Page 310 -

Section 9.4 Segmentation, Clustering, and Graphs 278

FIGURE 9.21: Segmentations of images obtained using the mean shift algorithm. This
figure was originally published as Figure 10 of “Mean Shift: A Robust Approach Toward
Feature Space Analysis,” by D. Comaniciu and P. Meer, IEEE Transactions on Pattern
Analysis and Machine Intelligence, 2002 c IEEE, 2002.

• A directed graph is one in which edges (a, b)and (b, a) are distinct; such a
graph is drawn with arrowheads indicating which direction is intended.
• An undirected graph is one in which no distinction is drawn between edges
(a, b)and (b, a).
• A weighted graph is one in which a weight is associated with each edge.

• Two edges are consecutive if they have a vertex in common.
• A path is a sequence of consecutive edges.
• A circuit is a path which ends at the vertex at which it begins.

• A self-loop is an edge that has the same vertex at each end; self-loops don’t
occur in our applications.

• Two vertices are said to be connected when there is a sequence of edges starting
at the one and ending at the other; if the graph is directed, then the arrows
in this sequence must point the right way.
• A connected graph is one where every pair of vertices is connected.

• A tree is a connected graph with no circuits.