jj2000.j2k.entropy.decoder.EntropyDecoder Maven / Gradle / Ivy
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/*
* $RCSfile: EntropyDecoder.java,v $
* $Revision: 1.1 $
* $Date: 2005/02/11 05:02:06 $
* $State: Exp $
*
* Class: EntropyDecoder
*
* Description: The abstract class for all entropy decoders.
*
*
*
* COPYRIGHT:
*
* This software module was originally developed by Raphaël Grosbois and
* Diego Santa Cruz (Swiss Federal Institute of Technology-EPFL); Joel
* Askelöf (Ericsson Radio Systems AB); and Bertrand Berthelot, David
* Bouchard, Félix Henry, Gerard Mozelle and Patrice Onno (Canon Research
* Centre France S.A) in the course of development of the JPEG2000
* standard as specified by ISO/IEC 15444 (JPEG 2000 Standard). This
* software module is an implementation of a part of the JPEG 2000
* Standard. Swiss Federal Institute of Technology-EPFL, Ericsson Radio
* Systems AB and Canon Research Centre France S.A (collectively JJ2000
* Partners) agree not to assert against ISO/IEC and users of the JPEG
* 2000 Standard (Users) any of their rights under the copyright, not
* including other intellectual property rights, for this software module
* with respect to the usage by ISO/IEC and Users of this software module
* or modifications thereof for use in hardware or software products
* claiming conformance to the JPEG 2000 Standard. Those intending to use
* this software module in hardware or software products are advised that
* their use may infringe existing patents. The original developers of
* this software module, JJ2000 Partners and ISO/IEC assume no liability
* for use of this software module or modifications thereof. No license
* or right to this software module is granted for non JPEG 2000 Standard
* conforming products. JJ2000 Partners have full right to use this
* software module for his/her own purpose, assign or donate this
* software module to any third party and to inhibit third parties from
* using this software module for non JPEG 2000 Standard conforming
* products. This copyright notice must be included in all copies or
* derivative works of this software module.
*
* Copyright (c) 1999/2000 JJ2000 Partners.
* */
package jj2000.j2k.entropy.decoder;
import jj2000.j2k.quantization.dequantizer.CBlkQuantDataSrcDec;
import jj2000.j2k.wavelet.synthesis.MultiResImgData;
import jj2000.j2k.wavelet.synthesis.MultiResImgDataAdapter;
import jj2000.j2k.wavelet.synthesis.SubbandSyn;
/**
* 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 MultiResImgData
* @see MultiResImgDataAdapter
* */
public abstract class EntropyDecoder extends MultiResImgDataAdapter
implements CBlkQuantDataSrcDec {
/** The prefix for entropy decoder optiojns: 'C' */
public final static char OPT_PREFIX = 'C';
/** The list of parameters that is accepted by the entropy
* decoders. They start with 'C'. */
private final static String [][] pinfo = {
{"Cverber", "[true|false]",
"Specifies if the entropy decoder should be verbose about detected "+
"errors. If 'true' a message is printed whenever an error is detected.",
"true"},
{"Cer", "[true|false]",
"Specifies if error detection should be performed by the entropy "+
"decoder engine. If errors are detected they will be concealed and "+
"the resulting distortion will be less important. Note that errors "+
"can only be detected if the encoder that generated the data "+
"included error resilience information.", "true"},
};
/** The bit stream transport from where to get the compressed data
* (the source) */
protected CodedCBlkDataSrcDec src;
/**
* Initializes the source of compressed data.
*
* @param src From where to obtain the compressed data.
* */
public EntropyDecoder(CodedCBlkDataSrcDec src) {
super(src);
this.src = src;
}
/**
* 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.
*
* @param t The index of the tile, from 0 to T-1.
*
* @param c The index of the component, from 0 to C-1.
*
* @return The root of the tree structure.
* */
public SubbandSyn getSynSubbandTree(int t,int c) {
return src.getSynSubbandTree(t,c);
}
/**
* Returns the horizontal code-block partition origin. Allowable values
* are 0 and 1, nothing else.
* */
public int getCbULX() {
return src.getCbULX();
}
/**
* Returns the vertical code-block partition origin. Allowable values are
* 0 and 1, nothing else.
* */
public int getCbULY() {
return src.getCbULY();
}
/**
* 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.
*
* @return the options name, their synopsis and their explanation,
* or null if no options are supported.
* */
public static String[][] getParameterInfo() {
return pinfo;
}
}