pi.c

关于JPEG2000压缩标准的模板程序的内容,是我们导师给的,据说是国外的版本.

/*
 * Copyright (c) 2001-2002, David Janssens
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS `AS IS'
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#include "pi.h"
#include "int.h"
#include <stdlib.h>

/// <summary>
/// Create a packet iterator.  
/// </summary>
pi_iterator_t *pi_create(j2k_image_t *img, j2k_cp_t *cp, int tileno) {
    int p, q;
    int compno, resno;
    int maxres=0;
    pi_iterator_t *pi;
    j2k_tcp_t *tcp;
    j2k_tccp_t *tccp;
    tcp=&cp->tcps[tileno];
    pi=(pi_iterator_t*)malloc(sizeof(pi_iterator_t));
    p=tileno%cp->tw;
    q=tileno/cp->tw;
    pi->tx0=int_max(cp->tx0+p*cp->tdx, img->x0);
    pi->ty0=int_max(cp->ty0+q*cp->tdy, img->y0);
    pi->tx1=int_min(cp->tx0+(p+1)*cp->tdx, img->x1);
    pi->ty1=int_min(cp->ty0+(q+1)*cp->tdy, img->y1);
    pi->numcomps=img->numcomps;
    pi->comps=(pi_comp_t*)malloc(img->numcomps*sizeof(pi_comp_t));
    for (compno=0; compno<pi->numcomps; compno++) {
        int tcx0, tcy0, tcx1, tcy1;
        pi_comp_t *comp=&pi->comps[compno];
        tccp=&tcp->tccps[compno];
        comp->dx=img->comps[compno].dx;
        comp->dy=img->comps[compno].dy;
        comp->numresolutions=tccp->numresolutions;
        comp->resolutions=(pi_resolution_t*)malloc(comp->numresolutions*sizeof(pi_resolution_t));
        tcx0=int_ceildiv(pi->tx0, comp->dx);
        tcy0=int_ceildiv(pi->ty0, comp->dy);
        tcx1=int_ceildiv(pi->tx1, comp->dx);
        tcy1=int_ceildiv(pi->ty1, comp->dy);
        if (comp->numresolutions>maxres) {
            maxres=comp->numresolutions;
        }
        for (resno=0; resno<comp->numresolutions; resno++) {
            int levelno;
            int rx0, ry0, rx1, ry1;
            int px0, py0, px1, py1;
            pi_resolution_t *res=&comp->resolutions[resno];
            if (tccp->csty&J2K_CCP_CSTY_PRT) {
                res->pdx=tccp->prcw[resno];
                res->pdy=tccp->prch[resno];
            } else {
                res->pdx=15;
                res->pdy=15;
            }
            levelno=comp->numresolutions-1-resno;
            rx0=int_ceildivpow2(tcx0, levelno);
            ry0=int_ceildivpow2(tcy0, levelno);
            rx1=int_ceildivpow2(tcx1, levelno);
            ry1=int_ceildivpow2(tcy1, levelno);
            px0=int_floordivpow2(rx0, res->pdx)<<res->pdx;
            py0=int_floordivpow2(ry0, res->pdy)<<res->pdy;
            px1=int_ceildivpow2(rx1, res->pdx)<<res->pdx;
            py1=int_ceildivpow2(ry1, res->pdy)<<res->pdy;
            res->pw=(px1-px0)>>res->pdx;
            res->ph=(py1-py0)>>res->pdy;
        }
    }
    pi->first=1;
    pi->poc.resno0=0;
    pi->poc.compno0=0;
    pi->poc.layno1=tcp->numlayers;
    pi->poc.resno1=maxres;
    pi->poc.compno1=img->numcomps;
    pi->poc.prg=tcp->prg;
    return pi;
}

/// <summary>
/// Get next packet in layer=resolution-component-precinct order.  
/// </summary>
int pi_next_lrcp(pi_iterator_t *pi) {
    pi_comp_t *comp;
    pi_resolution_t *res;
    if (!pi->first) {
        comp=&pi->comps[pi->compno];
        res=&comp->resolutions[pi->resno];
        goto skip;
    } else {
        pi->first=0;
    }
    for (pi->layno=0; pi->layno<pi->poc.layno1; pi->layno++) {
        for (pi->resno=pi->poc.resno0; pi->resno<pi->poc.resno1; pi->resno++) {
            for (pi->compno=pi->poc.compno0; pi->compno<pi->poc.compno1; pi->compno++) {
                comp=&pi->comps[pi->compno];
                if (pi->resno>=comp->numresolutions) {
                    continue;
                }
                res=&comp->resolutions[pi->resno];
                for (pi->precno=0; pi->precno<res->pw*res->ph; pi->precno++) {
                    return 1;
skip:			;
                }
            }
        }
    }
    return 0;
}

