echopoint.image
Class PngEncoder

java.lang.Object
  echopoint.image.PngEncoder

All Implemented Interfaces:

ImageEncoder, java.io.Serializable

public class PngEncoder

extends java.lang.Object

implements ImageEncoder, java.io.Serializable

PngEncoder implements the ImageEncoder interface and hence can take a java.awt.Image object and encode it as a PNG output stream.

The Image can have a DirectColorModel or an IndexColorModel.

NOTE : While the Echo framework has a PNG encoder built in to it, it currently does not handle transparency correctly. Therefore this encoder has been provided.

See Also:

Serialized Form

Constructor Summary

PngEncoder()
Constructs a PngEncoder ready to start encoding, with the Alpha channel being encoded.

Method Summary

void	encode(java.awt.Image image, java.io.OutputStream out)
java.lang.String	getContentType()
boolean	isEncodeAlpha() This returns true if the Alpha channel of the image will be encoded
void	setEncodeAlpha(boolean b) If this is set to true then the Alpha channel of the image will be encoded.

Methods inherited from class java.lang.Object

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

Constructor Detail

PngEncoder

public PngEncoder()

Constructs a PngEncoder ready to start encoding, with the Alpha channel being encoded.

Method Detail

encode

public void encode(java.awt.Image image,
                   java.io.OutputStream out)
            throws java.io.IOException

Specified by:

encode in interface ImageEncoder

Throws:

java.io.IOException

See Also:

ImageEncoder.encode(java.awt.Image, java.io.OutputStream)

getContentType

public java.lang.String getContentType()

Specified by:

getContentType in interface ImageEncoder

See Also:

ImageEncoder.getContentType()

isEncodeAlpha

public boolean isEncodeAlpha()

This returns true if the Alpha channel of the image will be encoded

Returns:

- true if the Alpha channel of the image will be encoded

setEncodeAlpha

public void setEncodeAlpha(boolean b)

If this is set to true then the Alpha channel of the image will be encoded. By this value is true by default.

Parameters:

b - - true if the Alpha channel of the image is to be encoded