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An EREW PRAM Algorithm for Image Component Labeling
March 1989 (vol. 11 no. 3)
pp. 258-262

An important midlevel task for computer vision is addressed. The problem consists of labeling connected components in N/sup 1/2/*N/sup 2/2/ binary images. This task can be solved with parallel computers by using a simple and novel algorithm. The parallel computing model used is a synchronous fine-grained shared-memory model where only one processor can read from or write to the same memory location at a given time. This model is known as the exclusive-read exclusive-write parallel RAM (EREW PRAM). Using this model, the algorithm presented has O(log N) complexity. The algorithm can run on parallel machines other than the EREW PRAM. In particular, it offers an optimal image component labeling algorithm for mesh-connected computers.

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Index Terms:
parallel algorithm; parallel processing; EREW PRAM algorithm; image component labeling; computer vision; binary images; synchronous fine-grained shared-memory model; exclusive-read exclusive-write parallel RAM; mesh-connected computers; computational complexity; computer vision; parallel algorithms; random-access storage
R. Cypher, J.L.C. Sanz, L. Snyder, "An EREW PRAM Algorithm for Image Component Labeling," IEEE Transactions on Pattern Analysis and Machine Intelligence, vol. 11, no. 3, pp. 258-262, March 1989, doi:10.1109/34.21794
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