/* * Reads in an image and then links adjacent pixels to forms lists which it * then stores in a file. An improved version of link.c adaptef from link.pas * as run on the Viglen PC To save memory, writes to a file each pixel as it * is found. erases pixel from screen so it cannot be used again. * * July 1992 Added -f option to output floating point instead of integer pixel * values - slows up the process but useful for correct aspect ratio * correction - GAWW */#include <stdio.h>#include <math.h>#include "malloc_image.h"#define MAX_PIX 100000#define BLACK 0#define WHITE 255#define TRUE 1#define FALSE !TRUEint loop1, loop2;int list_no;float xpix[MAX_PIX], ypix[MAX_PIX];int index;int thresh_sig;double weight;int flag;int no_lists_written;float aspect_ratio;        /* defined as y/x and divide y value by this */int set_aspect, set_threshold, set_file_out, set_file_in;int closed_only;int floating_point;FILE *fp_out;unsigned char **image;int height, width,depth;char file_out[255], file_in[255];int round();int do_delete_t = FALSE;int lowe = FALSE;    /* threshold on average edge magnitude rather than sum */FILE *fp_in;main(argc, argv)int argc;char *argv[];{    char *temp;    int count;    char ch;    set_aspect = FALSE;    set_file_out = FALSE;    set_file_in = FALSE;    set_threshold = FALSE;    closed_only = FALSE;    aspect_ratio = 1.0;    thresh_sig = 1000;    floating_point = FALSE;    if (argc > 1) {        count = 0;        do {            count++;            temp = argv[count];            if (*argv[count] == '-') {                ch = *(++temp);                switch (ch) {                case 'o':                    count++;                    strcpy(file_out, argv[count]);                    set_file_out = TRUE;                    break;                case 'i':                    count++;                    strcpy(file_in, argv[count]);                    set_file_in = TRUE;                    break;                case 'd':                    do_delete_t = TRUE;                    break;                case 'a':                    count++;                    aspect_ratio = atof(argv[count]);                    set_aspect = TRUE;                    break;                case 't':                    count++;                    thresh_sig = atoi(argv[count]);                    set_threshold = TRUE;                    break;                case 'c':                    closed_only = TRUE;                    break;                case 'f':                    floating_point = TRUE;                    break;                case 'l':                    lowe = TRUE;                    break;                default:                    printf("error on command line\n");                }            }            else {                printf("error on command line\n");                exit();            }        } while (count < argc - 1);		/***        if (floating_point == TRUE)            printf("output is floating point\n");        else            printf("output is integer\n");        if (set_threshold == FALSE)            printf("using default threshold %d\n", thresh_sig);        if (set_aspect == FALSE)            printf("using default aspect_ratio %f\n", aspect_ratio);        ***/        link_and_save(1);    }    else {        printf("                PROGRAM LINKNEW\n");        printf("reads in an image with background set to 1 and edge pixels\n");        printf("set to values between 2 and 254\n");        printf("traces around the pixels storing the lists in a file as\n");        printf("lists of pixels\n");        printf("\n\n");        printf("   linknew -i file_in -o file_out -a aspect ratio -t threshold -c\n");        printf("\noptions:\n");        printf("     c    find closed lists only\n");        printf("     a    input aspect ratio (y/x)\n");        printf("     d    delete T junctions\n");        printf("     t    threshold - lists below not saved\n");        printf("     i    input image file name \n");        printf("     o    output list file name\n");        printf("     f    floating point outputs (default is integers)\n");        printf("     l    Lowe type threshold on average edge magnitude\n");        printf("\n");        printf("options a and t have defaults\n");        exit();    }}link_and_save(option)int option;/* * option used to determine if all lists (0) or only the strongest (1) are * saved to disk * */{    flag = FALSE;        /* at start only - no lists */    no_lists_written = 0;    read_pgm_header(file_in,&width,&height);    image = malloc_char_image(width,height);    read_image_body(image,width,height);    if (do_delete_t)        delete_T();    /* clean up image, make all object 8 connected */    clean();    /* remove isolated points - of no interest to us here */    remove_isolated();    if ((fp_out = fopen(file_out, "w")) == NULL) {        printf("file %s cannot be created - aborting\n", file_out);        exit();    }    /* put magic name at top of file */    if (floating_point == TRUE)        fprintf(fp_out, "pixel_float\n");    else        fprintf(fp_out, "pixel\n");    /* link open edges */    list_no = 0;	/***    printf("generating open lists...