1. A method of providing image data, the method comprising: identifying information associated with an object in an image; constructing a graph based on the identified information associated with the object in the image, wherein the graph includes connectivity similarity for a plurality of nodes in the graph, and wherein constructing a graph includes defining effective distances for valid paths between two graph nodes and choosing the minimum value of the effective distances as an inter-nodal distance between the two graph nodes; performing local smoothing between spatially close graph nodes; and providing image data representing the object based on results of the local smoothing.