/// <summary>
/// Get next packet in resolution-layer-component-precinct order.  
/// </summary>
int pi_next_rlcp(pi_iterator_t *pi) {
    pi_comp_t *comp;
    pi_resolution_t *res;
    if (!pi->first) {
        comp=&pi->comps[pi->compno];
        res=&comp->resolutions[pi->resno];
        goto skip;
    } else {
        pi->first=0;
    }
    for (pi->resno=pi->poc.resno0; pi->resno<pi->poc.resno1; pi->resno++) {
        for (pi->layno=0; pi->layno<pi->poc.layno1; pi->layno++) {
            for (pi->compno=pi->poc.compno0; pi->compno<pi->poc.compno1; pi->compno++) {
                comp=&pi->comps[pi->compno];
                if (pi->resno>=comp->numresolutions) {
                    continue;
                }
                res=&comp->resolutions[pi->resno];
                for (pi->precno=0; pi->precno<res->pw*res->ph; pi->precno++) {
                    return 1;
skip:				;
                }
            }
        }
    }
    return 0;
}

/// <summary>
/// Get next packet in resolution-precinct-component-layer order.  
/// </summary>
int pi_next_rpcl(pi_iterator_t *pi) {
    pi_comp_t *comp;
    pi_resolution_t *res;
    if (!pi->first) {
        goto skip;
    } else {
        int compno, resno;
        pi->first=0;
        pi->dx=0;
        pi->dy=0;
        for (compno=0; compno<pi->numcomps; compno++) {
            comp=&pi->comps[compno];
            for (resno=0; resno<comp->numresolutions; resno++) {
                int dx, dy;
                res=&comp->resolutions[resno];
                dx=comp->dx*(1<<(res->pdx+comp->numresolutions-1-resno));
                dy=comp->dy*(1<<(res->pdy+comp->numresolutions-1-resno));
                pi->dx=!pi->dx?dx:int_min(pi->dx, dx);
                pi->dy=!pi->dy?dy:int_min(pi->dy, dy);
            }
        }
    }
    for (pi->resno=pi->poc.resno0; pi->resno<pi->poc.resno1; pi->resno++) {
        for (pi->y=pi->ty0; pi->y<pi->ty1; pi->y+=pi->dy-(pi->y%pi->dy)) {
            for (pi->x=pi->tx0; pi->x<pi->tx1; pi->x+=pi->dx-(pi->x%pi->dx)) {
                for (pi->compno=pi->poc.compno0; pi->compno<pi->poc.compno1; pi->compno++) {
                    int levelno;
                    int trx0, try0;
                    int rpx, rpy;
                    int prci, prcj;
                    comp=&pi->comps[pi->compno];
                    if (pi->resno>=comp->numresolutions) {
                        continue;
                    }
                    res=&comp->resolutions[pi->resno];
                    levelno=comp->numresolutions-1-pi->resno;
                    trx0=int_ceildiv(pi->tx0, comp->dx<<levelno);
                    try0=int_ceildiv(pi->ty0, comp->dy<<levelno);
                    rpx=res->pdx+levelno;
                    rpy=res->pdy+levelno;
                    if (!(pi->x%(comp->dx<<rpx)==0||(pi->x==pi->tx0&&(trx0<<levelno)%(1<<rpx)))) {
                        continue;
                    }
                    if (!(pi->y%(comp->dy<<rpy)==0||(pi->y==pi->ty0&&(try0<<levelno)%(1<<rpx)))) {
                        continue;
                    }
                    prci=int_floordivpow2(int_ceildiv(pi->x, comp->dx<<levelno), res->pdx)-int_floordivpow2(trx0, res->pdx);
                    prcj=int_floordivpow2(int_ceildiv(pi->y, comp->dy<<levelno), res->pdy)-int_floordivpow2(try0, res->pdy);
                    pi->precno=prci+prcj*res->pw;
                    for (pi->layno=0; pi->layno<pi->poc.layno1; pi->layno++) {
                        return 1;
skip:					;
                    }
                }
            }
        }
    }
    return 0;
}

