exit(-1);    }    /* read magic word for format of file */    fscanf(fp,"%s\n",file_type);    j = strcmp(file_type,"pixel");    if(j != 0){        printf("not link data file - aborting\n");        exit(-1);    }    for (j=0;j<height;j++)        for (i=0;i<width;i++)            image_length[j][i] = 0;    do {        read_link_data(fp,&endoffile);        store_length();        combine_clutter();    } while (!endoffile);    fclose(fp);    /* ++++++++++++++++++ SECOND PASS ++++++++++++++++++ */    /* propagate distance etc */    j = 0;    do {        j++;        printf("iteration %d\n",j);        change = FALSE;        /* forward pass */        for (y = 1; y < height-1; y++) {            for (x = 1; x < width-1; x++) {                prev_measure = (double) (image_dist[x][y]+K) /                               (double) (((unsigned int)image_mag[x][y]+K) *                                          (image_length[x][y]+K) *                                          (clutter_area[x][y]+K));                for (i = 0; i < MASK_SIZE; i++) {                    xn = x + x_offset[i]; yn = y + y_offset[i];                    d[i] = image_dist[xn][yn] + i_offset[i];                    m[i] = (unsigned char)image_mag[xn][yn];                    l[i] = image_length[xn][yn];                    c[i] = clutter_area[xn][yn];                }                min_loc = 0;                min_measure = (double) (d[0]+K) /                              (double) ((m[0]+K) * (l[0]+K) * (c[0]+K));                for (i = 1; i < MASK_SIZE; i++) {                    measure = (double) (d[i]+K) /                              (double) ((m[i]+K) * (l[i]+K) * (c[i]+K));                    if (measure < min_measure) {                        min_measure = measure;                        min_loc = i;                    }                }                image_dist[x][y] = d[min_loc];                image_mag[x][y] = m[min_loc];                image_length[x][y] = l[min_loc];                clutter_area[x][y] = c[min_loc];                if (prev_measure != min_measure)                    change = TRUE;            }        }        /* backward pass */        for (y = height-2; y >= 1; y--) {            for (x = width-2; x >= 1; x--) {                prev_measure = (double) (image_dist[x][y]+K) /                               (double) (((unsigned int)image_mag[x][y]+K) *                                          (image_length[x][y]+K) *                                          (clutter_area[x][y]+K));                for (i = 0; i < MASK_SIZE; i++) {                    xn = x - x_offset[i]; yn = y - y_offset[i];                    d[i] = image_dist[xn][yn] + i_offset[i];                    m[i] = (unsigned char)image_mag[xn][yn];                    l[i] = image_length[xn][yn];                    c[i] = clutter_area[xn][yn];                }                min_loc = 0;                min_measure = (double) (d[0]+K) /                              (double) ((m[0]+K) * (l[0]+K) * (c[0]+K));                for (i = 1; i < MASK_SIZE; i++) {                    measure = (double) (d[i]+K) /                              (double) ((m[i]+K) * (l[i]+K) * (c[i]+K));                    if (measure < min_measure) {                        min_measure = measure;                        min_loc = i;                    }                }                image_dist[x][y] = d[min_loc];                image_mag[x][y] = m[min_loc];                image_length[x][y] = l[min_loc];                clutter_area[x][y] = c[min_loc];                if (prev_measure != min_measure)                    change = TRUE;            }        }    } while (change && j < max_iter);    /* calculate measure values */    for (y = 1; y < height-1; y++) {        for (x = 1; x < width-1; x++) {            image_measure[x][y] = (double) (image_dist[x][y]+K) /                                 ((double) ((unsigned int)image_mag[x][y]+K) *                                            (image_length[x][y]+K) *                                            (clutter_area[x][y]+K));        }    }    /* rescale */    max_val = image_measure[1][1];    for (y = 1; y < height-1; y++)        for (x = 1; x < width-1; x++)            if (image_measure[x][y] > max_val)                max_val = image_measure[x][y];    for (y = 1; y < height-1; y++)        for (x = 1; x < width-1; x++)            tmp[x][y] = (unsigned char)(image_measure[x][y] * 255 / max_val);    /* reset borders */    for (y = 0; y < height; y++)        tmp[0][y] = tmp[width-1][y] = 255;    for (x = 0; x < width; x++)        tmp[x][0] = tmp[x][height-1] = 255;    write_pgm(tmp,outfile,width,height);}store_length(){    int i;    if (cancel_length)        /* arbitrary constant value */        for (i = 0; i < no_pixels; i++)            image_length[x[i]][y[i]] = 100;    else        for (i = 0; i < no_pixels; i++)            image_length[x[i]][y[i]] = no_pixels;}store_curve_labels(label){    int i;    for (i = 0; i < no_pixels; i++)        curve_labels[x[i]][y[i]] = label;}combine_clutter(){    int i;    float total = 0;    for (i = 0; i < no_pixels; i++)        total += clutter_area[x[i]][y[i]];    for (i = 0; i < no_pixels; i++)        clutter_area[x[i]][y[i]] = total;}read_link_data(fp,endoffile)FILE *fp;int *endoffile;{    char dumstring[50];    int j;    fscanf(fp,"%s %d\n",dumstring,&j);    j = -1;    do{       j++;       fscanf(fp,"%d %d\n",&x[j],&y[j]);    } while(x[j] != -1);    *endoffile = (y[j] == -1);    no_pixels = j;}/* save coordinates of nearest edge point to each point in text file */save_ascii(filename)char filename[];{    int x,y;    FILE *fp;    double dx,dy;    if ((fp=fopen(filename,"w")) == NULL) {        printf("cant open file: %s\n",filename);        exit(-1);    }    for (y = 1; y < height-1; y++)        for (x = 1; x < width-1; x++) {            dx = x - X[x][y];            dy = y - Y[x][y];            fprintf(fp,"%d %d ",x,y);            fprintf(fp,"%d %d\n",X[x][y],Y[x][y]);        }    fclose(fp);}/* save coordinates of nearest edge point to each point in 2 images */save_xy(fnx,fny)char fnx[],fny[];{    int x,y;    /* reset borders */    for (y = 0; y < height; y++)        tmp[0][y] = tmp[width-1][y] = 0;    for (x = 0; x < width; x++)        tmp[x][0] = tmp[x][height-1] = 0;    for (y = 1; y < height-1; y++)        for (x = 1; x < width-1; x++)            tmp[x][y] = X[x][y];    write_pgm(tmp,fnx,width,height);    for (y = 1; y < height-1; y++)        for (x = 1; x < width-1; x++)            tmp[x][y] = Y[x][y];    write_pgm(tmp,fny,width,height);}/* save image of Voronoi cell labels from each point */save_voronoi1(filename)char filename[];{    static int label[MAX_SIZE][MAX_SIZE];    static int hist[MAX_SIZE*MAX_SIZE][2];    int x,y;    int i;    int count;    /* create unique label for each Voronoi cell */    for (y = 1; y < height-1; y++)        for (x = 1; x < width-1; x++)            label[x][y] = X[x][y] + Y[x][y] * MAX_SIZE;    for (i = 0; i < MAX_SIZE*MAX_SIZE; i++)        hist[i][0] = hist[i][1] = 0;    for (x = 0; x < width; x++)        for (y = 0; y < height; y++)            hist[label[x][y]][0]++;    count = 0;    for (i = 0; i < MAX_SIZE*MAX_SIZE; i++) {        if (hist[i][0] > 0) {            hist[i][1] = count;            count++;        }    }    printf("number of Voronoi cells: %d\n",count);    