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-rw-r--r--SD-VBS/benchmarks/multi_ncut/src/c/segment-graph.c95
1 files changed, 95 insertions, 0 deletions
diff --git a/SD-VBS/benchmarks/multi_ncut/src/c/segment-graph.c b/SD-VBS/benchmarks/multi_ncut/src/c/segment-graph.c
new file mode 100644
index 0000000..13b219b
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+++ b/SD-VBS/benchmarks/multi_ncut/src/c/segment-graph.c
@@ -0,0 +1,95 @@
1/********************************
2Author: Sravanthi Kota Venkata
3********************************/
4
5#include <stdio.h>
6#include <stdlib.h>
7#include "segment.h"
8
9// threshold function
10#define THRESHOLD(size, c) (c/size)
11
12int find(universe* u, int x)
13{
14 int y=x;
15 while (y != u->elts[y].p)
16 y = u->elts[y].p;
17 u->elts[x].p = y;
18 return y;
19}
20
21void join(universe* u, int x, int y)
22{
23 if (u->elts[x].rank > u->elts[y].rank)
24 {
25 u->elts[y].p = x;
26 u->elts[x].size += u->elts[y].size;
27 }
28 else
29 {
30 u->elts[x].p = y;
31 u->elts[y].size += u->elts[x].size;
32 if (u->elts[x].rank == u->elts[y].rank)
33 u->elts[y].rank++;
34 }
35 u->num--;
36 return ;
37}
38
39universe *segment_graph(int num_vertices, int num_edges, edge *edges, float c, F2D* edgeWeights, F2D* in, I2D* ind,
40 universe* u)
41{
42 float threshold[num_vertices];
43 int i, a, b, j, k;
44 //universe *u;
45 //F2D *edgeWeights;
46 I2D *indices;
47
48 edgeWeights = fResetHandle(edgeWeights,1,num_edges);
49
50 for(i=0; i<num_edges; i++)
51 asubsref(edgeWeights,i) = edges[i].w;
52
53 // sort edges by weight
54 indices = fResortIndices(edgeWeights,1, in, ind);
55
56 // make a disjoint-set forest
57 //u = (universe*)malloc(sizeof(universe));
58 //u->elts = (uni_elt*)malloc(sizeof(uni_elt)*num_vertices);
59 u->num = num_vertices;
60 for(i=0; i<num_vertices; i++)
61 {
62 u->elts[i].rank = 0;
63 u->elts[i].size = 1;
64 u->elts[i].p = i;
65 }
66
67 // init thresholds
68 for (i = 0; i < num_vertices; i++)
69 arrayref(threshold,i) = THRESHOLD(1,c);
70
71 // for each edge, in non-decreasing weight order...
72 for (i = 0; i < num_edges; i++)
73 {
74 edge *pedge = &edges[ asubsref(indices,i) ];
75
76 // components conected by this edge
77 a = find(u, pedge->a);
78 b = find(u, pedge->b);
79 if (a != b)
80 {
81 if ((pedge->w <= arrayref(threshold,a)) && (pedge->w <= arrayref(threshold,b)))
82 {
83 join(u, a, b);
84 a = find(u, a);
85 arrayref(threshold,a) = pedge->w + THRESHOLD(u->elts[a].size, c);
86 }
87 }
88 }
89
90 //fFreeHandle(edgeWeights);
91 //iFreeHandle(indices);
92
93 return u;
94}
95