org.xiph.speex

Class Bits


public class Bits
extends java.lang.Object

Speex bit packing and unpacking class.
Version:
$Revision: 1.2 $
Authors:
Jim Lawrence, helloNetwork.com
Marc Gimpel, Wimba S.A. (mgimpel@horizonwimba.com)

Field Summary

static int
DEFAULT_BUFFER_SIZE
Default buffer size
private int
bitPtr
Position of the bit "cursor" within the current byte
private int
bytePtr
Position of the byte "cursor"
private byte[]
bytes
"raw" data

Method Summary

void
advance(int n)
Advance n bits.
byte[]
getBuffer()
Returns the current buffer array.
int
getBufferSize()
Returns the number of bytes used in the current buffer.
void
init()
Initialise the bit packing variables.
void
pack(int data, int nbBits)
Write N bits of the given data to the buffer.
int
peek()
Take a peek at the next bit.
void
read_from(byte[] newbytes, int offset, int len)
Read the given array into the buffer.
protected void
setBuffer(byte[] newBuffer)
Sets the buffer to the given value.
int
unpack(int nbBits)
Read the next N bits from the buffer.

Field Details

DEFAULT_BUFFER_SIZE

public static final int DEFAULT_BUFFER_SIZE
Default buffer size
Field Value:
1024

bitPtr

private int bitPtr
Position of the bit "cursor" within the current byte

bytePtr

private int bytePtr
Position of the byte "cursor"

bytes

private byte[] bytes
"raw" data

Method Details

advance

public void advance(int n)
Advance n bits.
Parameters:
n - - the number of bits to advance.

getBuffer

public byte[] getBuffer()
Returns the current buffer array.
Returns:
the current buffer array.

getBufferSize

public int getBufferSize()
Returns the number of bytes used in the current buffer.
Returns:
the number of bytes used in the current buffer.

init

public void init()
Initialise the bit packing variables.

pack

public void pack(int data,
                 int nbBits)
Write N bits of the given data to the buffer.
Parameters:
data - - the data to write.
nbBits - - the number of bits of the data to write.

peek

public int peek()
Take a peek at the next bit.
Returns:
the next bit.

read_from

public void read_from(byte[] newbytes,
                      int offset,
                      int len)
Read the given array into the buffer.
Parameters:
newbytes -
offset -
len -

setBuffer

protected void setBuffer(byte[] newBuffer)
Sets the buffer to the given value.
Parameters:
newBuffer -

unpack

public int unpack(int nbBits)
Read the next N bits from the buffer.
Parameters:
nbBits - - the number of bits to read.
Returns:
the next N bits from the buffer.

Copyright © 1999-2004 Wimba S.A. All Rights Reserved.