{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,10]],"date-time":"2026-02-10T18:39:34Z","timestamp":1770748774267,"version":"3.50.0"},"reference-count":32,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2022,4,26]],"date-time":"2022-04-26T00:00:00Z","timestamp":1650931200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"US Government","award":["H98230-19-D00030006"],"award-info":[{"award-number":["H98230-19-D00030006"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Information"],"abstract":"<jats:p>In this paper, we show how volume rendering with a Programmable Transfer Function can be used for the effective and comprehensible visualization of WiFi signals. A traditional transfer function uses a low-dimensional lookup table to map the volumetric scalar field to color and opacity. In this paper, we present the concept of a Programmable Transfer Function. We then show how generalizing traditional lookup-based transfer functions to Programmable Transfer Functions enables us to leverage view-dependent and real-time attributes of a volumetric field to depict the data variations of WiFi surfaces with low and high-frequency components. Our Programmable Transfer Functions facilitate interactive knowledge discovery and produce meaningful visualizations.<\/jats:p>","DOI":"10.3390\/info13050224","type":"journal-article","created":{"date-parts":[[2022,4,26]],"date-time":"2022-04-26T11:45:55Z","timestamp":1650973555000},"page":"224","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Visualization of WiFi Signals Using Programmable Transfer Functions"],"prefix":"10.3390","volume":"13","author":[{"given":"Alexander","family":"Rowden","sequence":"first","affiliation":[{"name":"Graphics and Visual Informatics Laboratory, Department of Computer Science, University of Maryland College Park, College Park, MD 20740, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Eric","family":"Krokos","sequence":"additional","affiliation":[{"name":"United States Department of Defense, 1400 Defense Pentagon, Washington, DC 20301-1400, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kirsten","family":"Whitley","sequence":"additional","affiliation":[{"name":"United States Department of Defense, 1400 Defense Pentagon, Washington, DC 20301-1400, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Amitabh","family":"Varshney","sequence":"additional","affiliation":[{"name":"Graphics and Visual Informatics Laboratory, Department of Computer Science, University of Maryland College Park, College Park, MD 20740, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,4,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Kokkinos, V., Stamos, K., Kanakis, N., Baumann, K., Wilson, A., and Healy, J. 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