 6.0f - 2.0f * KM_B ) / 6.0f)
#define	KM_P2   ((-18.0f + 12.0f * KM_B + 6.0f * KM_C) / 6.0f)
#define	KM_P3   (( 12.0f - 9.0f * KM_B - 6.0f * KM_C) / 6.0f)
#define	KM_Q0   (( 8.0f * KM_B + 24.0f * KM_C) / 6.0f)
#define	KM_Q1   ((-12.0f * KM_B - 48.0f * KM_C) / 6.0f)
#define	KM_Q2   (( 6.0f * KM_B + 30.0f * KM_C) / 6.0f)
#define	KM_Q3   (( -1.0f * KM_B - 6.0f * KM_C) / 6.0f)
#define	colorIndex2RGBA(c)
#define	colorIndex2RGBcustomA(c, a)

Typedefs
typedef long	gdFixed
typedef enum GD_RESIZE_FILTER_TYPE	gdResizeFilterType

Enumerations
enum	GD_RESIZE_FILTER_TYPE {   FILTER_DEFAULT = 0 , FILTER_BELL , FILTER_BESSEL , FILTER_BLACKMAN ,   FILTER_BOX , FILTER_BSPLINE , FILTER_CATMULLROM , FILTER_COSINE ,   FILTER_CUBICCONVOLUTION , FILTER_CUBICSPLINE , FILTER_HERMITE , FILTER_LANCZOS3 ,   FILTER_LANCZOS8 , FILTER_MITCHELL , FILTER_QUADRATIC , FILTER_QUADRATICBSPLINE ,   FILTER_TRIANGLE , FILTER_GAUSSIAN , FILTER_HANNING , FILTER_HAMMING ,   FILTER_SINC , FILTER_WELSH , FILTER_CALLBACK = 999 }

Functions
int	getPixelInterpolated (gdImagePtr im, const double x, const double y, const int bgColor)
gdImagePtr	gdImageScaleTwoPass (const gdImagePtr src, const unsigned int src_width, const unsigned int src_height, const unsigned int new_width, const unsigned int new_height)
gdImagePtr	gdImageScaleNearestNeighbour (gdImagePtr im, const unsigned int width, const unsigned int height)
gdImagePtr	gdImageScaleBilinear (gdImagePtr im, const unsigned int new_width, const unsigned int new_height)
gdImagePtr	gdImageScaleBicubicFixed (gdImagePtr src, const unsigned int width, const unsigned int height)
gdImagePtr	gdImageScale (const gdImagePtr src, const unsigned int new_width, const unsigned int new_height)
gdImagePtr	gdImageRotateNearestNeighbour (gdImagePtr src, const float degrees, const int bgColor)
gdImagePtr	gdImageRotateGeneric (gdImagePtr src, const float degrees, const int bgColor)
gdImagePtr	gdImageRotateBilinear (gdImagePtr src, const float degrees, const int bgColor)
gdImagePtr	gdImageRotateBicubicFixed (gdImagePtr src, const float degrees, const int bgColor)
gdImagePtr	gdImageRotateInterpolated (const gdImagePtr src, const float angle, int bgcolor)
void	gdDumpRect (const char *msg, gdRectPtr r)
int	gdTransformAffineGetImage (gdImagePtr *dst, const gdImagePtr src, gdRectPtr src_area, const double affine[6])
int	gdTransformAffineCopy (gdImagePtr dst, int dst_x, int dst_y, const gdImagePtr src, gdRectPtr src_region, const double affine[6])
int	gdTransformAffineBoundingBox (gdRectPtr src, const double affine[6], gdRectPtr bbox)
int	gdImageSetInterpolationMethod (gdImagePtr im, gdInterpolationMethod id)
gdInterpolationMethod	gdImageGetInterpolationMethod (gdImagePtr im)

Macro Definition Documentation

colorIndex2RGBA

#define colorIndex2RGBA

(

c

)

Value:

gdTrueColorAlpha(im->red[(c)], im->green[(c)], im->blue[(c)], im->alpha[(c)])

Definition at line 663 of file gd_interpolation.c.

colorIndex2RGBcustomA

#define colorIndex2RGBcustomA	(		c,
			a )

Value:

gdTrueColorAlpha(im->red[(c)], im->green[(c)], im->blue[(c)], im->alpha[(a)])

Definition at line 664 of file gd_interpolation.c.

