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.util.*;
050import jj2000.j2k.*;
051
052import java.util.*;
053
054/**
055 * This class extends ModuleSpec class for synthesis filters
056 * specification holding purpose.
057 *
058 * @see ModuleSpec
059 *
060 * */
061public class SynWTFilterSpec extends ModuleSpec {
062
063    /**
064     * Constructs a new 'SynWTFilterSpec' for the specified number of
065     * components and tiles.
066     *
067     * @param nt The number of tiles
068     *
069     * @param nc The number of components
070     *
071     * @param type the type of the specification module i.e. tile specific,
072     * component specific or both.
073     *
074     * */
075    public SynWTFilterSpec(int nt, int nc, byte type){
076        super(nt, nc, type);
077    }
078
079    /**
080     * Returns the data type used by the filters in this object, as defined in
081     * the 'DataBlk' interface for specified tile-component.
082     *
083     * @param t Tile index
084     *
085     * @param c Component index
086     *
087     * @return The data type of the filters in this object
088     *
089     * @see jj2000.j2k.image.DataBlk
090     *
091     * */
092    public int getWTDataType(int t,int c){
093        SynWTFilter[][] an = (SynWTFilter[][])getSpec(t,c);
094        return an[0][0].getDataType();
095    }
096
097    /**
098     * Returns the horizontal analysis filters to be used in component 'n' and
099     * tile 't'.
100     *
101     * <P>The horizontal analysis filters are returned in an array of
102     * SynWTFilter. Each element contains the horizontal filter for each
103     * resolution level starting with resolution level 1 (i.e. the analysis
104     * filter to go from resolution level 1 to resolution level 0). If there
105     * are less elements than the maximum resolution level, then the last
106     * element is assumed to be repeated.
107     *
108     * @param t The tile index, in raster scan order
109     *
110     * @param c The component index.
111     *
112     * @return The array of horizontal analysis filters for component 'n' and
113     * tile 't'.
114     *
115     *
116     * */
117    public SynWTFilter[] getHFilters(int t, int c) {
118        SynWTFilter[][] an = (SynWTFilter[][])getSpec(t,c);
119        return an[0];
120    }
121
122    /**
123     * Returns the vertical analysis filters to be used in component 'n' and
124     * tile 't'.
125     *
126     * <P>The vertical analysis filters are returned in an array of
127     * SynWTFilter. Each element contains the vertical filter for each
128     * resolution level starting with resolution level 1 (i.e. the analysis
129     * filter to go from resolution level 1 to resolution level 0). If there
130     * are less elements than the maximum resolution level, then the last
131     * element is assumed to be repeated.
132     *
133     * @param t The tile index, in raster scan order
134     *
135     * @param c The component index.
136     *
137     * @return The array of horizontal analysis filters for component 'n' and
138     * tile 't'.
139     *
140     *
141     * */
142    public SynWTFilter[] getVFilters(int t,int c) {
143        SynWTFilter[][] an = (SynWTFilter[][])getSpec(t,c);
144        return an[1];
145    }
146
147    /** Debugging method */
148    public String toString(){
149        String str = "";
150        SynWTFilter[][] an;
151
152        str += "nTiles="+nTiles+"\nnComp="+nComp+"\n\n";
153
154        for(int t=0; t<nTiles; t++){
155            for(int c=0; c<nComp; c++){
156                an = (SynWTFilter[][])getSpec(t,c);
157
158                str += "(t:"+t+",c:"+c+")\n";
159
160                // Horizontal filters
161                str += "\tH:";
162                for(int i=0; i<an[0].length; i++)
163                    str += " "+an[0][i];
164                // Horizontal filters
165                str += "\n\tV:";
166                for(int i=0; i<an[1].length; i++)
167                    str += " "+an[1][i];
168                str += "\n";
169            }
170        }
171
172        return str;
173    }
174
175    /**
176     * Check the reversibility of filters contained is the given
177     * tile-component.
178     *
179     * @param t The index of the tile
180     *
181     * @param c The index of the component
182     *
183     */
184    public boolean isReversible(int t,int c){
185        // Note: no need to buffer the result since this method is
186        // normally called once per tile-component.
187        SynWTFilter[]
188            hfilter = getHFilters(t,c),
189            vfilter = getVFilters(t,c);
190
191        // As soon as a filter is not reversible, false can be returned
192        for(int i=hfilter.length-1; i>=0; i--)
193            if(!hfilter[i].isReversible() || !vfilter[i].isReversible())
194                return false;
195        return true;
196    }
197}