org.itadaki.bzip2

Class BZip2MTFAndRLE2StageEncoder

java.lang.Object

org.itadaki.bzip2.BZip2MTFAndRLE2StageEncoder

public class BZip2MTFAndRLE2StageEncoder
extends Object

An encoder for the BZip2 Move To Front Transform and Run-Length Encoding[2] stages
Although conceptually these two stages are separate, it is computationally efficient to perform them in one pass.

Constructor Summary

Constructors

Constructor and Description
BZip2MTFAndRLE2StageEncoder(int[] bwtBlock, int bwtLength, boolean[] bwtValuesPresent)

Method Summary

Methods

Modifier and Type	Method and Description
void	encode() Performs the Move To Front transform and Run Length Encoding[1] stages
int	getMtfAlphabetSize()
char[]	getMtfBlock()
int	getMtfLength()
int[]	getMtfSymbolFrequencies()

Methods inherited from class java.lang.Object

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

Constructor Detail

BZip2MTFAndRLE2StageEncoder

public BZip2MTFAndRLE2StageEncoder(int[] bwtBlock,
                           int bwtLength,
                           boolean[] bwtValuesPresent)

Parameters:

bwtBlock - The Burrows Wheeler Transformed block data

bwtLength - The actual length of the BWT data

bwtValuesPresent - The values that are present within the BWT data. For each index, true if that value is present within the data, otherwise false

Method Detail

encode

public void encode()

Performs the Move To Front transform and Run Length Encoding[1] stages

getMtfBlock

public char[] getMtfBlock()

Returns:

The encoded MTF block

getMtfLength

public int getMtfLength()

Returns:

The actual length of the MTF block

getMtfAlphabetSize

public int getMtfAlphabetSize()

Returns:

The size of the MTF block's alphabet

getMtfSymbolFrequencies

public int[] getMtfSymbolFrequencies()

Returns:

The frequencies of the MTF block's symbols