DEFAULT_BELL_RADIUS

#define DEFAULT_BELL_RADIUS   1.5

Definition at line 129 of file gd_interpolation.c.

DEFAULT_BOX_RADIUS

#define DEFAULT_BOX_RADIUS   0.5

Definition at line 127 of file gd_interpolation.c.

DEFAULT_CATMULLROM_RADIUS

#define DEFAULT_CATMULLROM_RADIUS   2.0

Definition at line 133 of file gd_interpolation.c.

DEFAULT_COSINE_RADIUS

#define DEFAULT_COSINE_RADIUS   1.0

Definition at line 132 of file gd_interpolation.c.

DEFAULT_CUBICCONVOLUTION_RADIUS

#define DEFAULT_CUBICCONVOLUTION_RADIUS   3.0

Definition at line 136 of file gd_interpolation.c.

DEFAULT_CUBICSPLINE_RADIUS

#define DEFAULT_CUBICSPLINE_RADIUS   2.0

Definition at line 130 of file gd_interpolation.c.

DEFAULT_FILTER_BICUBIC

#define DEFAULT_FILTER_BICUBIC   3.0

Definition at line 120 of file gd_interpolation.c.

DEFAULT_FILTER_BOX

#define DEFAULT_FILTER_BOX   0.5

Definition at line 121 of file gd_interpolation.c.

DEFAULT_FILTER_GENERALIZED_CUBIC

#define DEFAULT_FILTER_GENERALIZED_CUBIC   0.5

Definition at line 122 of file gd_interpolation.c.

DEFAULT_FILTER_RADIUS

#define DEFAULT_FILTER_RADIUS   1.0

Definition at line 123 of file gd_interpolation.c.

DEFAULT_GAUSSIAN_RADIUS

#define DEFAULT_GAUSSIAN_RADIUS   1.0

Definition at line 137 of file gd_interpolation.c.

DEFAULT_HAMMING_RADIUS

#define DEFAULT_HAMMING_RADIUS   1.0

Definition at line 139 of file gd_interpolation.c.

DEFAULT_HANNING_RADIUS

#define DEFAULT_HANNING_RADIUS   1.0

Definition at line 138 of file gd_interpolation.c.

DEFAULT_HERMITE_RADIUS

#define DEFAULT_HERMITE_RADIUS   1.0

Definition at line 126 of file gd_interpolation.c.

DEFAULT_LANCZOS3_RADIUS

#define DEFAULT_LANCZOS3_RADIUS   3.0

Definition at line 125 of file gd_interpolation.c.

DEFAULT_LANCZOS8_RADIUS

#define DEFAULT_LANCZOS8_RADIUS   8.0

Definition at line 124 of file gd_interpolation.c.

DEFAULT_MITCHELL_RADIUS

#define DEFAULT_MITCHELL_RADIUS   2.0

Definition at line 131 of file gd_interpolation.c.

DEFAULT_QUADRATIC_RADIUS

#define DEFAULT_QUADRATIC_RADIUS   1.5

Definition at line 134 of file gd_interpolation.c.

DEFAULT_QUADRATICBSPLINE_RADIUS

#define DEFAULT_QUADRATICBSPLINE_RADIUS   1.5

Definition at line 135 of file gd_interpolation.c.

DEFAULT_SINC_RADIUS

#define DEFAULT_SINC_RADIUS   1.0

Definition at line 140 of file gd_interpolation.c.

DEFAULT_TRIANGLE_RADIUS

#define DEFAULT_TRIANGLE_RADIUS   1.0

Definition at line 128 of file gd_interpolation.c.

DEFAULT_WELSH_RADIUS

#define DEFAULT_WELSH_RADIUS   1.0

Definition at line 141 of file gd_interpolation.c.

gd_divfx

#define gd_divfx	(		x,
			y )

Value:

((long)((unsigned long)(x) << 8) / (y))

Definition at line 104 of file gd_interpolation.c.

gd_dtofx

#define gd_dtofx

(

x

)

Value:

(long)((x) * 256)

Definition at line 89 of file gd_interpolation.c.

gd_ftofx

#define gd_ftofx

(

x

)

Value:

(long)((x) * 256)

Definition at line 86 of file gd_interpolation.c.

gd_fxtod

#define gd_fxtod

(

x

)

Value:

((double)(x) / 256)

Definition at line 98 of file gd_interpolation.c.

gd_fxtof

#define gd_fxtof

(

x

)

Value:

((float)(x) / 256)

Definition at line 95 of file gd_interpolation.c.

gd_fxtoi

#define gd_fxtoi

(

x

)

Value:

((x) >> 8)

Definition at line 92 of file gd_interpolation.c.

gd_itofx

#define gd_itofx

(

x

)

Value:

(long)((unsigned long)(x) << 8)

Definition at line 83 of file gd_interpolation.c.

gd_mulfx

#define gd_mulfx	(		x,
			y )

Value:

(((x) * (y)) >> 8)

Definition at line 101 of file gd_interpolation.c.

