001/*
002 * $RCSfile: SynWTFilterSpec.java,v $
003 * $Revision: 1.1 $
004 * $Date: 2005/02/11 05:02:34 $
005 * $State: Exp $
006 *
007 * Class:                   SynWTFilterSpec
008 *
009 * Description:             Synthesis filters specification
010 *
011 *
012 *
013 * COPYRIGHT:
014 *
015 * This software module was originally developed by Raphaël Grosbois and
016 * Diego Santa Cruz (Swiss Federal Institute of Technology-EPFL); Joel
017 * Askelöf (Ericsson Radio Systems AB); and Bertrand Berthelot, David
018 * Bouchard, Félix Henry, Gerard Mozelle and Patrice Onno (Canon Research
019 * Centre France S.A) in the course of development of the JPEG2000
020 * standard as specified by ISO/IEC 15444 (JPEG 2000 Standard). This
021 * software module is an implementation of a part of the JPEG 2000
022 * Standard. Swiss Federal Institute of Technology-EPFL, Ericsson Radio
023 * Systems AB and Canon Research Centre France S.A (collectively JJ2000
024 * Partners) agree not to assert against ISO/IEC and users of the JPEG
025 * 2000 Standard (Users) any of their rights under the copyright, not
026 * including other intellectual property rights, for this software module
027 * with respect to the usage by ISO/IEC and Users of this software module
028 * or modifications thereof for use in hardware or software products
029 * claiming conformance to the JPEG 2000 Standard. Those intending to use
030 * this software module in hardware or software products are advised that
031 * their use may infringe existing patents. The original developers of
032 * this software module, JJ2000 Partners and ISO/IEC assume no liability
033 * for use of this software module or modifications thereof. No license
034 * or right to this software module is granted for non JPEG 2000 Standard
035 * conforming products. JJ2000 Partners have full right to use this
036 * software module for his/her own purpose, assign or donate this
037 * software module to any third party and to inhibit third parties from
038 * using this software module for non JPEG 2000 Standard conforming
039 * products. This copyright notice must be included in all copies or
040 * derivative works of this software module.
041 *
042 * Copyright (c) 1999/2000 JJ2000 Partners.
043 *
044 *
045 *
046 */
047package jj2000.j2k.wavelet.synthesis;
048
049import jj2000.j2k.ModuleSpec;
050
051/**
052 * This class extends ModuleSpec class for synthesis filters
053 * specification holding purpose.
054 *
055 * @see ModuleSpec
056 *
057 * */
058public class SynWTFilterSpec extends ModuleSpec {
059
060    /**
061     * Constructs a new 'SynWTFilterSpec' for the specified number of
062     * components and tiles.
063     *
064     * @param nt The number of tiles
065     *
066     * @param nc The number of components
067     *
068     * @param type the type of the specification module i.e. tile specific,
069     * component specific or both.
070     *
071     * */
072    public SynWTFilterSpec(int nt, int nc, byte type){
073        super(nt, nc, type);
074    }
075
076    /**
077     * Returns the data type used by the filters in this object, as defined in
078     * the 'DataBlk' interface for specified tile-component.
079     *
080     * @param t Tile index
081     *
082     * @param c Component index
083     *
084     * @return The data type of the filters in this object
085     *
086     * @see jj2000.j2k.image.DataBlk
087     *
088     * */
089    public int getWTDataType(int t,int c){
090        SynWTFilter[][] an = (SynWTFilter[][])getSpec(t,c);
091        return an[0][0].getDataType();
092    }
093
094    /**
095     * Returns the horizontal analysis filters to be used in component 'n' and
096     * tile 't'.
097     *
098     * <P>The horizontal analysis filters are returned in an array of
099     * SynWTFilter. Each element contains the horizontal filter for each
100     * resolution level starting with resolution level 1 (i.e. the analysis
101     * filter to go from resolution level 1 to resolution level 0). If there
102     * are less elements than the maximum resolution level, then the last
103     * element is assumed to be repeated.
104     *
105     * @param t The tile index, in raster scan order
106     *
107     * @param c The component index.
108     *
109     * @return The array of horizontal analysis filters for component 'n' and
110     * tile 't'.
111     *
112     *
113     * */
114    public SynWTFilter[] getHFilters(int t, int c) {
115        SynWTFilter[][] an = (SynWTFilter[][])getSpec(t,c);
116        return an[0];
117    }
118
119    /**
120     * Returns the vertical analysis filters to be used in component 'n' and
121     * tile 't'.
122     *
123     * <P>The vertical analysis filters are returned in an array of
124     * SynWTFilter. Each element contains the vertical filter for each
125     * resolution level starting with resolution level 1 (i.e. the analysis
126     * filter to go from resolution level 1 to resolution level 0). If there
127     * are less elements than the maximum resolution level, then the last
128     * element is assumed to be repeated.
129     *
130     * @param t The tile index, in raster scan order
131     *
132     * @param c The component index.
133     *
134     * @return The array of horizontal analysis filters for component 'n' and
135     * tile 't'.
136     *
137     *
138     * */
139    public SynWTFilter[] getVFilters(int t,int c) {
140        SynWTFilter[][] an = (SynWTFilter[][])getSpec(t,c);
141        return an[1];
142    }
143
144    /** Debugging method */
145    public String toString(){
146        String str = "";
147        SynWTFilter[][] an;
148
149        str += "nTiles="+nTiles+"\nnComp="+nComp+"\n\n";
150
151        for(int t=0; t<nTiles; t++){
152            for(int c=0; c<nComp; c++){
153                an = (SynWTFilter[][])getSpec(t,c);
154
155                str += "(t:"+t+",c:"+c+")\n";
156
157                // Horizontal filters
158                str += "\tH:";
159                for(int i=0; i<an[0].length; i++)
160                    str += " "+an[0][i];
161                // Horizontal filters
162                str += "\n\tV:";
163                for(int i=0; i<an[1].length; i++)
164                    str += " "+an[1][i];
165                str += "\n";
166            }
167        }
168
169        return str;
170    }
171
172    /**
173     * Check the reversibility of filters contained is the given
174     * tile-component.
175     *
176     * @param t The index of the tile
177     *
178     * @param c The index of the component
179     *
180     */
181    public boolean isReversible(int t,int c){
182        // Note: no need to buffer the result since this method is
183        // normally called once per tile-component.
184        SynWTFilter[]
185            hfilter = getHFilters(t,c),
186            vfilter = getVFilters(t,c);
187
188        // As soon as a filter is not reversible, false can be returned
189        for(int i=hfilter.length-1; i>=0; i--)
190            if(!hfilter[i].isReversible() || !vfilter[i].isReversible())
191                return false;
192        return true;
193    }
194}