ImageIO : Java Glossary

javax.imageio.ImageIO lets you save and restore Images to disk in a platform independent format. It works using plug-in modules that handle various formats including gif, png and jpeg (all lower case, or all upper case, but not mixed). jpeg or jpg is acceptable. Use ImageIO. getWriterFormatNames() to find out which types are supported on your platform:

Early versions of JAI (Java Advanced Imaging) did not support writing gif images because at the time the format was proprietary. Now the patent has expired.

With ImageIO, instead of Image you use BufferedImage which is a subclass of Image and can thus be used in any of the familiar tools that work with Images. Introduced with Java 1.4.

Loading an Image from raw bytes

Here raw bytes represent the image of a *.gif, *.png or

Saving an Image to raw bytes

Loading a BufferedImage from a file

// file to BufferedImage
import java.awt.image. BufferedImage;
import java.io.File;
import javax.imageio.ImageIO;
...
BufferedImage image = ImageIO.read( new File( "rabbit.jpg" ) );

Saving a BufferedImage to a file

// BufferedImage to File
import javax.imageio.ImageIO;
import java.awt.image.BufferedImage;
import java.io.File;
...
ImageIO.write( aBufferedImage, "jpeg" /* "png" "jpeg" ... format desired */,
               new File ( "snap.jpg" ) /* target */ );

ImageWriteParam is a way of controlling exactly how the image in encoded. There is currently no PNG (Portable Network Graphics) support for it. This is not for injecting meta info.

Loading a BufferedImage from a Resource

Loading a BufferedImage from an URL (Uniform Resource Locator)

Converting Image to BufferedImage

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