rlebox.c

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/* 
 * rlebox.c - Find bounding box for an RLE image
 * 
 * Author:  Spencer W. Thomas
 *      Computer Science Dept.
 *      University of Utah
 * Date:    Wed Feb 11 1987
 * Copyright (c) 1987, University of Utah
 */
static char rcsid[] = "$Header: /l/spencer/src/urt/tools/RCS/rlebox.c,v 3.0.1.3 1992/04/30 14:11:24 spencer Exp $";
/*
rlebox()            Tag the file.
*/

#include <stdio.h>
#include "rle.h"
#include "rle_raw.h"

/*****************************************************************
 * TAG( main )
 * 
 * Find a bounding box for an RLE image.
 *
 * Usage:
 *  rlebox [-v] [-c] [infile]
 * Inputs:
 *  -v:     Verbose mode - identifies numbers with text.
 *          Otherwise, just prints numbers.
 *  -c:     Outputs corners of box in an order useful for use
 *          as arguments to the crop program:
 *          crop `rlebox -c foo.rle` foo.rle
 *  infile:     The input file.
 * Outputs:
 *  Prints the bounding box for the rle file.  That is, it finds the
 *  minimum and maximum values of x and y for which there is some
 *  non-background data.
 * Assumptions:
 *  
 * Algorithm:
 *  Read the image file and find the smallest and largest X and Y
 *  coordinates of real image data.  Use raw interface for speed.
 */
void
main( argc, argv )
int argc;
char **argv;
{
    extern void rle_box();
    rle_hdr the_hdr;
    char * rlefname = NULL;
    int vflag = 0, cflag = 0, margin = 0;
    int xmin, xmax, ymin, ymax;
    int rle_cnt, rle_err;

    if ( scanargs( argc, argv, "% v%- c%- m%-margin!d infile%s",
           &vflag, &cflag, &margin, &margin,
           &rlefname ) == 0 )
    exit( 1 );

    the_hdr = *rle_hdr_init( (rle_hdr *)NULL );
    rle_names( &the_hdr, cmd_name( argv ), rlefname, 0 );
    the_hdr.rle_file = rle_open_f(the_hdr.cmd, rlefname, "r");

    for ( rle_cnt = 0;
      (rle_err = rle_get_setup( &the_hdr )) == RLE_SUCCESS;
      rle_cnt++ )
    {

    rle_box( &the_hdr, &xmin, &xmax, &ymin, &ymax );

    /* If margin, enlarge bounds.  Don't let them go negative */
    if ( margin )
    {
        xmax += margin;
        ymax += margin;
        xmin -= margin;
        if ( xmin < 0 )
        xmin = 0;
        ymin -= margin;
        if ( ymin < 0 )
        ymin = 0;
    }

    if ( cflag )
        printf( vflag ? "xmin=%d ymin=%d xmax=%d ymax=%d\n" :
            "%d %d %d %d\n",
            xmin, ymin, xmax, ymax );
    else
        printf( vflag ? "xmin=%d xmax=%d ymin=%d ymax=%d\n" :
            "%d %d %d %d\n",
            xmin, xmax, ymin, ymax );
    }

    /* Check for an error.  EOF or EMPTY is ok if at least one image
     * has been read.  Otherwise, print an error message.
     */
    if ( rle_cnt == 0 || (rle_err != RLE_EOF && rle_err != RLE_EMPTY) )
    rle_get_error( rle_err, the_hdr.cmd, rlefname );

    exit( 0 );
}