randcomponenten

Randcomponenten is a term used in Dutch to describe connected components that lie on the boundary of a domain. In computational geometry and image analysis, a binary image consists of foreground and background pixels, and the connected components of the foreground form distinct regions. Randcomponenten are those components that intersect the image border or the boundary of the region of interest. They are contrasted with interior components, which do not touch the boundary.

In topology, randcomponenten can also refer to the components of the boundary of a topological space: the boundary of a set is the collection of points where every neighborhood intersects both the set and its complement, and a boundary component is a maximal connected subset of that boundary.

Detection and analysis of randcomponenten typically use a connected-components labeling approach, such as flood fill, breadth-first search, depth-first search, or union-find. After labeling, each component is examined to determine whether it contacts the boundary. In image processing, identifying randcomponenten is useful to distinguish objects that touch the image edge from fully enclosed objects, and to remove or treat border artifacts during preprocessing.

Applications include object extraction in binary images, morphological analysis, preprocessing in computer vision, and geographic information systems. Limitations arise in noisy data, where spurious border components may appear; pre-processing steps like smoothing, closing, or erosion can mitigate such issues. Overall, randcomponenten describe the subset of connected components that are connected to the boundary, providing a practical distinction in analysis and processing workflows.