1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
|
#include <gdk-pixbuf/gdk-pixbuf.h>
#include <glib.h>
#include <string.h>
#ifndef INTERVAL
#define INTERVAL 8
#endif
#define BLOCKS (256 / INTERVAL)
struct cell {
int count;
struct cell *max;
};
struct hst {
struct cell cells[BLOCKS][BLOCKS][BLOCKS];
GList *list;
};
static inline void
pixbuf_get(GdkPixbuf *pixbuf, guchar **pixels,
gint *width, gint *height, gint *nch, gint *stride)
{
if (pixels) *pixels = gdk_pixbuf_get_pixels(pixbuf);
if (width) *width = gdk_pixbuf_get_width(pixbuf);
if (height) *height = gdk_pixbuf_get_height(pixbuf);
if (nch) *nch = gdk_pixbuf_get_n_channels(pixbuf);
if (stride) *stride = gdk_pixbuf_get_rowstride(pixbuf);
}
static gint
compare_cell(gconstpointer a, gconstpointer b)
{
const struct cell *cell1 = a;
const struct cell *cell2 = b;
return cell1->count - cell2->count;
}
static void
calculate_index(struct hst *hst, struct cell *cell, int *i, int *j, int *k)
{
size_t offset = cell - &hst->cells[0][0][0];
*i = offset / (BLOCKS*BLOCKS);
*j = (offset - *i * (BLOCKS*BLOCKS)) / BLOCKS;
*k = (offset - *i * (BLOCKS*BLOCKS) - *j * BLOCKS);
}
static void
add_neighbors(struct hst *hst, struct cell *cell)
{
int i, j, k, ci, cj, ck;
calculate_index(hst, cell, &ci, &cj, &ck);
for (i = MAX(ci - 1, 0); i < MIN(ci + 1, BLOCKS); ++i) {
for (j = MAX(cj - 1, 0); j < MIN(cj + 1, BLOCKS); ++j) {
for (k = MAX(ck - 1, 0); k < MIN(ck + 1, BLOCKS); ++k) {
if (hst->cells[i][j][k].count <= cell->count &&
hst->cells[i][j][k].max == NULL) {
hst->cells[i][j][k].max = cell->max;
add_neighbors(hst, &hst->cells[i][j][k]);
}
}
}
}
hst->list = g_list_remove(hst->list, cell);
}
int
main(int argc, char *argv[])
{
GdkPixbuf *image;
gint x, y, width, height, nch, stride;
int i, j, k;
guchar *p, *row;
int cluster = 0;
struct hst hst;
struct cell *cell;
g_type_init();
memset(&hst, 0, sizeof hst);
if (argc < 2)
return 1;
image = gdk_pixbuf_new_from_file(argv[1], NULL);
if (!image)
return 1;
pixbuf_get(image, &row, &width, &height, &nch, &stride);
for (y = 0; y < height; ++y, row += stride)
for (x = 0, p = row; x < width; ++x, p += nch)
++hst.cells[p[0] / INTERVAL][p[1] / INTERVAL][p[2] / INTERVAL].count;
for (i = 0; i < BLOCKS; ++i)
for (j = 0; j < BLOCKS; ++j)
for (k = 0; k < BLOCKS; ++k)
hst.list = g_list_insert_sorted(hst.list,
&hst.cells[i][j][k],
compare_cell);
while (hst.list) {
cell = g_list_nth_data(hst.list, 0);
cell->max = cell;
add_neighbors(&hst, cell);
++cluster;
}
printf("cluster: %d\n", cluster);
pixbuf_get(image, &row, &width, &height, &nch, &stride);
for (y = 0; y < height; ++y, row += stride) {
for (x = 0, p = row; x < width; ++x, p += nch) {
cell = &hst.cells[p[0] / INTERVAL][p[1] / INTERVAL][p[2] / INTERVAL];
calculate_index(&hst, cell->max, &i, &j, &k);
p[0] = i * INTERVAL + INTERVAL / 2;
p[1] = j * INTERVAL + INTERVAL / 2;
p[2] = k * INTERVAL + INTERVAL / 2;
}
}
gdk_pixbuf_save(image, argc > 2 ? argv[2] : "hst.tiff", "tiff", NULL, NULL);
return 0;
}
|