/// <summary>
/// Get next packet in precinct-component-resolution-layer order.  
/// </summary>
int pi_next_pcrl(pi_iterator_t *pi) {
    pi_comp_t *comp;
    pi_resolution_t *res;
    if (!pi->first) {
        comp=&pi->comps[pi->compno];
        goto skip;
    } else {
        int compno, resno;
        pi->first=0;
        pi->dx=0;
        pi->dy=0;
        for (compno=0; compno<pi->numcomps; compno++) {
            comp=&pi->comps[compno];
            for (resno=0; resno<comp->numresolutions; resno++) {
                int dx, dy;
                res=&comp->resolutions[resno];
                dx=comp->dx*(1<<(res->pdx+comp->numresolutions-1-resno));
                dy=comp->dy*(1<<(res->pdy+comp->numresolutions-1-resno));
                pi->dx=!pi->dx?dx:int_min(pi->dx, dx);
                pi->dy=!pi->dy?dy:int_min(pi->dy, dy);
            }
        }
    }
    for (pi->y=pi->ty0; pi->y<pi->ty1; pi->y+=pi->dy-(pi->y%pi->dy)) {
        for (pi->x=pi->tx0; pi->x<pi->tx1; pi->x+=pi->dx-(pi->x%pi->dx)) {
            for (pi->compno=pi->poc.compno0; pi->compno<pi->poc.compno1; pi->compno++) {
                comp=&pi->comps[pi->compno];
                for (pi->resno=pi->poc.resno0; pi->resno<int_min(pi->poc.resno1, comp->numresolutions); pi->resno++) {
                    int levelno;
                    int trx0, try0;
                    int rpx, rpy;
                    int prci, prcj;
                    res=&comp->resolutions[pi->resno];
                    levelno=comp->numresolutions-1-pi->resno;
                    trx0=int_ceildiv(pi->tx0, comp->dx<<levelno);
                    try0=int_ceildiv(pi->ty0, comp->dy<<levelno);
                    rpx=res->pdx+levelno;
                    rpy=res->pdy+levelno;
                    if (!(pi->x%(comp->dx<<rpx)==0||(pi->x==pi->tx0&&(trx0<<levelno)%(1<<rpx)))) {
                        continue;
                    }
                    if (!(pi->y%(comp->dy<<rpy)==0||(pi->y==pi->ty0&&(try0<<levelno)%(1<<rpx)))) {
                        continue;
                    }
                    prci=int_floordivpow2(int_ceildiv(pi->x, comp->dx<<levelno), res->pdx)-int_floordivpow2(trx0, res->pdx);
                    prcj=int_floordivpow2(int_ceildiv(pi->y, comp->dy<<levelno), res->pdy)-int_floordivpow2(try0, res->pdy);
                    pi->precno=prci+prcj*res->pw;
                    for (pi->layno=0; pi->layno<pi->poc.layno1; pi->layno++) {
                        return 1;
skip:					;
                    }
                }
            }
        }
    }
    return 0;
}

/// <summary>
/// Get next packet in component-precinct-resolution-layer order.  
/// </summary>
int pi_next_cprl(pi_iterator_t *pi) {
    pi_comp_t *comp;
    pi_resolution_t *res;
    if (!pi->first) {
        comp=&pi->comps[pi->compno];
        goto skip;
    } else {
        pi->first=0;
    }
    for (pi->compno=pi->poc.compno0; pi->compno<pi->poc.compno1; pi->compno++) {
        int resno;
        comp=&pi->comps[pi->compno];
        pi->dx=0;
        pi->dy=0;
        for (resno=0; resno<comp->numresolutions; resno++) {
            int dx, dy;
            res=&comp->resolutions[resno];
            dx=comp->dx*(1<<(res->pdx+comp->numresolutions-1-resno));
            dy=comp->dy*(1<<(res->pdy+comp->numresolutions-1-resno));
            pi->dx=!pi->dx?dx:int_min(pi->dx, dx);
            pi->dy=!pi->dy?dy:int_min(pi->dy, dy);
        }
        for (pi->y=pi->ty0; pi->y<pi->ty1; pi->y+=pi->dy-(pi->y%pi->dy)) {
            for (pi->x=pi->tx0; pi->x<pi->tx1; pi->x+=pi->dx-(pi->x%pi->dx)) {
                for (pi->resno=pi->poc.resno0; pi->resno<int_min(pi->poc.resno1, comp->numresolutions); pi->resno++) {
                    int levelno;
                    int trx0, try0;
                    int rpx, rpy;
                    int prci, prcj;
                    res=&comp->resolutions[pi->resno];
                    levelno=comp->numresolutions-1-pi->resno;
                    trx0=int_ceildiv(pi->tx0, comp->dx<<levelno);
                    try0=int_ceildiv(pi->ty0, comp->dy<<levelno);
                    rpx=res->pdx+levelno;
                    rpy=res->pdy+levelno;
                    if (!(pi->x%(comp->dx<<rpx)==0||(pi->x==pi->tx0&&(trx0<<levelno)%(1<<rpx)))) {
                        continue;
                    }
                    if (!(pi->y%(comp->dy<<rpy)==0||(pi->y==pi->ty0&&(try0<<levelno)%(1<<rpx)))) {
                        continue;
                    }
                    prci=int_floordivpow2(int_ceildiv(pi->x, comp->dx<<levelno), res->pdx)-int_floordivpow2(trx0, res->pdx);
                    prcj=int_floordivpow2(int_ceildiv(pi->y, comp->dy<<levelno), res->pdy)-int_floordivpow2(try0, res->pdy);
                    pi->precno=prci+prcj*res->pw;
                    for (pi->layno=0; pi->layno<pi->poc.layno1; pi->layno++) {
                        return 1;
skip:					;
                    }
                }
            }
        }
    }
    return 0;
}

/// <summary>
/// Get next packet.  
/// </summary>
int pi_next(pi_iterator_t *pi) {
    switch (pi->poc.prg) {
        case 0:
            return pi_next_lrcp(pi);
        case 1:
            return pi_next_rlcp(pi);
        case 2:
            return pi_next_rpcl(pi);
        case 3:
            return pi_next_pcrl(pi);
        case 4:
            return pi_next_cprl(pi);
    }
	return 0;
}