Package org.xwiki.rendering.wikimodel.images

Class ImageUtil

java.lang.Object

org.xwiki.rendering.wikimodel.images.ImageUtil

public class ImageUtil
extends Object

Contains utility methods dealing with images like image size definition or creation of thumbnails (reduced copies of images).

Since:

4.0M1

Version:

$Id: 2b0c0e29d583c58caa42a22a0353693cbb8f7e3f $

Constructor Summary

Constructors

Constructor	Description
ImageUtil()

Method Summary

Modifier and Type	Method	Description
static void	createThumb(InputStream input, OutputStream output, int thumbWidth, int thumbHeight, String format)	Create a reduced image (thumb) of an image from the given input stream.
static int[]	getImageSize(InputStream input)	Returns the size (width and height) of an image from the given input stream.
static int[]	getImageSize(InputStream input, int maxWidth, int maxHeight)	Returns the possible size of an image from the given input stream; the returned size does not overcome the specified maximal borders but keeps the ratio of the image.
static int[]	getNewSize(int width, int height, int maxWidth, int maxHeight)	Calculates new size of an image with the specified max borders keeping the ratio between height and width of the image.

Methods inherited from class java.lang.Object

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

Constructor Detail

ImageUtil

public ImageUtil()

Method Detail

createThumb

public static void createThumb(InputStream input,
                               OutputStream output,
                               int thumbWidth,
                               int thumbHeight,
                               String format)
                        throws IOException

Create a reduced image (thumb) of an image from the given input stream. Possible output formats are "jpg" or "png" (no "gif"; it is possible to read "gif" files, but not to write). The resulting thumb is written to the output stream. The both streams will be explicitly closed by this method. This method keeps the ratio width/height of the initial image. If both dimensions of the initial image is less than the specified boundaries it is not re-scaled; it is written to the output stream as is.

Parameters:

input - the input stream containing the image to reduce

output - the output stream where the resulting reduced image is written

thumbWidth - the maximal width of the reduced image

thumbHeight - the maximal height of the reduced image

format - the output format of the reduced image; it can be "jpg", "png", ...

Throws:

IOException

getImageSize

public static int[] getImageSize(InputStream input)
                          throws IOException

Returns the size (width and height) of an image from the given input stream. This method closes the given stream.

Parameters:

input - the input stream with an image

Returns:

the size (width and height) of an image from the given input stream

Throws:

IOException

getImageSize

public static int[] getImageSize(InputStream input,
                                 int maxWidth,
                                 int maxHeight)
                          throws IOException

Returns the possible size of an image from the given input stream; the returned size does not overcome the specified maximal borders but keeps the ratio of the image. This method closes the given stream.

Parameters:

input - the input stream with an image

maxWidth - the maximal width

maxHeight - the maximal height

Returns:

the possible size of an image from the given input stream; the returned size does not overcome the specified maximal borders but keeps the ratio of the image

Throws:

IOException

getNewSize

public static int[] getNewSize(int width,
                               int height,
                               int maxWidth,
                               int maxHeight)

Calculates new size of an image with the specified max borders keeping the ratio between height and width of the image.

Parameters:

width - the initial width of an image

height - the initial height of an image

maxWidth - the maximal width of an image

maxHeight - the maximal height of an image

Returns:

a new size of an image where the height and width don't overcome the specified borders; the size keeps the initial image ratio between width and height