forwwtfull.java

jpeg2000编解码

/*
 * CVS identifier:
 *
 * $Id: ForwWTFull.java,v 1.1.1.1 2002/07/22 09:26:54 grosbois Exp $
 *
 * Class:                   ForwWTFull
 *
 * Description:             This class implements the full page
 *                          forward wavelet transform for both integer
 *                          and floating point implementations.
 *
 *
 *
 * COPYRIGHT:
 * 
 * This software module was originally developed by Rapha雔 Grosbois and
 * Diego Santa Cruz (Swiss Federal Institute of Technology-EPFL); Joel
 * Askel鰂 (Ericsson Radio Systems AB); and Bertrand Berthelot, David
 * Bouchard, F閘ix 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.wavelet.analysis;

import jj2000.j2k.codestream.*;
import jj2000.j2k.entropy.*;
import jj2000.j2k.wavelet.*;
import jj2000.j2k.encoder.*;
import jj2000.j2k.image.*;
import jj2000.j2k.util.*;
import jj2000.j2k.*;

/**
 * This class implements the ForwardWT abstract class with the full-page
 * approach to be used either with integer or floating-point filters
 *
 * @see ForwardWT
 * */
public class ForwWTFull extends ForwardWT {

    /** Boolean to know if one are currently dealing with int or float data.*/
    private boolean intData;
    
    /**
     * The subband trees of each tile-component. The array is allocated by the
     * constructor of this class and updated by the getAnSubbandTree() method
     * when needed. The first index is the tile index (in lexicographical
     * order) and the second index is the component index.
     *
     * <p>The subband tree for a component in the current tile is created on
     * the first call to getAnSubbandTree() for that component, in the current
     * tile. Before that, the element in 'subbTrees' is null.</p>
     * */
    private SubbandAn subbTrees[][];

    /** The source of image data */
    private BlkImgDataSrc src;
    
    /** The horizontal coordinate of the code-block partition origin on the
        reference grid */
    private int cb0x;

    /** The vertical coordinate of the code-block partition on the reference
        grid */
    private int cb0y;

    /** The number of decomposition levels specification */
    private IntegerSpec dls;

    /** Wavelet filters for all components and tiles */
    private AnWTFilterSpec filters;
     
    /** The code-block size specifications */
    private CBlkSizeSpec cblks;

    /** The precinct partition specifications */
    private PrecinctSizeSpec pss;
    
    /** Block storing the full band decomposition for each component. */
    private DataBlk decomposedComps[];
    
    /** The horizontal index of the last "sent" code-block in the current
     * subband in each component. It should be -1 if none have been sent yet.
     * */
    private int lastn[];

    /** The vertical index of the last "sent" code-block in the current
     * subband in each component. It should be 0 if none have been sent yet.
     * */
    private int lastm[];
    
    /** The subband being dealt with in each component */
    SubbandAn currentSubband[];
    
    /**  Cache  object   to  avoid  excessive  allocation/desallocation.  This
     * variable makes the class inheritently thread unsafe. */
    Coord ncblks;

    /**
     * Initializes this object with the given source of image data and with
     * all the decompositon parameters
     *
     * @param src From where the image data should be obtained.
     *
     * @param encSpec The encoder specifications
     *
     * @param cb0x The horizontal coordinate of the code-block partition
     * origin on the reference grid.
     *
     * @param cb0y The vertical coordinate of the code-block partition origin
     * on the reference grid.
     *
     * @see ForwardWT
     * */
    public ForwWTFull(BlkImgDataSrc src,EncoderSpecs encSpec,
                      int cb0x,int cb0y) {
        super(src);
        this.src  = src;
        this.cb0x  = cb0x;
        this.cb0y  = cb0y;
        this.dls  = encSpec.dls;
	this.filters = encSpec.wfs;
        this.cblks = encSpec.cblks;
        this.pss = encSpec.pss;

	int ncomp = src.getNumComps();
	int ntiles = src.getNumTiles();

        currentSubband = new SubbandAn[ncomp];
        decomposedComps = new DataBlk[ncomp];
	subbTrees = new SubbandAn[ntiles][ncomp];
        lastn = new int[ncomp];
        lastm = new int[ncomp];
    }

    /**
     * Returns the implementation type of this wavelet transform, WT_IMPL_FULL 
     * (full-page based transform). All components return the same.
     *
     * @param c The index of the component.
     *
     * @return WT_IMPL_FULL
     * */
    public int getImplementationType(int c) {
        return WaveletTransform.WT_IMPL_FULL;
    }

    /**
     * Returns the number of decomposition levels that are applied to the LL
     * band, in the specified tile-component. A value of 0 means that no
     * wavelet transform is applied.
     *
     * @param t The tile index
     *
     * @param c The index of the component.
     *
     * @return The number of decompositions applied to the LL band (0 for no
     * wavelet transform).
     * */
    public int getDecompLevels(int t,int c) {
        return ((Integer)dls.getTileCompVal(t,c)).intValue();
    }

    /**
     * Returns the wavelet tree decomposition. Actually JPEG 2000 part 1 only
     * supports WT_DECOMP_DYADIC decomposition.
     *
     * @param t The tile-index
     *
     * @param c The index of the component.
     *
     * @return The wavelet decomposition.
     * */
    public int getDecomp(int t,int c) {
        return WT_DECOMP_DYADIC;
    }

