Two Strategies to Speed up Connected Component LabelingAlgorithms
Abstract
This paper presents two new strategies to speed up connectedcomponent labeling algorithms. The first strategy employs a decisiontreeto minimize the work performed in the scanning phase of connectedcomponent labeling algorithms. The second strategy uses a simplifiedunionfind data structure to represent the equivalence information amongthe labels. For 8connected components in atwodimensional (2D) image,the first strategy reduces the number of neighboring pixels visited from4 to7/3 on average. In various tests, using a decision tree decreases thescanning time by a factor of about 2. The second strategy uses a compactrepresentation of the unionfind data structure. This strategysignificantly speeds up the labeling algorithms. We prove analyticallythat a labeling algorithm with our simplified unionfind structure hasthe same optimal theoretical time complexity as do the best labelingalgorithms. By extensive experimental measurements, we confirm theexpected performance characteristics of the new labeling algorithms anddemonstrate that they are faster than other optimal labelingalgorithms.
 Authors:
 Publication Date:
 Research Org.:
 Ernest Orlando Lawrence Berkeley NationalLaboratory, Berkeley, CA (US)
 Sponsoring Org.:
 USDOE Director. Office of Science. Advanced ScientificComputing Research
 OSTI Identifier:
 929013
 Report Number(s):
 LBNL59102
R&D Project: 429201; BnR: KJ0101030; TRN: US200811%%475
 DOE Contract Number:
 DEAC0205CH11231
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Pattern Analysis Application; Journal Volume: 0; Journal Issue: 0; Related Information: Journal Publication Date: 12/23/2007
 Country of Publication:
 United States
 Language:
 English
 Subject:
 99; ALGORITHMS; PERFORMANCE; TREES; VELOCITY; Connected component labeling optimization unionfind algorithmdecision tree equivalence relation
Citation Formats
Wu, Kesheng, Otoo, Ekow, and Suzuki, Kenji. Two Strategies to Speed up Connected Component LabelingAlgorithms. United States: N. p., 2005.
Web.
Wu, Kesheng, Otoo, Ekow, & Suzuki, Kenji. Two Strategies to Speed up Connected Component LabelingAlgorithms. United States.
Wu, Kesheng, Otoo, Ekow, and Suzuki, Kenji. Sun .
"Two Strategies to Speed up Connected Component LabelingAlgorithms". United States.
doi:. https://www.osti.gov/servlets/purl/929013.
@article{osti_929013,
title = {Two Strategies to Speed up Connected Component LabelingAlgorithms},
author = {Wu, Kesheng and Otoo, Ekow and Suzuki, Kenji},
abstractNote = {This paper presents two new strategies to speed up connectedcomponent labeling algorithms. The first strategy employs a decisiontreeto minimize the work performed in the scanning phase of connectedcomponent labeling algorithms. The second strategy uses a simplifiedunionfind data structure to represent the equivalence information amongthe labels. For 8connected components in atwodimensional (2D) image,the first strategy reduces the number of neighboring pixels visited from4 to7/3 on average. In various tests, using a decision tree decreases thescanning time by a factor of about 2. The second strategy uses a compactrepresentation of the unionfind data structure. This strategysignificantly speeds up the labeling algorithms. We prove analyticallythat a labeling algorithm with our simplified unionfind structure hasthe same optimal theoretical time complexity as do the best labelingalgorithms. By extensive experimental measurements, we confirm theexpected performance characteristics of the new labeling algorithms anddemonstrate that they are faster than other optimal labelingalgorithms.},
doi = {},
journal = {Pattern Analysis Application},
number = 0,
volume = 0,
place = {United States},
year = {Sun Nov 13 00:00:00 EST 2005},
month = {Sun Nov 13 00:00:00 EST 2005}
}

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