--- ray/src/px/ciq.c	1989/04/07 13:30:09	1.3
+++ ray/src/px/ciq.c	2004/03/28 20:33:13	2.5
@@ -1,9 +1,6 @@
-/* Copyright 1988 Regents of the University of California */
-
 #ifndef lint
-static char SCCSid[] = "$SunId$ LBL";
+static const char	RCSid[] = "$Id: ciq.c,v 2.5 2004/03/28 20:33:13 schorsch Exp $";
 #endif
-
 /*
 CIQ - main program for color image quantization
 options for Floyd-Steinberg dithering by minimization of accumulated error
@@ -13,6 +10,9 @@ Paul Heckbert	16 April 82, cleaned up 8 June 86
 Greg Ward	1 March 88, modified for arbitrary picture sizes
 */
 
+#include <string.h>
+
+#include "standard.h"
 #include "ciq.h"
 
 #define table(m,r,g,b) hist[m[0][r]|m[1][g]|m[2][b]]  /* histogram/pvtable */
@@ -22,14 +22,24 @@ int hist[len];		/* list of frequencies or pixelvalues 
 colormap color;		/* quantization colormap */
 int n;			/* number of colors in it */
 
+#define ERRMAX 20	/* maximum allowed propagated error,
+			   if >=255 then no clamping */
+
+static void sample(colormap ocm);
+static void convertmap(colormap in, colormap out);
+static void draw_nodith(colormap ocm);
+static void draw_dith(colormap ocm);
+
+
 /*----------------------------------------------------------------------*/
 
-ciq(dith,nw,synth,cm)
-int dith;		/* is dithering desired? 0=no, 1=yes */
-int nw;			/* number of colors wanted in output image */
-int synth;		/* synthesize colormap? 0=no, 1=yes */
-colormap cm;		/* quantization colormap */
-			/* read if synth=0; always written */
+void
+ciq(
+	int dith,		/* is dithering desired? 0=no, 1=yes */
+	int nw,			/* number of colors wanted in output image */
+	int synth,		/* synthesize colormap? 0=no, 1=yes */
+	colormap cm		/* quantization colormap */
+)			/* read if synth=0; always written */
 {
     int na,i;
     colormap ocm;
@@ -40,7 +50,7 @@ colormap cm;		/* quantization colormap */
     if (synth)
 	n = makecm(nw,&na);	/* analyze histogram and synthesize colormap */
     else {
-	bcopy(cm,color,sizeof color);
+	memcpy((void *)color,(void *)cm,sizeof color);
 	n = nw;
 	na = 0;
 	for (i=0; i<len; i++) if (hist[i]) na++;
@@ -48,6 +58,7 @@ colormap cm;		/* quantization colormap */
     }
     picwritecm(color);
 
+    initializeclosest();
     if (dith)
 	draw_dith(ocm);
     else {
@@ -56,14 +67,16 @@ colormap cm;		/* quantization colormap */
 	draw_nodith(ocm);
     }
 
-    bcopy(color,cm,sizeof color);
+    memcpy((void *)cm,(void *)color,sizeof color);
     /*endclosest();*/
 }
 
 /*----------------------------------------------------------------------*/
 
-sample(ocm)		/* make color frequency table (histogram) */
-colormap ocm;
+static void
+sample(		/* make color frequency table (histogram) */
+	colormap ocm
+)
 {
     register int x,y;
     register rgbpixel *lp;
@@ -81,11 +94,14 @@ colormap ocm;
 	for (lp=line, x=0; x<xmax; x++, lp++)
 	    table(map,lp->r,lp->g,lp->b)++;
     }
-    free((char *)line);
+    free((void *)line);
 }
 
-convertmap(in,out)		/* convert to shifted color map */
-register colormap in,out;
+static void
+convertmap(		/* convert to shifted color map */
+	register colormap in,
+	register colormap out
+)
 {
     register int j;
 
@@ -96,8 +112,10 @@ register colormap in,out;
     }
 }
 
-draw_nodith(ocm)	/* quantize without dithering */
-colormap ocm;			/* colormap for orig */
+static void
+draw_nodith(	/* quantize without dithering */
+	colormap ocm			/* colormap for orig */
+)
 {
     register int x,y;
     register rgbpixel *lp;
@@ -115,12 +133,14 @@ colormap ocm;			/* colormap for orig */
 	    oline[x] = table(map,lp->r,lp->g,lp->b);
 	picwriteline(y,oline);
     }
-    free((char *)iline);
-    free((char *)oline);
+    free((void *)iline);
+    free((void *)oline);
 }
 
-draw_dith(ocm)			/* quantize with dithering */
-colormap ocm;			/* colormap for orig */
+static void
+draw_dith(			/* quantize with dithering */
+	colormap ocm			/* colormap for orig */
+)
 {
     register int *p,*q,rr,gg,bb,v,x,y,*P,*Q,*R;
     int *buf;
@@ -139,9 +159,16 @@ colormap ocm;			/* colormap for orig */
 	Q[0] = Q[1] = Q[2] = 0;
 	picreadline3(y,iline);
 	for (p=P, q=Q, x=0; x<xmax; x++, p+=3, q+=3) {
-	    rr = ocm[0][iline[x].r]+p[0];
-	    gg = ocm[1][iline[x].g]+p[1];	/* ideal */
-	    bb = ocm[2][iline[x].b]+p[2];
+	    rr = p[0];
+	    if (rr<-ERRMAX) rr = -ERRMAX; else if (rr>ERRMAX) rr = ERRMAX;
+	    gg = p[1];
+	    if (gg<-ERRMAX) gg = -ERRMAX; else if (gg>ERRMAX) gg = ERRMAX;
+	    bb = p[2];
+	    if (bb<-ERRMAX) bb = -ERRMAX; else if (bb>ERRMAX) bb = ERRMAX;
+	    /* now rr,gg,bb is propagated color */
+	    rr += ocm[0][iline[x].r];
+	    gg += ocm[1][iline[x].g];	/* ideal */
+	    bb += ocm[2][iline[x].b];
 	    if (rr<0) rr = 0; else if (rr>255) rr = 255;
 	    if (gg<0) gg = 0; else if (gg>255) gg = 255;
 	    if (bb<0) bb = 0; else if (bb>255) bb = 255;
@@ -158,7 +185,7 @@ colormap ocm;			/* colormap for orig */
 	}
 	picwriteline(y,oline);
     }
-    free((char *)iline);
-    free((char *)oline);
-    free((char *)buf);
+    free((void *)iline);
+    free((void *)oline);
+    free((void *)buf);
 }