KM_B

#define KM_B   (1.0f/3.0f)

KM_C

#define KM_C   (1.0f/3.0f)

KM_P0

#define KM_P0   (( 6.0f - 2.0f * KM_B ) / 6.0f)

KM_P2

#define KM_P2   ((-18.0f + 12.0f * KM_B + 6.0f * KM_C) / 6.0f)

KM_P3

#define KM_P3   (( 12.0f - 9.0f * KM_B - 6.0f * KM_C) / 6.0f)

KM_Q0

#define KM_Q0   (( 8.0f * KM_B + 24.0f * KM_C) / 6.0f)

KM_Q1

#define KM_Q1   ((-12.0f * KM_B - 48.0f * KM_C) / 6.0f)

KM_Q2

#define KM_Q2   (( 6.0f * KM_B + 30.0f * KM_C) / 6.0f)

KM_Q3

#define KM_Q3   (( -1.0f * KM_B - 6.0f * KM_C) / 6.0f)

MAX3

#define MAX3	(		a,
			b,
			c )

Value:

((a)<(b)?(MAX(b,c)):(MAX(a,c)))

Definition at line 77 of file gd_interpolation.c.

MIN3

#define MIN3	(		a,
			b,
			c )

Value:

((a)<(b)?(MIN(a,c)):(MIN(b,c)))

Definition at line 73 of file gd_interpolation.c.

Typedef Documentation

gdFixed

typedef long gdFixed

Definition at line 81 of file gd_interpolation.c.

gdResizeFilterType

typedef enum GD_RESIZE_FILTER_TYPE gdResizeFilterType

Definition at line 170 of file gd_interpolation.c.

Enumeration Type Documentation

GD_RESIZE_FILTER_TYPE

enum GD_RESIZE_FILTER_TYPE

Enumerator
FILTER_DEFAULT
FILTER_BELL
FILTER_BESSEL
FILTER_BLACKMAN
FILTER_BOX
FILTER_BSPLINE
FILTER_CATMULLROM
FILTER_COSINE
FILTER_CUBICCONVOLUTION
FILTER_CUBICSPLINE
FILTER_HERMITE
FILTER_LANCZOS3
FILTER_LANCZOS8
FILTER_MITCHELL
FILTER_QUADRATIC
FILTER_QUADRATICBSPLINE
FILTER_TRIANGLE
FILTER_GAUSSIAN
FILTER_HANNING
FILTER_HAMMING
FILTER_SINC
FILTER_WELSH
FILTER_CALLBACK

Definition at line 143 of file gd_interpolation.c.

Function Documentation

gdDumpRect()

void gdDumpRect	(	const char *	msg,
		gdRectPtr	r )

Definition at line 2214 of file gd_interpolation.c.

gdImageGetInterpolationMethod()

gdInterpolationMethod gdImageGetInterpolationMethod

(

gdImagePtr

im

)

Function: gdImageGetInterpolationMethod

Get the current interpolation method

This is here so that the value can be read via a language or VM with an FFI but no (portable) way to extract the value from the struct.

Parameters: im - The image.

Returns: The current interpolation method.

See also:

• <gdInterpolationMethod>
• <gdImageSetInterpolationMethod>

Definition at line 2563 of file gd_interpolation.c.

gdImageRotateBicubicFixed()

gdImagePtr gdImageRotateBicubicFixed	(	gdImagePtr	src,
		const float	degrees,
		const int	bgColor )

Definition at line 1857 of file gd_interpolation.c.

gdImageRotateBilinear()

gdImagePtr gdImageRotateBilinear	(	gdImagePtr	src,
		const float	degrees,
		const int	bgColor )

Definition at line 1742 of file gd_interpolation.c.

gdImageRotateGeneric()

gdImagePtr gdImageRotateGeneric	(	gdImagePtr	src,
		const float	degrees,
		const int	bgColor )