    /**
     * Returns the horizontal analysis wavelet filters used in each level, for
     * the specified component and tile. The first element in the array is the
     * filter used to obtain the lowest resolution (resolution level 0)
     * subbands (i.e. lowest frequency LL subband), the second element is the
     * one used to generate the resolution level 1 subbands, and so on. If
     * there are less elements in the array than the number of resolution
     * levels, then the last one is assumed to repeat itself.
     *
     * <p>The returned filters are applicable only to the specified component
     * and in the current tile.</p>
     *
     * <p>The resolution level of a subband is the resolution level to which a
     * subband contributes, which is different from its decomposition
     * level.</p>
     *
     * @param t The index of the tile for which to return the filters.
     *
     * @param c The index of the component for which to return the filters.
     *
     * @return The horizontal analysis wavelet filters used in each level.
     * */
    public AnWTFilter[] getHorAnWaveletFilters(int t,int c) {
        return filters.getHFilters(t,c);
    }

    /**
     * Returns the vertical analysis wavelet filters used in each level, for
     * the specified component and tile. The first element in the array is the
     * filter used to obtain the lowest resolution (resolution level 0)
     * subbands (i.e. lowest frequency LL subband), the second element is the
     * one used to generate the resolution level 1 subbands, and so on. If
     * there are less elements in the array than the number of resolution
     * levels, then the last one is assumed to repeat itself.
     *
     * <p>The returned filters are applicable only to the specified component
     * and in the current tile.</p>
     *
     * <p>The resolution level of a subband is the resolution level to which a
     * subband contributes, which is different from its decomposition
     * level.</p>
     *
     * @param t The index of the tile for which to return the filters.
     *
     * @param c The index of the component for which to return the filters.
     *
     * @return The vertical analysis wavelet filters used in each level.
     * */
    public AnWTFilter[] getVertAnWaveletFilters(int t,int c) {
        return filters.getVFilters(t,c);
    }

    /**
     * Returns the reversibility of the wavelet transform for the specified
     * component and tile. A wavelet transform is reversible when it is
     * suitable for lossless and lossy-to-lossless compression.
     *
     * @param t The index of the tile.
     *
     * @param c The index of the component.
     *
     * @return true is the wavelet transform is reversible, false if not.
     * */
    public boolean isReversible(int t,int c) {
	return filters.isReversible(t,c);
    }
    
    /**
     * Returns the horizontal offset of the code-block partition. Allowable
     * values are 0 and 1, nothing else.
     * */
    public int getCbULX() {
        return cb0x;
    }

    /**
     * Returns the vertical offset of the code-block partition. Allowable
     * values are 0 and 1, nothing else.
     * */
    public int getCbULY() {
        return cb0y;
    }

    /**
     * Returns the position of the fixed point in the specified
     * component. This is the position of the least significant integral
     * (i.e. non-fractional) bit, which is equivalent to the number of
     * fractional bits. For instance, for fixed-point values with 2 fractional
     * bits, 2 is returned. For floating-point data this value does not apply
     * and 0 should be returned. Position 0 is the position of the least
     * significant bit in the data.
     *
     * @param c The index of the component.
     *
     * @return The position of the fixed-point, which is the same as the
     * number of fractional bits. For floating-point data 0 is returned.
     * */
    public int getFixedPoint(int c) {
        return src.getFixedPoint(c);
    }
    
    /**
     * Returns the next code-block in the current tile for the specified
     * component. The order in which code-blocks are returned is not
     * specified. However each code-block is returned only once and all
     * code-blocks will be returned if the method is called 'N' times, where
     * 'N' is the number of code-blocks in the tile. After all the code-blocks
     * have been returned for the current tile calls to this method will
     * return 'null'.
     *
     * <p>When changing the current tile (through 'setTile()' or 'nextTile()')
     * this method will always return the first code-block, as if this method
     * was never called before for the new current tile.</p>
     *
     * <p>The data returned by this method is the data in the internal buffer
     * of this object, and thus can not be modified by the caller. The
     * 'offset' and 'scanw' of the returned data have, in general, some
     * non-zero value. The 'magbits' of the returned data is not set by this
     * method and should be ignored. See the 'CBlkWTData' class.</p>
     *
     * <p>The 'ulx' and 'uly' members of the returned 'CBlkWTData' object
     * contain the coordinates of the top-left corner of the block, with
     * respect to the tile, not the subband.</p>
     *
     * @param c The component for which to return the next code-block.
     *
     * @param cblk If non-null this object will be used to return the new
     * code-block. If null a new one will be allocated and returned.
     *
     * @return The next code-block in the current tile for component 'n', or
     * null if all code-blocks for the current tile have been returned.
     *
     * @see CBlkWTData
     * */
    public CBlkWTData getNextInternCodeBlock(int c, CBlkWTData cblk) {
        int cbm,cbn,cn,cm;
        int acb0x, acb0y;
        SubbandAn sb;
	intData = (filters.getWTDataType(tIdx,c)==DataBlk.TYPE_INT);

        //If the source image has not been decomposed 
        if(decomposedComps[c]==null) {
            int k,w,h;
            DataBlk bufblk;
            Object dst_data;
	    
            w = getTileCompWidth(tIdx,c);
            h = getTileCompHeight(tIdx,c);
	    
            //Get the source image data
            if(intData) {