22 |
|
/* histogram resolution */ |
23 |
|
#define NRED 24 |
24 |
|
#define NGRN 32 |
25 |
< |
#define NBLU 18 |
25 |
> |
#define NBLU 16 |
26 |
|
#define HMAX NGRN |
27 |
|
/* minimum box count for adaptive partition */ |
28 |
|
#define MINSAMP 7 |
29 |
+ |
/* maximum distance^2 before color reassign */ |
30 |
+ |
#define MAXDST2 5 |
31 |
|
/* maximum frame buffer depth */ |
32 |
|
#define FBDEPTH 8 |
33 |
|
/* color map resolution */ |
34 |
< |
#define MAPSIZ 128 |
34 |
> |
#define MAPSIZ 256 |
35 |
|
/* map a color */ |
36 |
< |
#define map_col(c,p) clrmap[p][ colval(c,p)<1. ? \ |
36 |
> |
#define map_col(c,p) clrmap[ colval(c,p)<1. ? \ |
37 |
|
(int)(colval(c,p)*MAPSIZ) : MAPSIZ-1 ] |
38 |
|
/* color partition tree */ |
39 |
|
#define CNODE short |
44 |
|
#define prim(cn) ((cn)&3) |
45 |
|
#define pval(cn) ((cn)>>2) |
46 |
|
/* our color table */ |
47 |
< |
COLR clrtab[1<<FBDEPTH]; |
47 |
> |
struct tabent { |
48 |
> |
long sum[3]; /* sum of colors using this entry */ |
49 |
> |
long n; /* number of colors */ |
50 |
> |
short ent[3]; /* current table value */ |
51 |
> |
} clrtab[1<<FBDEPTH]; |
52 |
|
/* our color correction map */ |
53 |
< |
static BYTE clrmap[3][MAPSIZ]; |
53 |
> |
static BYTE clrmap[MAPSIZ]; |
54 |
|
/* histogram of colors used */ |
55 |
|
static unsigned histo[NRED][NGRN][NBLU]; |
56 |
|
/* initial color cube boundaries */ |
57 |
|
static int CLRCUBE[3][2] = {0,NRED,0,NGRN,0,NBLU}; |
58 |
|
/* color cube partition */ |
59 |
|
static CNODE ctree[1<<(FBDEPTH+1)]; |
60 |
+ |
/* callback for pixel assignment */ |
61 |
+ |
static int (*set_pixel)(); |
62 |
|
|
63 |
|
|
64 |
< |
COLR * |
65 |
< |
get_ctab(ncolors) /* assign a color table with max ncolors */ |
64 |
> |
int |
65 |
> |
new_ctab(ncolors, cset) /* start new color table with max ncolors */ |
66 |
|
int ncolors; |
67 |
+ |
int (*cset)(); |
68 |
|
{ |
69 |
< |
if (ncolors < 1 || ncolors > 1<<FBDEPTH) |
70 |
< |
return(NULL); |
71 |
< |
/* partition color table */ |
69 |
> |
if (ncolors < 1 || ncolors > 1<<FBDEPTH || cset == NULL) |
70 |
> |
return(0); |
71 |
> |
/* assign pixel callback routine */ |
72 |
> |
set_pixel = cset; |
73 |
> |
/* clear color table */ |
74 |
> |
bzero(clrtab, sizeof(clrtab)); |
75 |
> |
/* partition color space */ |
76 |
|
cut(ctree, FBDEPTH, CLRCUBE, 0, ncolors); |
77 |
|
/* clear histogram */ |
78 |
|
bzero(histo, sizeof(histo)); |
79 |
< |
/* return color table */ |
80 |
< |
return(clrtab); |
79 |
> |
/* return number of colors used */ |
80 |
> |
return(ncolors); |
81 |
|
} |
82 |
|
|
83 |
|
|
85 |
|
get_pixel(col) /* get pixel for color */ |
86 |
|
COLOR col; |
87 |
|
{ |
88 |
+ |
int r, g, b; |
89 |
|
int cv[3]; |
90 |
< |
register CNODE *tp; |
90 |
> |
register union { CNODE *t; struct tabent *e; } p; |
91 |
|
register int h; |
92 |
< |
/* map color */ |
93 |
< |
cv[RED] = map_col(col,RED); |
94 |
< |
cv[GRN] = map_col(col,GRN); |
95 |
< |
cv[BLU] = map_col(col,BLU); |
96 |
< |
/* add to histogram */ |
92 |
> |
/* map color */ |
93 |
> |
r = map_col(col,RED); |
94 |
> |
g = map_col(col,GRN); |
95 |
> |
b = map_col(col,BLU); |
96 |
> |
/* reduce resolution */ |
97 |
> |
cv[RED] = (r*NRED)>>8; |
98 |
> |
cv[GRN] = (g*NGRN)>>8; |
99 |
> |
cv[BLU] = (b*NBLU)>>8; |
100 |
> |
/* add to histogram */ |
101 |
|
histo[cv[RED]][cv[GRN]][cv[BLU]]++; |
102 |
< |
/* find pixel value in tree */ |
103 |
< |
tp = ctree; |
102 |
> |
/* find pixel in tree */ |
