22 |
|
colormap color; /* quantization colormap */ |
23 |
|
int n; /* number of colors in it */ |
24 |
|
|
25 |
+ |
#define ERRMAX 20 /* maximum allowed propagated error, |
26 |
+ |
if >=255 then no clamping */ |
27 |
+ |
|
28 |
|
/*----------------------------------------------------------------------*/ |
29 |
|
|
30 |
|
ciq(dith,nw,synth,cm) |
51 |
|
} |
52 |
|
picwritecm(color); |
53 |
|
|
54 |
+ |
initializeclosest(); |
55 |
|
if (dith) |
56 |
|
draw_dith(ocm); |
57 |
|
else { |
143 |
|
Q[0] = Q[1] = Q[2] = 0; |
144 |
|
picreadline3(y,iline); |
145 |
|
for (p=P, q=Q, x=0; x<xmax; x++, p+=3, q+=3) { |
146 |
< |
rr = ocm[0][iline[x].r]+p[0]; |
147 |
< |
gg = ocm[1][iline[x].g]+p[1]; /* ideal */ |
148 |
< |
bb = ocm[2][iline[x].b]+p[2]; |
146 |
> |
rr = p[0]; |
147 |
> |
if (rr<-ERRMAX) rr = -ERRMAX; else if (rr>ERRMAX) rr = ERRMAX; |
148 |
> |
gg = p[1]; |
149 |
> |
if (gg<-ERRMAX) gg = -ERRMAX; else if (gg>ERRMAX) gg = ERRMAX; |
150 |
> |
bb = p[2]; |
151 |
> |
if (bb<-ERRMAX) bb = -ERRMAX; else if (bb>ERRMAX) bb = ERRMAX; |
152 |
> |
/* now rr,gg,bb is propagated color */ |
153 |
> |
rr += ocm[0][iline[x].r]; |
154 |
> |
gg += ocm[1][iline[x].g]; /* ideal */ |
155 |
> |
bb += ocm[2][iline[x].b]; |
156 |
|
if (rr<0) rr = 0; else if (rr>255) rr = 255; |
157 |
|
if (gg<0) gg = 0; else if (gg>255) gg = 255; |
158 |
|
if (bb<0) bb = 0; else if (bb>255) bb = 255; |