Raster and vector processing for scanned linework

David D. Greenlee

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Raster and vector processing for scanned linework

David D. Greenlee

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Abstract

An investigation of raster editing techniques, including thinning, filling, and node detecting, was performed by using specialized software. The techniques were based on encoding the state of the 3-by-3 neighborhood surrounding each pixel into a single byte. A prototypical method for converting the edited raster linkwork into vectors was also developed. Once vector representations of the lines were formed, they were formatted as a Digital Line Graph, and further refined by deletion of nonessential vertices and by smoothing with a curve-fitting technique.

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David D. Greenlee. 1987. Raster and vector processing for scanned linework. https://pubs.usgs.gov/publication/70142168

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