loci.formats.codec
Class LZWCodec

java.lang.Object
  loci.formats.codec.BaseCodec
      loci.formats.codec.LZWCodec

All Implemented Interfaces:

Codec

public class LZWCodec
extends BaseCodec
implements Codec

Implements basic LZW compression and decompression, as outlined in the TIFF 6.0 Specification at http://partners.adobe.com/asn/developer/pdfs/tn/TIFF6.pdf (page 61).

Source code:

Trac, SVN

Author:

Eric Kjellman egkjellman at wisc.edu, Curtis Rueden ctrueden at wisc.edu, Wayne Rasband wsr at nih.gov

Field Summary

protected static int	CLEAR_CODE
protected static int	EOI_CODE

Constructor Summary

LZWCodec()

Method Summary

byte[]	compress(byte[] input, int x, int y, int[] dims, Object options) Compresses a block of data using LZW compression.
byte[]	decompress(byte[] input, Object options) Decodes an LZW-compressed data block.
static void	main(String[] args) Main testing method.

Methods inherited from class loci.formats.codec.BaseCodec

compress, decompress, decompress, decompress, test

Methods inherited from class java.lang.Object

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

Methods inherited from interface loci.formats.codec.Codec

compress, decompress, decompress, decompress

Field Detail

CLEAR_CODE

protected static final int CLEAR_CODE

See Also:

Constant Field Values

EOI_CODE

protected static final int EOI_CODE

See Also:

Constant Field Values

Constructor Detail

LZWCodec

public LZWCodec()

Method Detail

compress

public byte[] compress(byte[] input,
                       int x,
                       int y,
                       int[] dims,
                       Object options)
                throws loci.formats.FormatException

Compresses a block of data using LZW compression. If input is null or of 0 length, simply returns input.

Specified by:

compress in interface Codec

Parameters:

input - the data to be compressed

x - ignored for LZW.

y - ignored for LZW.

dims - ignored for LZW.

options - ignored for LZW.

Returns:

The compressed data

Throws:

loci.formats.FormatException - If input is not a compressed data block of the appropriate type.

decompress

public byte[] decompress(byte[] input,
                         Object options)
                  throws loci.formats.FormatException

Decodes an LZW-compressed data block.

Specified by:

decompress in interface Codec

Parameters:

input - the data to be decompressed

options - Options to be used during decompression.

Returns:

The decompressed data

Throws:

loci.formats.FormatException - If input is not an LZW-compressed data block.

main

public static void main(String[] args)
                 throws loci.formats.FormatException

Main testing method.

Parameters:

args - ignored

Throws:

loci.formats.FormatException - Can only occur if there is a bug in the compress method.