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Two elements will tend to group together if they lie on the same contour
Texture Segmentation
Regions of similar texture properties are grouped together
Similarity
Similar looking items get grouped together
Proximity
Items that are close to each other get grouped together
Parallelism
Parallel contours are likely to belong together
Symmetry
Symmetrical regions are likely to be seen as a group
Common Region
Items that appear to be part of the same larger area will be grouped together
Connectedness
Items that are connected will be grouped