Image Comparison

Data Structures
struct	gdImagePerceptualDiffOptions
	Options for perceptual image comparison. More...
struct	gdImagePerceptualDiffResult
	Result of perceptual image comparison. More...

Macros
#define	GD_CMP_IMAGE   1
#define	GD_CMP_NUM_COLORS   2
#define	GD_CMP_COLOR   4
#define	GD_CMP_SIZE_X   8
#define	GD_CMP_SIZE_Y   16
#define	GD_CMP_TRANSPARENT   32
#define	GD_CMP_BACKGROUND   64
#define	GD_CMP_INTERLACE   128
#define	GD_CMP_TRUECOLOR   256

Enumerations
enum	gdImageDiffMode { GD_IMAGE_DIFF_NONE , GD_IMAGE_DIFF_OVERLAY , GD_IMAGE_DIFF_MASK }
	Options for perceptual image comparison mode. More...

Functions
int	gdImageCompare (gdImagePtr im1, gdImagePtr im2)
	Compare two images.

Detailed Description

Macro Definition Documentation

GD_CMP_BACKGROUND

#define GD_CMP_BACKGROUND   64

Background color differs

GD_CMP_COLOR

#define GD_CMP_COLOR   4

Image colors differ

GD_CMP_IMAGE

#define GD_CMP_IMAGE   1

Actual image IS different

GD_CMP_INTERLACE

#define GD_CMP_INTERLACE   128

Interlaced setting differs

GD_CMP_NUM_COLORS

#define GD_CMP_NUM_COLORS   2

Number of colors in pallette differ

GD_CMP_SIZE_X

#define GD_CMP_SIZE_X   8

Image width differs

GD_CMP_SIZE_Y

#define GD_CMP_SIZE_Y   16

Image heights differ

GD_CMP_TRANSPARENT

#define GD_CMP_TRANSPARENT   32

Transparent color differs

GD_CMP_TRUECOLOR

#define GD_CMP_TRUECOLOR   256

Truecolor vs palette differs

Enumeration Type Documentation

gdImageDiffMode

enum gdImageDiffMode

Options for perceptual image comparison mode.

Enumerator
GD_IMAGE_DIFF_NONE	No difference
GD_IMAGE_DIFF_OVERLAY	Overlay difference
GD_IMAGE_DIFF_MASK	Mask difference

Function Documentation

gdImageCompare()

int gdImageCompare	(	gdImagePtr	im1,
		gdImagePtr	im2
	)

Compare two images.

compare two images and some of its attributes. The images must be of the same size, otherwise the function will return -1. For accurate image content comparison, use gdImagePerceptualDiff instead.

Parameters

im1	An image.
im2	Another image.

Returns

A bitmask of <Image Comparison> flags where each set flag signals which attributes of the images are different.

< Interlaced setting differs

< Transparent color differs

< Truecolor vs palette differs

< Image width differs

< Actual image IS different

< Image heights differ

< Actual image IS different

< Number of colors in pallette differ

< Image colors differ

< Actual image IS different

< Image colors differ

< Actual image IS different

< Image colors differ

< Actual image IS different

< Image colors differ