org.xiph.speex
Class Bits

java.lang.Object
  org.xiph.speex.Bits

public class Bits

extends java.lang.Object

Speex bit packing and unpacking class.

Version:

$Revision: 1.5 $

Author:

Jim Lawrence, helloNetwork.com, Marc Gimpel, Wimba S.A. (marc@wimba.com)

Field Summary

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
static int	DEFAULT_BUFFER_SIZE Default buffer size

Constructor Summary

Bits()

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.

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_BUFFER_SIZE

public static final int DEFAULT_BUFFER_SIZE

Default buffer size

See Also:

Constant Field Values

bytes

private byte[] bytes

"raw" data

bytePtr

private int bytePtr

Position of the byte "cursor"

bitPtr

private int bitPtr

Position of the bit "cursor" within the current byte

Constructor Detail

Bits

public Bits()

Method Detail

init

public void init()

Initialise the bit packing variables.

advance

public void advance(int n)

Advance n bits.

Parameters:

n - - the number of bits to advance.

setBuffer

protected void setBuffer(byte[] newBuffer)

Sets the buffer to the given value.

Parameters:

newBuffer -

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 -

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.

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.

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.