\n");	***/    link_open(option);    /* remove isolated points - of no interest to us here */    remove_isolated();    /* link closed edges */	/***    printf("generating closed lists...\n");	***/    link_closed(option);    /* remove isolated points - of no interest to us here */    remove_isolated;    fprintf(fp_out, "  -1   -1\n");    close(fp_out);    printf("total number of lists: %d\n", list_no);    if (option == 1)        printf("number written to disk: %d\n", no_lists_written);}/* delete 4-way T junctions - prevents  2 sides of a Y fork joining later */delete_T(){    int loop1, loop2;    int loop3, loop4;    unsigned char i1, i2, i3, i4;    int number;    counting_pixels();    /***    printf("deleting 2X2 spots...\n\n");    for (loop1 = 2; loop1 < height-1; loop1++)        for (loop2 = 2; loop2 < width-1; loop2++)            if ((image[loop1][loop2] != BLACK) &&                (image[loop1-1][loop2] != BLACK) &&                (image[loop1][loop2-1] != BLACK) &&                (image[loop1-1][loop2-1] != BLACK))            {                for (loop3 = -2; loop3 <= 1; loop3++)                    for (loop4 = -2; loop4 <= 1; loop4++)                    image[loop1+loop3][loop2+loop4] = BLACK;            }    ***/    printf("deleting 4-way T junctions...\n\n");    for (loop1 = 1; loop1 < height - 1; loop1++)        for (loop2 = 1; loop2 < width - 1; loop2++) {            if ((image[loop1][loop2] != BLACK) &&                (image[loop1-1][loop2] != BLACK) &&                (image[loop1+1][loop2] != BLACK) &&                (image[loop1][loop2+1] != BLACK))                {                    image[loop1][loop2] = BLACK;                    image[loop1-1][loop2] = BLACK;                    image[loop1+1][loop2] = BLACK;                    image[loop1][loop2+1] = BLACK;                }            else if ((image[loop1][loop2] != BLACK) &&                (image[loop1][loop2-1] != BLACK) &&                (image[loop1][loop2+1] != BLACK) &&                (image[loop1+1][loop2] != BLACK))                {                    image[loop1][loop2] = BLACK;                    image[loop1][loop2-1] = BLACK;                    image[loop1][loop2+1] = BLACK;                    image[loop1+1][loop2] = BLACK;                }            else if ((image[loop1][loop2] != BLACK) &&                (image[loop1-1][loop2] != BLACK) &&                (image[loop1+1][loop2] != BLACK) &&                (image[loop1][loop2-1] != BLACK))                {                    image[loop1][loop2] = BLACK;                    image[loop1-1][loop2] = BLACK;                    image[loop1+1][loop2] = BLACK;                    image[loop1][loop2-1] = BLACK;                }            else if ((image[loop1][loop2] != BLACK) &&                (image[loop1][loop2-1] != BLACK) &&                (image[loop1][loop2+1] != BLACK) &&                (image[loop1-1][loop2] != BLACK))                {                    image[loop1][loop2] = BLACK;                    image[loop1][loop2-1] = BLACK;                    image[loop1][loop2+1] = BLACK;                    image[loop1-1][loop2] = BLACK;                }        }    counting_pixels();}clean(){    int loop1, loop2;    unsigned char i1, i2, i3, i4;    int number;    /* clear border */    for (loop1 = 0; loop1 < height; loop1++) {        image[loop1][0] = BLACK;        image[loop1][width - 1] = BLACK;    }    for (loop1 = 0; loop1 < width; loop1++) {        image[0][loop1] = BLACK;        image[height - 1][loop1] = BLACK;    }    counting_pixels();    for (loop1 = 1; loop1 < height - 1; loop1++)        for (loop2 = 1; loop2 < width - 1; loop2++)            if (image[loop1][loop2] != BLACK) {                i1 = image[loop1 - 1][loop2];                i2 = image[loop1][loop2 - 1];                i3 = image[loop1 + 1][loop2];                i4 = image[loop1][loop2 + 1];                if ((i1 != BLACK) && (i2 != BLACK)) {                    image[loop1][loop2] = BLACK;                }                else if ((i2 != BLACK) && (i3 != BLACK)) {                    image[loop1][loop2] = BLACK;                }                else if ((i3 != BLACK) && (i4 != BLACK)) {                    image[loop1][loop2] = BLACK;                }                else if ((i4 != BLACK) && (i1 != BLACK)) {                    image[loop1][loop2] = BLACK;                }            }    counting_pixels();}counting_pixels(){    int loop1, loop2;    long number;    number = 0;