103 |
> |
p.t = ctree; |
104 |
|
for (h = FBDEPTH; h > 0; h--) { |
105 |
< |
if (is_pval(*tp)) |
105 |
> |
if (is_pval(*p.t)) |
106 |
|
break; |
107 |
< |
if (cv[prim(*tp)] < part(*tp)) |
108 |
< |
tp++; /* left branch */ |
107 |
> |
if (cv[prim(*p.t)] < part(*p.t)) |
108 |
> |
p.t++; /* left branch */ |
109 |
|
else |
110 |
< |
tp += 1<<h; /* right branch */ |
110 |
> |
p.t += 1<<h; /* right branch */ |
111 |
|
} |
112 |
+ |
h = pval(*p.t); |
113 |
+ |
/* add to color table */ |
114 |
+ |
p.e = clrtab + h; |
115 |
+ |
/* add to sum */ |
116 |
+ |
p.e->sum[RED] += r; |
117 |
+ |
p.e->sum[GRN] += g; |
118 |
+ |
p.e->sum[BLU] += b; |
119 |
+ |
p.e->n++; |
120 |
+ |
/* recompute average */ |
121 |
+ |
r = p.e->sum[RED] / p.e->n; |
122 |
+ |
g = p.e->sum[GRN] / p.e->n; |
123 |
+ |
b = p.e->sum[BLU] / p.e->n; |
124 |
+ |
/* check for movement */ |
125 |
+ |
if (p.e->n == 1 || |
126 |
+ |
(r-p.e->ent[RED])*(r-p.e->ent[RED]) + |
127 |
+ |
(g-p.e->ent[GRN])*(g-p.e->ent[GRN]) + |
128 |
+ |
(b-p.e->ent[BLU])*(b-p.e->ent[BLU]) > MAXDST2) { |
129 |
+ |
p.e->ent[RED] = r; |
130 |
+ |
p.e->ent[GRN] = g; /* reassign pixel */ |
131 |
+ |
p.e->ent[BLU] = b; |
132 |
|
#ifdef notdef |
133 |
< |
printf("distance (%d,%d,%d)\n", |
134 |
< |
cv[RED] - clrtab[pval(*tp)][RED]*NRED/256, |
97 |
< |
cv[GRN] - clrtab[pval(*tp)][GRN]*NGRN/256, |
98 |
< |
cv[BLU] - clrtab[pval(*tp)][BLU]*NBLU/256); |
133 |
> |
printf("pixel %d = (%d,%d,%d) (%d refs)\n", |
134 |
> |
h, r, g, b, p.e->n); |
135 |
|
#endif |
136 |
< |
return(pval(*tp)); |
136 |
> |
(*set_pixel)(h, r, g, b); |
137 |
> |
} |
138 |
> |
return(h); /* return pixel value */ |
139 |
|
} |
140 |
|
|
141 |
|
|
143 |
|
double gam; |
144 |
|
{ |
145 |
|
extern double pow(); |
108 |
– |
double d; |
146 |
|
register int i; |
147 |
|
|
148 |
< |
for (i = 0; i < MAPSIZ; i++) { |
149 |
< |
d = pow(i/(double)MAPSIZ, 1.0/gam); |
113 |
< |
clrmap[RED][i] = d * NRED; |
114 |
< |
clrmap[GRN][i] = d * NGRN; |
115 |
< |
clrmap[BLU][i] = d * NBLU; |
116 |
< |
} |
148 |
> |
for (i = 0; i < MAPSIZ; i++) |
149 |
> |
clrmap[i] = 256.0 * pow(i/(double)MAPSIZ, 1.0/gam); |
150 |
|
} |
151 |
|
|
152 |
|
|
159 |
|
{ |
160 |
|
int kb[3][2]; |
161 |
|
|
162 |
< |
if (c1-c0 == 1) { /* assign color */ |
130 |
< |
clrtab[c0][RED] = ((box[RED][0]+box[RED][1])<<7)/NRED; |
131 |
< |
clrtab[c0][GRN] = ((box[GRN][0]+box[GRN][1])<<7)/NGRN; |
132 |
< |
clrtab[c0][BLU] = ((box[BLU][0]+box[BLU][1])<<7)/NBLU; |
133 |
< |
clrtab[c0][EXP] = COLXS; |
162 |
> |
if (c1-c0 <= 1) { /* assign pixel */ |
163 |
|
*tree = set_pval(c0); |
135 |
– |
#ifdef notdef |
136 |
– |
printf("final box size = (%d,%d,%d)\n", |
137 |
– |
box[RED][1] - box[RED][0], |
138 |
– |
box[GRN][1] - box[GRN][0], |
139 |
– |
box[BLU][1] - box[BLU][0]); |
140 |
– |
#endif |
164 |
|
return; |
165 |
|
} |
166 |
|
/* split box */ |
167 |
|
*tree = split(box); |
168 |
|
bcopy(box, kb, sizeof(kb)); |
169 |
+ |
/* do left (lesser) branch */ |
170 |
|
kb[prim(*tree)][1] = part(*tree); |
171 |
< |
cut(tree+1, height-1, kb, c0, (c0+c1)>>1); /* lesser */ |
171 |
> |
cut(tree+1, height-1, kb, c0, (c0+c1)>>1); |
172 |
> |
/* do right branch */ |
173 |
|
kb[prim(*tree)][0] = part(*tree); |
174 |
|
kb[prim(*tree)][1] = box[prim(*tree)][1]; |
175 |
< |
cut(tree+(1<<height), height-1, kb, (c0+c1)>>1, c1); /* greater */ |
175 |
> |
cut(tree+(1<<height), height-1, kb, (c0+c1)>>1, c1); |
176 |
|
} |
177 |
|
|
178 |
|
|