Package eu.europa.esig.dss.pdf.visible

Class ImageUtils

java.lang.Object

eu.europa.esig.dss.pdf.visible.ImageUtils

public class ImageUtils
extends Object

Static utilities that helps in creating ImageAndResolution

Author:

pakeyser

Field Summary

Fields

Modifier and Type	Field	Description
static int	DEFAULT_FIRST_PAGE	Defines a number of a first page in a document

Method Summary

Modifier and Type	Method	Description
static int	drawSubtractionImage(BufferedImage img1, BufferedImage img2, BufferedImage outImg)	Draws the subtraction image and returns different pixels amount
static AnnotationBox	getImageBoundaryBox(SignatureImageParameters imageParameters)	Returns image boundary box.
static int	getImageType(BufferedImage image)
static float	getScaleFactor(int zoom)	Returns a coefficient applying to a signature field width/height calculation
static boolean	imageDimensionsEqual(BufferedImage img1, BufferedImage img2)	Checks if the dimensions of the provided images is equal
static boolean	imagesEqual(BufferedImage img1, BufferedImage img2)	Checks if the two given images are equal
static boolean	isTransparent(BufferedImage bufferedImage)
static BufferedImage	read(InputStream is)	Reads image from InputStream.
static ImageAndResolution	readDisplayMetadata(DSSDocument image)	Reads image's metadata
static BufferedImage	rotate(BufferedImage image, double angle)
static ImageAndResolution	secureReadMetadata(SignatureImageParameters imageParameters)	Reads image's metadata in a secure way.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

DEFAULT_FIRST_PAGE

public static final int DEFAULT_FIRST_PAGE

Defines a number of a first page in a document

See Also:

Constant Field Values

Method Details

secureReadMetadata

public static ImageAndResolution secureReadMetadata(SignatureImageParameters imageParameters)
                                             throws IOException

Reads image's metadata in a secure way. If metadata is not accessible from image, returns values from imageParameters

Parameters:

imageParameters - SignatureImageParameters

Returns:

ImageAndResolution metadata

Throws:

IOException - in case of image reading error

readDisplayMetadata

public static ImageAndResolution readDisplayMetadata(DSSDocument image)
                                              throws IOException

Reads image's metadata

Parameters:

image - DSSDocument image to read metadata from

Returns:

ImageAndResolution metadata

Throws:

IOException - in case of image reading error

getImageBoundaryBox

public static AnnotationBox getImageBoundaryBox(SignatureImageParameters imageParameters)

Returns image boundary box. Tries to retrieve explicitly set values in the parameters, in other case reads dimensions from the provided image

Parameters:

imageParameters - SignatureImageParameters

Returns:

AnnotationBox

getScaleFactor

public static float getScaleFactor(int zoom)

Returns a coefficient applying to a signature field width/height calculation

Parameters:

zoom - - zoom value to compute scale factor from

Returns:

float scale factor

read

public static BufferedImage read(InputStream is)
                          throws IOException

Reads image from InputStream. Detects and converts CMYK images to RGB if needed

Parameters:

is - InputStream to read the image from

Returns:

BufferedImage

Throws:

IOException - - in case of InputStream reading error

rotate

public static BufferedImage rotate(BufferedImage image,
double angle)

isTransparent

public static boolean isTransparent(BufferedImage bufferedImage)

getImageType

public static int getImageType(BufferedImage image)

imagesEqual

public static boolean imagesEqual(BufferedImage img1,
BufferedImage img2)

Checks if the two given images are equal

Parameters:

img1 - BufferedImage

img2 - BufferedImage

Returns:

TRUE if the two images are equal, FALSE otherwise

imageDimensionsEqual

public static boolean imageDimensionsEqual(BufferedImage img1,
BufferedImage img2)

Checks if the dimensions of the provided images is equal

Parameters:

img1 - BufferedImage

img2 - BufferedImage

Returns:

TRUE if the size dimensions of both images is equal, FALSE otherwise

drawSubtractionImage

public static int drawSubtractionImage(BufferedImage img1,
BufferedImage img2,
BufferedImage outImg)

Draws the subtraction image and returns different pixels amount

Parameters:

img1 - BufferedImage to compare

img2 - BufferedImage to compare

outImg - BufferedImage the output result (subtraction image)

Returns:

amount of different pixels between two images