--- ray/src/px/oki20c.c	1989/10/20 20:36:02	1.7
+++ ray/src/px/oki20c.c	1991/05/06 13:14:23	1.11
@@ -24,7 +24,15 @@ static char SCCSid[] = "$SunId$ LBL";
 
 #define  sub_add(sub)	(2-(sub))	/* map subtractive to additive pri. */
 
+#ifdef  BSD
+#define  clearlbuf()	bzero((char *)lpat, sizeof(lpat))
+#else
+#define  clearlbuf()	(void)memset((char *)lpat, 0, sizeof(lpat))
+#endif
 
+long  lpat[NCOLS][3];
+
+
 main(argc, argv)
 int  argc;
 char  *argv[];
@@ -56,7 +64,10 @@ char  *fname;
 		return(-1);
 	}
 				/* discard header */
-	getheader(input, NULL);
+	if (checkheader(input, COLRFMT, NULL) < 0) {
+		fprintf(stderr, "%s: not a Radiance picture\n", fname);
+		return(-1);
+	}
 				/* get picture dimensions */
 	if (fgetresolu(&xres, &yres, input) != (YMAJOR|YDECR)) {
 		fprintf(stderr, "%s: bad picture size\n", fname);
@@ -68,13 +79,15 @@ char  *fname;
 	}
 				/* set line spacing (overlap for knitting) */
 	fputs("\0333\042", stdout);
+				/* clear line buffer */
+	clearlbuf();
 				/* put out scanlines */
 	for (i = yres-1; i >= 0; i--) {
 		if (freadcolrs(scanline, xres, input) < 0) {
 			fprintf(stderr, "%s: read error (y=%d)\n", fname, i);
 			return(-1);
 		}
-		normcolrs(scanline, xres);
+		normcolrs(scanline, xres, 0);
 		plotscan(scanline, xres, i);
 	}
 				/* advance page */
@@ -91,7 +104,6 @@ COLR  scan[];
 int  len;
 int  y;
 {
-	static long  pat[NCOLS][3];
 	int  bpos;
 	register long  c;
 	register int  i, j;
@@ -100,7 +112,7 @@ int  y;
 
 		for (j = 0; j < 3; j++)
 			for (i = 0; i < len; i++)
-				pat[i][j] |= (long)colbit(scan[i],i,j) << bpos;
+				lpat[i][j] |= (long)colbit(scan[i],i,j) << bpos;
 
 	} else {
 
@@ -111,9 +123,9 @@ int  y;
 			putchar(len & 255);
 			putchar(len >> 8);
 			for (i = 0; i < len; i++) {
-				c = pat[i][j] | colbit(scan[i],i,j);
+				c = lpat[i][j] | colbit(scan[i],i,j);
 							/* repeat this row */
-				pat[i][j] = (c & 1) << 23;
+				lpat[i][j] = (c & 1) << 23;
 				putchar(c>>16);
 				putchar(c>>8 & 255);
 				putchar(c & 255);
@@ -131,15 +143,17 @@ register int  x;
 int  s;
 {
 	static int  cerr[NCOLS][3];
-	static int  err[3];
+	static int  err[3], errp[3];
 	int  b;
 	register int  a, ison;
 
 	a = sub_add(s);			/* use additive primary */
 	b = col[a];
+	errp[a] = err[a];
 	err[a] += b + cerr[x][a];
 	ison = err[a] < 128;
 	if (!ison) err[a] -= 256;
-	cerr[x][a] = err[a] /= 2;
+	err[a] /= 3;
+	cerr[x][a] = err[a] + errp[a];
 	return(ison);
 }