for (x = 0; x < width; x++)        for (y = 0; y < height; y++)            tmp[x][y] = (unsigned char) hist[label[x][y]][1];    /* reset borders */    for (y = 0; y < height; y++)        tmp[0][y] = tmp[width-1][y] = 0;    for (x = 0; x < width; x++)        tmp[x][0] = tmp[x][height-1] = 0;    write_pgm(tmp,filename,width,height);}/* save image of Voronoi cell labels from each curve */save_voronoi2(pixel_file,voronoi_file)char *pixel_file,*voronoi_file;{    int x,y;    int i,j;    int count;    FILE *fp;    char file_type[50];    int endoffile;    /* read and pixel lists and store lengths */    if ((fp=fopen(pixel_file,"r")) == NULL) {        printf("cant open pixel file: %s\n",pixel_file);        exit(-1);    }    /* read magic word for format of file */    fscanf(fp,"%s\n",file_type);    j = strcmp(file_type,"pixel");    if (j != 0){        printf("not link data file - aborting\n");        exit(-1);    }    for (j = 0; j < height; j++)        for (i = 0; i < width; i++)            curve_labels[j][i] = 0;    count = 1;    do {        read_link_data(fp,&endoffile);        store_curve_labels(count);        count++;    } while (!endoffile);    fclose(fp);    if (count > 255) {        fprintf(stderr,"ERROR: too many pixel lists (%d) to store as Voronoi labels\n",count);        return;    }    /* store curve label for each Voronoi cell */    for (y = 1; y < height-1; y++)        for (x = 1; x < width-1; x++)            tmp[x][y] = (unsigned char) curve_labels[X[x][y]][Y[x][y]];    /* reset borders */    for (y = 0; y < height; y++)        tmp[0][y] = tmp[width-1][y] = 0;    for (x = 0; x < width; x++)        tmp[x][0] = tmp[x][height-1] = 0;    write_pgm(tmp,voronoi_file,width,height);}/* save image of clutter values at each curve */save_clutter(pixel_file,clutter_file)char *pixel_file,*clutter_file;{    int xx,yy;    int i,j;    FILE *fp;    char file_type[50];    int endoffile;    double avg,max_val;    /* read and pixel lists and store lengths */    if ((fp=fopen(pixel_file,"r")) == NULL) {        printf("cant open pixel file: %s\n",pixel_file);        exit(-1);    }    /* read magic word for format of file */    fscanf(fp,"%s\n",file_type);    j = strcmp(file_type,"pixel");    if (j != 0){        printf("not link data file - aborting\n");        exit(-1);    }    for (yy = 0; yy < height; yy++)       for (xx = 0; xx < width; xx++)          tmp2[xx][yy] = 0;    max_val = 0;    do {        read_link_data(fp,&endoffile);        avg = 0;        for (i = 0; i < no_pixels; i++)            avg += clutter_area[x[i]][y[i]];        avg /= (double)no_pixels;        for (i = 0; i < no_pixels; i++)            tmp2[x[i]][y[i]] = avg;        if (avg >  max_val)            max_val = avg;    } while (!endoffile);    fclose(fp);    printf("rescaling from maximum clutter value: %f\n",max_val);    for (yy = 0; yy < height; yy++)       for (xx = 0; xx < width; xx++)          tmp[xx][yy] = (unsigned char)(tmp2[xx][yy] * 255.0 / max_val);    write_pgm(tmp,clutter_file,width,height);}options(progname)char *progname;{    printf("usage: %s [options]\n",progname);    printf("     -a file    save coords of nearest edge as ASCII file\n");    printf("     -b file    binary edge map (optional)\n");    printf("     -e file    edge magnitude map\n");    printf("     -o file    output distance map\n");    printf("     -p file    pixel lists\n");    printf("     -n int     maximum number of iterations (default: %d)\n",max_iter);    printf("     -v file    save Voronoi diagram from 1st pass\n");    printf("     -c file    save edge clutter map from 1st pass\n");    printf("     -L         do NOT use length attribute\n");    exit(-1);}