jj2000.j2k.entropy.decoder

Class EntropyDecoder

java.lang.Object

jj2000.j2k.wavelet.synthesis.MultiResImgDataAdapter

jj2000.j2k.entropy.decoder.EntropyDecoder

All Implemented Interfaces:

CBlkQuantDataSrcDec, InvWTData, MultiResImgData

Direct Known Subclasses:

StdEntropyDecoder

public abstract class EntropyDecoder
extends MultiResImgDataAdapter
implements CBlkQuantDataSrcDec

This is the abstract class from which all entropy decoders must inherit. This class implements the 'MultiResImgData', therefore it has the concept of a current tile and all operations are performed on the current tile.

Default implementations of the methods in 'MultiResImgData' are provided through the 'MultiResImgDataAdapter' abstract class.

Sign magnitude representation is used (instead of two's complement) for the output data. The most significant bit is used for the sign (0 if positive, 1 if negative). Then the magnitude of the quantized coefficient is stored in the next most significat bits. The most significant magnitude bit corresponds to the most significant bit-plane and so on.

See Also:

MultiResImgData, MultiResImgDataAdapter

Field Summary

Fields

Modifier and Type	Field and Description
static char	OPT_PREFIX The prefix for entropy decoder optiojns: 'C'
protected CodedCBlkDataSrcDec	src The bit stream transport from where to get the compressed data (the source)

Fields inherited from class jj2000.j2k.wavelet.synthesis.MultiResImgDataAdapter

mressrc, tIdx

Constructor Summary

Constructors

Constructor and Description
EntropyDecoder(CodedCBlkDataSrcDec src) Initializes the source of compressed data.

Method Summary

Methods

Modifier and Type	Method and Description
int	getCbULX() Returns the horizontal code-block partition origin.
int	getCbULY() Returns the vertical code-block partition origin.
static String[][]	getParameterInfo() Returns the parameters that are used in this class and implementing classes.
SubbandSyn	getSynSubbandTree(int t, int c) Returns the subband tree, for the specified tile-component.

Methods inherited from class jj2000.j2k.wavelet.synthesis.MultiResImgDataAdapter

getCompImgHeight, getCompImgWidth, getCompSubsX, getCompSubsY, getImgHeight, getImgULX, getImgULY, getImgWidth, getNomTileHeight, getNomTileWidth, getNumComps, getNumTiles, getNumTiles, getResULX, getResULY, getTile, getTileCompHeight, getTileCompWidth, getTileHeight, getTileIdx, getTilePartULX, getTilePartULY, getTileWidth, nextTile, setTile

Methods inherited from class java.lang.Object

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

Methods inherited from interface jj2000.j2k.quantization.dequantizer.CBlkQuantDataSrcDec

getCodeBlock, getInternCodeBlock

Methods inherited from interface jj2000.j2k.wavelet.synthesis.MultiResImgData

getCompImgHeight, getCompImgWidth, getCompSubsX, getCompSubsY, getImgHeight, getImgULX, getImgULY, getImgWidth, getNomTileHeight, getNomTileWidth, getNumComps, getNumTiles, getNumTiles, getResULX, getResULY, getTile, getTileCompHeight, getTileCompWidth, getTileHeight, getTileIdx, getTilePartULX, getTilePartULY, getTileWidth, nextTile, setTile

Field Detail

OPT_PREFIX

public static final char OPT_PREFIX

The prefix for entropy decoder optiojns: 'C'

See Also:

Constant Field Values

src

protected CodedCBlkDataSrcDec src

The bit stream transport from where to get the compressed data (the source)

Constructor Detail

EntropyDecoder

public EntropyDecoder(CodedCBlkDataSrcDec src)

Initializes the source of compressed data.

Parameters:

src - From where to obtain the compressed data.

Method Detail

getSynSubbandTree

public SubbandSyn getSynSubbandTree(int t,
                           int c)

Returns the subband tree, for the specified tile-component. This method returns the root element of the subband tree structure, see Subband and SubbandSyn. The tree comprises all the available resolution levels.

The number of magnitude bits ('magBits' member variable) for each subband is not initialized.

Specified by:

getSynSubbandTree in interface InvWTData

Specified by:

getSynSubbandTree in interface MultiResImgData

Parameters:

t - The index of the tile, from 0 to T-1.

c - The index of the component, from 0 to C-1.

Returns:

The root of the tree structure.

getCbULX

public int getCbULX()

Returns the horizontal code-block partition origin. Allowable values are 0 and 1, nothing else.

Specified by:

getCbULX in interface InvWTData

getCbULY

public int getCbULY()

Returns the vertical code-block partition origin. Allowable values are 0 and 1, nothing else.

Specified by:

getCbULY in interface InvWTData

getParameterInfo

public static String[][] getParameterInfo()

Returns the parameters that are used in this class and implementing classes. It returns a 2D String array. Each of the 1D arrays is for a different option, and they have 3 elements. The first element is the option name, the second one is the synopsis and the third one is a long description of what the parameter is. The synopsis or description may be 'null', in which case it is assumed that there is no synopsis or description of the option, respectively. Null may be returned if no options are supported.

Returns:

the options name, their synopsis and their explanation, or null if no options are supported.