Package me.lemire.integercompression

Class S16

java.lang.Object

me.lemire.integercompression.S16

public final class S16
extends Object

Version of Simple16 for NewPFD and OptPFD.

Adapted by D. Lemire from the Apache Lucene project.

Constructor Summary

Constructors

Constructor	Description
S16()

Method Summary

Modifier and Type	Method	Description
static int	compress(int[] in, int currentPos, int inlength, int[] out, int tmpoutpos)	Compress an integer array using Simple16
static final int	compressblock(int[] out, int outOffset, int[] in, int inOffset, int n)	Compress an integer array using Simple16
static final int	decompressblock(int[] out, int outOffset, int[] in, int inOffset, int n)	Decompress an integer array using Simple16
static int	estimatecompress(int[] in, int currentPos, int inlength)	Estimate size of the compressed output.
static void	uncompress(int[] in, int tmpinpos, int inlength, int[] out, int currentPos, int outlength)	Uncompressed data from an input array into an output array

Methods inherited from class java.lang.Object

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

Constructor Details

S16

public S16()

Method Details

compress

public static int compress(int[] in,
 int currentPos,
 int inlength,
 int[] out,
 int tmpoutpos)

Compress an integer array using Simple16

Parameters:

in - array to compress

currentPos - where to start reading

inlength - how many integers to read

out - output array

tmpoutpos - location in the output array

Returns:

the number of 32-bit words written (in compressed form)

estimatecompress

public static int estimatecompress(int[] in,
 int currentPos,
 int inlength)

Estimate size of the compressed output.

Parameters:

in - array to compress

currentPos - where to start reading

inlength - how many integers to read

Returns:

estimated size of the output (in 32-bit integers)

compressblock

public static final int compressblock(int[] out,
 int outOffset,
 int[] in,
 int inOffset,
 int n)

Compress an integer array using Simple16

Parameters:

out - the compressed output

outOffset - the offset of the output in the number of integers

in - the integer input array

inOffset - the offset of the input in the number of integers

n - the number of elements to be compressed

Returns:

the size of the outputs in 32-bit integers

decompressblock

public static final int decompressblock(int[] out,
 int outOffset,
 int[] in,
 int inOffset,
 int n)

Decompress an integer array using Simple16

Parameters:

out - the decompressed output

outOffset - the offset of the output in the number of integers

in - the compressed input array

inOffset - the offset of the input in the number of integers

n - the number of elements to be compressed

Returns:

the number of processed integers

uncompress

public static void uncompress(int[] in,
 int tmpinpos,
 int inlength,
 int[] out,
 int currentPos,
 int outlength)

Uncompressed data from an input array into an output array

Parameters:

in - input array (in compressed form)

tmpinpos - starting location in the compressed input array

inlength - how much data we wish the read (in 32-bit words)

out - output array (in decompressed form)

currentPos - current position in the output array

outlength - available data in the output array