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Left: A given set W = {S1, S2, .., S6} of linear segments around a candidate point p0. Right: A graph G w for the set of linear segments. We assume an angle tolerance α such that all angle constraints are satisfied. Several node pairs of the graph are not connected by an edge due to the convexity constraint, which is not satisfied for an assumed convexity tolerance t. The red nodes of the graph are the nodes of the optimal maximal clique G c opt. The corresponding valid configuration Copt is marked in red on the left figure. 

Left: A given set W = {S1, S2, .., S6} of linear segments around a candidate point p0. Right: A graph G w for the set of linear segments. We assume an angle tolerance α such that all angle constraints are satisfied. Several node pairs of the graph are not connected by an edge due to the convexity constraint, which is not satisfied for an assumed convexity tolerance t. The red nodes of the graph are the nodes of the optimal maximal clique G c opt. The corresponding valid configuration Copt is marked in red on the left figure. 

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We develop an approach for detection of ruins of livestock enclosures in alpine areas captured by high-resolution remotely sensed images. These structures are usually of approximately rectangular shape and appear in images as faint fragmented contours in complex background. We address this problem by introducing a new rectangularity feature that qu...

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Context 1
... smaller than the set of graph cliques K(G w ), the number of times the rectangularity measure ρ needs to be evaluated in Eq. (10) is considerably reduced in compari- son to Eq. (8). Since, in addition, there are efficient algo- rithms for the search of maximal cliques [2], computing the rectangularity feature is not computationally demanding. Fig. 4 (left) shows an example of a given set W = {S 1 , S 2 , .., S 6 } of linear segments and the optimal config- uration C opt = {S 1 , S 2 , S 3 , S 5 } in red, while Fig. 4 (right) shows the corresponding graph G w and the optimal max- imal clique G c opt in red. There are two additional max- imal cliques G c 1 and G c 2 and corresponding valid ...
Context 2
... to Eq. (8). Since, in addition, there are efficient algo- rithms for the search of maximal cliques [2], computing the rectangularity feature is not computationally demanding. Fig. 4 (left) shows an example of a given set W = {S 1 , S 2 , .., S 6 } of linear segments and the optimal config- uration C opt = {S 1 , S 2 , S 3 , S 5 } in red, while Fig. 4 (right) shows the corresponding graph G w and the optimal max- imal clique G c opt in red. There are two additional max- imal cliques G c 1 and G c 2 and corresponding valid config- urations C 1 = {S 2 , S 3 , S 4 , S 6 }, C 2 = {S 1 , S 2 , S 3 , S 4 }. They, however, have lower rectangularity values ρ(G c 1 ...

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