Definition at line 1688 of file gd_interpolation.c.

gdImageRotateInterpolated()

gdImagePtr gdImageRotateInterpolated	(	const gdImagePtr	src,
		const float	angle,
		int	bgcolor )

Definition at line 2123 of file gd_interpolation.c.

gdImageRotateNearestNeighbour()

gdImagePtr gdImageRotateNearestNeighbour	(	gdImagePtr	src,
		const float	degrees,
		const int	bgColor )

Definition at line 1631 of file gd_interpolation.c.

gdImageScale()

gdImagePtr gdImageScale	(	const gdImagePtr	src,
		const unsigned int	new_width,
		const unsigned int	new_height )

Definition at line 1577 of file gd_interpolation.c.

gdImageScaleBicubicFixed()

gdImagePtr gdImageScaleBicubicFixed	(	gdImagePtr	src,
		const unsigned int	width,
		const unsigned int	height )

Definition at line 1352 of file gd_interpolation.c.

gdImageScaleBilinear()

gdImagePtr gdImageScaleBilinear	(	gdImagePtr	im,
		const unsigned int	new_width,
		const unsigned int	new_height )

Definition at line 1343 of file gd_interpolation.c.

gdImageScaleNearestNeighbour()

gdImagePtr gdImageScaleNearestNeighbour	(	gdImagePtr	im,
		const unsigned int	width,
		const unsigned int	height )

Definition at line 1097 of file gd_interpolation.c.

gdImageScaleTwoPass()

gdImagePtr gdImageScaleTwoPass	(	const gdImagePtr	src,
		const unsigned int	src_width,
		const unsigned int	src_height,
		const unsigned int	new_width,
		const unsigned int	new_height )

Definition at line 1048 of file gd_interpolation.c.

gdImageSetInterpolationMethod()

int gdImageSetInterpolationMethod	(	gdImagePtr	im,
		gdInterpolationMethod	id )

Definition at line 2466 of file gd_interpolation.c.

gdTransformAffineBoundingBox()

int gdTransformAffineBoundingBox	(	gdRectPtr	src,
		const double	affine[6],
		gdRectPtr	bbox )

Function: gdTransformAffineBoundingBox Returns the bounding box of an affine transformation applied to a rectangular area <gdRect>

Parameters: src - Rectangular source area for the affine transformation affine - the affine transformation bbox - the resulting bounding box

Returns: GD_TRUE if the affine is rectilinear or GD_FALSE

Definition at line 2426 of file gd_interpolation.c.

gdTransformAffineCopy()

int gdTransformAffineCopy	(	gdImagePtr	dst,
		int	dst_x,
		int	dst_y,
		const gdImagePtr	src,
		gdRectPtr	src_region,
		const double	affine[6] )

Function: gdTransformAffineCopy Applies an affine transformation to a region and copy the result in a destination to the given position.

Parameters: dst - Image to draw the transformed image src - Source image dstX - X position in the destination image dstY - Y position in the destination image src_area - Rectangular region to rotate in the src image

Returns: GD_TRUE on success or GD_FALSE on failure

Definition at line 2301 of file gd_interpolation.c.

gdTransformAffineGetImage()

int gdTransformAffineGetImage	(	gdImagePtr *	dst,
		const gdImagePtr	src,
		gdRectPtr	src_area,
		const double	affine[6] )

Function: gdTransformAffineGetImage Applies an affine transformation to a region and return an image containing the complete transformation.

Parameters: dst - Pointer to a gdImagePtr to store the created image, NULL when the creation or the transformation failed src - Source image src_area - rectangle defining the source region to transform dstY - Y position in the destination image affine - The desired affine transformation

Returns: GD_TRUE if the affine is rectilinear or GD_FALSE

Definition at line 2235 of file gd_interpolation.c.

getPixelInterpolated()

int getPixelInterpolated	(	gdImagePtr	im,
		const double	x,
		const double	y,
		const int	bgColor )

Function: getPixelInterpolated Returns the interpolated color value using the default interpolation method. The returned color is always in the ARGB format (truecolor).

Parameters: im - Image to set the default interpolation method y - X value of the ideal position y - Y value of the ideal position method - Interpolation method <gdInterpolationMethod>

Returns: GD_TRUE if the affine is rectilinear or GD_FALSE

See also: <gdSetInterpolationMethod>

Definition at line 739 of file gd_interpolation.c.