gifAnimation

Class GifEncoder

java.lang.Object

gifAnimation.GifEncoder

public class GifEncoder
extends Object

Class AnimatedGifEncoder - Encodes a GIF file consisting of one or more frames.

  Example:
     AnimatedGifEncoder e = new AnimatedGifEncoder();
     e.start(outputFileName);
     e.setDelay(1000);   // 1 frame per sec
     e.addFrame(image1);
     e.addFrame(image2);
     e.finish();
 

No copyright asserted on the source code of this class. May be used for any purpose, however, refer to the Unisys LZW patent for restrictions on use of the associated LZWEncoder class. Please forward any corrections to kweiner@fmsware.com.

Author:

Kevin Weiner, FM Software

Constructor Summary

Constructors

Constructor and Description
GifEncoder()

Method Summary

Modifier and Type	Method and Description
boolean	addFrame(BufferedImage im) Adds next GIF frame.
boolean	finish() Flushes any pending data and closes output file.
void	setDelay(int ms) Sets the delay time between each frame, or changes it for subsequent frames (applies to last frame added).
void	setDispose(int code) Sets the GIF frame disposal code for the last added frame and any subsequent frames.
void	setFrameRate(float fps) Sets frame rate in frames per second.
void	setQuality(int quality) Sets quality of color quantization (conversion of images to the maximum 256 colors allowed by the GIF specification).
void	setRepeat(int iter) Sets the number of times the set of GIF frames should be played.
void	setSize(int w, int h) Sets the GIF frame size.
void	setTransparent(Color c) Sets the transparent color for the last added frame and any subsequent frames.
boolean	start(OutputStream os) Initiates GIF file creation on the given stream.
boolean	start(String file) Initiates writing of a GIF file with the specified name.

Methods inherited from class java.lang.Object

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

Constructor Detail

GifEncoder

public GifEncoder()

Method Detail

setDelay

public void setDelay(int ms)

Sets the delay time between each frame, or changes it for subsequent frames (applies to last frame added).

Parameters:

ms - int delay time in milliseconds

setDispose

public void setDispose(int code)

Sets the GIF frame disposal code for the last added frame and any subsequent frames. Default is 0 if no transparent color has been set, otherwise 2.

Parameters:

code - int disposal code.

setRepeat

public void setRepeat(int iter)

Sets the number of times the set of GIF frames should be played. Default is 1; 0 means play indefinitely. Must be invoked before the first image is added.

Parameters:

iter - int number of iterations.

setTransparent

public void setTransparent(Color c)

Sets the transparent color for the last added frame and any subsequent frames. Since all colors are subject to modification in the quantization process, the color in the final palette for each frame closest to the given color becomes the transparent color for that frame. May be set to null to indicate no transparent color.

Parameters:

c - Color to be treated as transparent on display.

addFrame

public boolean addFrame(BufferedImage im)

Adds next GIF frame. The frame is not written immediately, but is actually deferred until the next frame is received so that timing data can be inserted. Invoking finish() flushes all frames. If setSize was not invoked, the size of the first image is used for all subsequent frames.

Parameters:

im - BufferedImage containing frame to write.

Returns:

true if successful.

finish

public boolean finish()

Flushes any pending data and closes output file. If writing to an OutputStream, the stream is not closed.

Returns:

true if data output closed

setFrameRate

public void setFrameRate(float fps)

Sets frame rate in frames per second. Equivalent to setDelay(1000/fps).

Parameters:

fps - float frame rate (frames per second)

setQuality

public void setQuality(int quality)

Sets quality of color quantization (conversion of images to the maximum 256 colors allowed by the GIF specification). Lower values (minimum = 1) produce better colors, but slow processing significantly. 10 is the default, and produces good color mapping at reasonable speeds. Values greater than 20 do not yield significant improvements in speed.

Parameters:

quality - int greater than 0.

setSize

public void setSize(int w,
                    int h)

Sets the GIF frame size. The default size is the size of the first frame added if this method is not invoked.

Parameters:

w - int frame width.

h - int frame width.

start

public boolean start(OutputStream os)

Initiates GIF file creation on the given stream. The stream is not closed automatically.

Parameters:

os - OutputStream on which GIF images are written.

Returns:

false if initial write failed.

start

public boolean start(String file)

Initiates writing of a GIF file with the specified name.

Parameters:

file - String containing output file name.

Returns:

false if open or initial write failed.