com.lowagie.text.pdf.codec

Class GifImage

public class GifImage extends Object

Reads gif images of all types. All the images in a gif are read in the constructors and can be retrieved with other methods.

Author: Paulo Soares (psoares@consiste.pt)

Nested Class Summary
static class	GifImage.GifFrame

Field Summary
protected int	bgColor
protected int	bgIndex
protected byte[]	block
protected int	blockSize
protected int	delay
protected int	dispose
protected ArrayList	frames
protected byte[]	fromData
protected URL	fromUrl
protected boolean	gctFlag
protected int	height
protected int	ih
protected DataInputStream	in
protected boolean	interlace
protected int	iw
protected int	ix
protected int	iy
protected boolean	lctFlag
protected int	lctSize
protected int	m_bpc
protected byte[]	m_curr_table
protected int	m_gbpc
protected byte[]	m_global_table
protected int	m_line_stride
protected byte[]	m_local_table
protected byte[]	m_out
protected static int	MaxStackSize
protected int	pixelAspect
protected byte[]	pixels
protected byte[]	pixelStack
protected short[]	prefix
protected byte[]	suffix
protected int	transIndex
protected boolean	transparency
protected int	width

Constructor Summary
	GifImage(URL url) Reads gif images from an URL.
	GifImage(String file) Reads gif images from a file.
	GifImage(byte[] data) Reads gif images from a byte array.
	GifImage(InputStream is) Reads gif images from a stream.

Method Summary
protected boolean	decodeImageData()
int	getFrameCount() Gets the number of frames the gif has.
int[]	getFramePosition(int frame) Gets the [x,y] position of the frame in reference to the logical screen.
Image	getImage(int frame) Gets the image from a frame.
int[]	getLogicalScreen() Gets the logical screen.
protected static int	newBpc(int bpc)
void	process(InputStream is)
protected int	readBlock() Reads next variable length block from input.
protected byte[]	readColorTable(int bpc)
protected void	readContents()
protected void	readGraphicControlExt() Reads Graphics Control Extension values
protected void	readHeader() Reads GIF file header information.
protected void	readImage() Reads next frame image
protected void	readLSD() Reads Logical Screen Descriptor
protected int	readShort() Reads next 16-bit value, LSB first
protected void	resetFrame() Resets frame state for reading next image.
protected void	setPixel(int x, int y, int v)
protected void	skip() Skips variable length blocks up to and including next zero length block.

Field Detail

bgColor

protected int bgColor

bgIndex

protected int bgIndex

block

protected byte[] block

blockSize

protected int blockSize

delay

protected int delay

dispose

protected int dispose

frames

protected ArrayList frames

fromData

protected byte[] fromData

fromUrl

protected URL fromUrl

gctFlag

protected boolean gctFlag

height

protected int height

ih

protected int ih

in

protected DataInputStream in

interlace

protected boolean interlace

iw

protected int iw

ix

protected int ix

iy

protected int iy

lctFlag

protected boolean lctFlag

lctSize

protected int lctSize

m_bpc

protected int m_bpc

m_curr_table

protected byte[] m_curr_table

m_gbpc

protected int m_gbpc

m_global_table

protected byte[] m_global_table

m_line_stride

protected int m_line_stride

m_local_table

protected byte[] m_local_table

m_out

protected byte[] m_out

MaxStackSize

protected static final int MaxStackSize

pixelAspect

protected int pixelAspect

pixels

protected byte[] pixels

pixelStack

protected byte[] pixelStack

prefix

protected short[] prefix

suffix

protected byte[] suffix

transIndex

protected int transIndex

transparency

protected boolean transparency

width

protected int width

Constructor Detail

GifImage

public GifImage(URL url)

Reads gif images from an URL.

Parameters: url the URL

Throws: IOException on error

GifImage

public GifImage(String file)

Reads gif images from a file.

Parameters: file the file

Throws: IOException on error

GifImage

public GifImage(byte[] data)

Reads gif images from a byte array.

Parameters: data the byte array

Throws: IOException on error

GifImage

public GifImage(InputStream is)

Reads gif images from a stream. The stream is not closed.

Parameters: is the stream

Throws: IOException on error

Method Detail

decodeImageData

protected boolean decodeImageData()

getFrameCount

public int getFrameCount()

Gets the number of frames the gif has.

Returns: the number of frames the gif has

getFramePosition

public int[] getFramePosition(int frame)

Gets the [x,y] position of the frame in reference to the logical screen.

Parameters: frame the frame

Returns: the [x,y] position of the frame

getImage

public Image getImage(int frame)

Gets the image from a frame. The first frame is 1.

Parameters: frame the frame to get the image from

Returns: the image

getLogicalScreen

public int[] getLogicalScreen()

Gets the logical screen. The images may be smaller and placed in some position in this screen to playback some animation. No image will be be bigger that this.

Returns: the logical screen dimensions as [x,y]