sim.util.media
Class PNGEncoder

java.lang.Object
  sim.util.media.PNGEncoder

public class PNGEncoder
extends java.lang.Object

PNGEncoder takes a Java Image object and creates a byte string which can be saved as a PNG file. The Image is presumed to use the DirectColorModel.

This code is taken, with permission, from J. David Eisenberg (david@catcode.com), and is distributed under the Artistic License.

Field Summary

static int	FILTER_NONE Constants for filters
static int	FILTER_SUB
static int	FILTER_UP

Constructor Summary

PNGEncoder()
Class constructor

PNGEncoder(java.awt.Image image)
Class constructor specifying Image to encode, with no alpha channel encoding.

PNGEncoder(java.awt.Image image, boolean encodeAlpha)
Class constructor specifying Image to encode, and whether to encode alpha.

PNGEncoder(java.awt.Image image, boolean encodeAlpha, int whichFilter)
Class constructor specifying Image to encode, whether to encode alpha, and filter to use.

PNGEncoder(java.awt.Image image, boolean encodeAlpha, int whichFilter, int compLevel)
Class constructor specifying Image source to encode, whether to encode alpha, filter to use, and compression level.

Method Summary

int	getCompressionLevel() Retrieve compression level
boolean	getEncodeAlpha() Retrieve alpha encoding status.
int	getFilter() Retrieve filtering scheme
byte[]	pngEncode() Creates an array of bytes that is the PNG equivalent of the current image, specifying whether to encode alpha or not.
void	setCompressionLevel(int level) Set the compression level to use
void	setEncodeAlpha(boolean encodeAlpha) Set the alpha encoding on or off.
void	setFilter(int whichFilter) Set the filter to use
void	setImage(java.awt.Image image) Set the image to be encoded

Methods inherited from class java.lang.Object

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

Field Detail

FILTER_NONE

public static final int FILTER_NONE

Constants for filters

See Also:

Constant Field Values

FILTER_SUB

public static final int FILTER_SUB

See Also:

Constant Field Values

FILTER_UP

public static final int FILTER_UP

See Also:

Constant Field Values

Constructor Detail

PNGEncoder

public PNGEncoder()

Class constructor

PNGEncoder

public PNGEncoder(java.awt.Image image)

Class constructor specifying Image to encode, with no alpha channel encoding.

Parameters:

image - A Java Image object which uses the DirectColorModel

See Also:

Image

PNGEncoder

public PNGEncoder(java.awt.Image image,
                  boolean encodeAlpha)

Class constructor specifying Image to encode, and whether to encode alpha.

Parameters:

image - A Java Image object which uses the DirectColorModel

encodeAlpha - Encode the alpha channel? false=no; true=yes

See Also:

Image

PNGEncoder

public PNGEncoder(java.awt.Image image,
                  boolean encodeAlpha,
                  int whichFilter)

Class constructor specifying Image to encode, whether to encode alpha, and filter to use.

Parameters:

image - A Java Image object which uses the DirectColorModel

encodeAlpha - Encode the alpha channel? false=no; true=yes

whichFilter - 0=none, 1=sub, 2=up

See Also:

Image

PNGEncoder

public PNGEncoder(java.awt.Image image,
                  boolean encodeAlpha,
                  int whichFilter,
                  int compLevel)

Class constructor specifying Image source to encode, whether to encode alpha, filter to use, and compression level.

Parameters:

image - A Java Image object

encodeAlpha - Encode the alpha channel? false=no; true=yes

whichFilter - 0=none, 1=sub, 2=up

compLevel - 0..9

See Also:

Image

Method Detail

setImage

public void setImage(java.awt.Image image)

Set the image to be encoded

Parameters:

image - A Java Image object which uses the DirectColorModel

See Also:

Image, DirectColorModel

pngEncode

public byte[] pngEncode()

Creates an array of bytes that is the PNG equivalent of the current image, specifying whether to encode alpha or not.

Parameters:

encodeAlpha - boolean false=no alpha, true=encode alpha

Returns:

an array of bytes, or null if there was a problem

setEncodeAlpha

public void setEncodeAlpha(boolean encodeAlpha)

Set the alpha encoding on or off.

Parameters:

encodeAlpha - false=no, true=yes

getEncodeAlpha

public boolean getEncodeAlpha()

Retrieve alpha encoding status.

Returns:

boolean false=no, true=yes

setFilter

public void setFilter(int whichFilter)

Set the filter to use

Parameters:

whichFilter - from constant list

getFilter

public int getFilter()

Retrieve filtering scheme

Returns:

int (see constant list)

setCompressionLevel

public void setCompressionLevel(int level)

Set the compression level to use

Parameters:

level - 0 through 9

getCompressionLevel

public int getCompressionLevel()

Retrieve compression level

Returns:

int in range 0-9