Binary Image Thinning Algorithms R package thinr version 0.3.0 Thinning (skeletonization) algorithms for binary raster images. Provides seven algorithms behind a single dispatching function: Zhang-Suen (Zhang and Suen 1984) <doi:10.1145/357994.358023>, Guo-Hall (Guo and Hall 1989) <doi:10.1145/62065.62074>, a 2-D adaptation of Lee (Lee, Kashyap, and Chu 1994) <doi:10.1006/cgip.1994.1042>, K3M (Saeed, Tabedzki, Rybnik, and Adamski 2010) <doi:10.2478/v10006-010-0024-4>, the parallel form commonly attributed to Hilditch (1969, in 'Machine Intelligence 4'), OPTA / SPTA (Naccache and Shinghal 1984), and Holt and colleagues (1987) <doi:10.1145/12527.12531>. Also provides the medial axis transform (Blum 1967) and a distance transform implementation following Felzenszwalb and Huttenlocher (2012) <doi:10.4086/toc.2012.v008a019>. The thin() API selects the algorithm by name, defaulting to Zhang-Suen. Complements the morphology in the 'EBImage' package, which does not provide a thinning operator. Software Depends: R (>= 4.2) Imports: Rcpp LinkingTo: Rcpp Suggests: bench, covr, knitr, lintr, rmarkdown, styler, testthat (>= 3.0.0) Bill Denney <wdenney@humanpredictions.com> Comprehensive R Archive Network (CRAN) Bill Denney [aut, cre] (ORCID: <https://orcid.org/0000-0002-5759-428X>, affiliation: Human Predictions, LLC) LGPL-3 2026-07-26 application/tgz https://CRAN.R-project.org/package=thinr doi:10.32614/CRAN.package.thinr