Figure - PMC

Skip to main content

An official website of the United States government

Here's how you know

Here's how you know

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you've safely connected to the .gov website. Share sensitive information only on official, secure websites.

View full-text article in PMC

. 2021 Jan 19;12:458. doi: 10.1038/s41467-020-20730-y

Search in PMC
Search in PubMed
View in NLM Catalog
Add to search

© The Author(s) 2021

Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.

PMC Copyright notice

Fig. 1 — a Contour of an illustrative shape. Nodes (blue) are placed equidistantly along the contour and used to create a visibility graph. Two nodes are connected in the visibility graph if they can “see each other”, i.e., the segment connecting them does not cross or align with the contour (teal edge); otherwise, the nodes cannot see each other (orange edge). The edges between nodes can be weighted according to their edge length (Euclidean distance d_E). b Visualization of the visibility graph for the cell in (a). c Heatmap of the weighted and scaled adjacency matrix of the visibility graph (a), where edges with a weight of zero indicate the absence of said edge, thus indicating “non-visibility” between the nodes. The weighted visibility graph is used for local feature extraction, while the unweighted graph is used for global shape description and shape comparison. Source data are provided as a Source Data file.