/* Copyright (c) 1992 Regents of the University of California */

#ifndef lint
static char SCCSid[] = "@(#)pextrem.c 2.1 8/21/92 LBL";
#endif

/*
 * Find extrema points in a Radiance picture.
 */

#include  <stdio.h>
#ifdef MSDOS
#include  <fcntl.h>
#endif
#include  "color.h"


int  orig = 0;

int  wrongformat = 0;

COLOR  expos = WHTCOLOR;

extern char  *malloc();


headline(s)                     /* check header line */
char  *s;
{
	char    fmt[32];
	double  d;
	COLOR   ctmp;

	if (isformat(s)) {                      /* format */
		formatval(fmt, s);
		wrongformat = strcmp(fmt, COLRFMT);
	}
	if (!orig)
		return;
	if (isexpos(s)) {                       /* exposure */
		d = exposval(s);
		scalecolor(expos, d);
	} else if (iscolcor(s)) {               /* color correction */
		colcorval(ctmp, s);
		multcolor(expos, ctmp);
	}
}


main(argc, argv)
int  argc;
char  *argv[];
{
	int  i;
	int  xres, yres;
	int  y;
	register int  x;
	COLR  *scan;
	COLR  cmin, cmax;
	int  xmin, ymin, xmax, ymax;
#ifdef MSDOS
	extern int  _fmode;
	_fmode = O_BINARY;
	setmode(fileno(stdin), O_BINARY);
#endif
	for (i = 1; i < argc; i++)      /* get options */
		if (!strcmp(argv[i], "-o"))
			orig++;
		else
			break;

	if (i == argc-1 && freopen(argv[i], "r", stdin) == NULL) {
		fprintf(stderr, "%s: can't open input \"%s\"\n",
				argv[0], argv[i]);
		exit(1);
	}
					/* get our header */
	if (getheader(stdin, headline, NULL) < 0 || wrongformat ||
			fgetresolu(&xres, &yres, stdin) < 0) {
		fprintf(stderr, "%s: bad picture format\n", argv[0]);
		exit(1);
	}
	if ((scan = (COLR *)malloc(xres*sizeof(COLR))) == NULL) {
		fprintf(stderr, "%s: out of memory\n", argv[0]);
		exit(1);
	}
	setcolr(cmin, 1e10, 1e10, 1e10);
	setcolr(cmax, 0., 0., 0.);
					/* find extrema */
	for (y = yres-1; y >= 0; y--) {
		if (freadcolrs(scan, xres, stdin) < 0) {
			fprintf(stderr, "%s: read error on input\n", argv[0]);
			exit(1);
		}
		for (x = xres; x-- > 0; ) {
			if (scan[x][EXP] > cmax[EXP] ||
					(scan[x][EXP] == cmax[EXP] &&
					 normbright(scan[x]) >
						normbright(cmax))) {
				copycolr(cmax, scan[x]);
				xmax = x; ymax = y;
			}
			if (scan[x][EXP] < cmin[EXP] ||
					(scan[x][EXP] == cmin[EXP] &&
					 normbright(scan[x]) <
						normbright(cmin))) {
				copycolr(cmin, scan[x]);
				xmin = x; ymin = y;
			}
		}
	}
	free((char *)scan);
	printf("%d %d\t%e %e %e\n", xmin, ymin,
			colrval(cmin,RED)/colval(expos,RED),
			colrval(cmin,GRN)/colval(expos,GRN),
			colrval(cmin,BLU)/colval(expos,BLU));
	printf("%d %d\t%e %e %e\n", xmax, ymax,
			colrval(cmax,RED)/colval(expos,RED),
			colrval(cmax,GRN)/colval(expos,GRN),
			colrval(cmax,BLU)/colval(expos,BLU));
	exit(0);
}