eprintid: 10086021 rev_number: 36 eprint_status: archive userid: 608 dir: disk0/10/08/60/21 datestamp: 2019-11-20 14:35:48 lastmod: 2021-12-14 23:35:39 status_changed: 2019-11-20 14:35:48 type: proceedings_section metadata_visibility: show creators_name: Nixon, M creators_name: Outlaw, F creators_name: MacDonald, LW creators_name: Leung, TS title: The importance of a device specific calibration for smartphone colorimetry ispublished: pub divisions: UCL divisions: B04 divisions: C05 divisions: F44 divisions: F42 note: Reprinted with permission of IS&T: The Society for Imaging Science and Technology sole copyright owners of, "CIC27: Twenty-seventh Color and Imaging Conference 2019", abstract: In order for a smartphone-based colorimetry system to be generalizable, it must be possible to account for results from multiple phones. A move from device-specific space to a device independent space such as XYZ space allows results to be compared, and means that the link between XYZ values and the physical parameter of interest needs only be determined once. We compare mapping approaches based on calibration data provided in image metadata, including the widely used open-source software dcraw, to a separate calibration carried out using a colorcard. The current version of dcraw is found to behave suboptimally with smartphones and should be used with care for mapping to XYZ. Other metadata approaches perform better, however the colorcard approach provides the best results. Several phones of the same model are compared and using an xy distance metric it is found that a device-specific calibration is required to maintain the desired precision. date: 2019-10-21 date_type: published publisher: Society for Imaging Science and Technology official_url: https://doi.org/10.2352/issn.2169-2629.2019.27.10 oa_status: green full_text_type: other language: eng primo: open primo_central: open_green verified: verified_manual elements_id: 1719209 doi: 10.2352/issn.2169-2629.2019.27.10 lyricists_name: Leung, Terence lyricists_name: Macdonald, Lindsay lyricists_name: Nixon-Hill, Miranda lyricists_name: Outlaw, Thomas lyricists_id: TSTLE21 lyricists_id: LWMAC04 lyricists_id: MNIXO69 lyricists_id: TFJOU93 actors_name: Nixon, Miranda actors_id: MNIXO69 actors_role: owner full_text_status: public series: Color and Imaging Conference publication: Color and Imaging Conference volume: 27 number: 1 place_of_pub: Paris, France pagerange: 49-54 event_title: 27th Color and Imaging Conference (CIC27) issn: 2166-9635 book_title: 27th Color and Imaging Conference Final Program and Proceedings citation: Nixon, M; Outlaw, F; MacDonald, LW; Leung, TS; (2019) The importance of a device specific calibration for smartphone colorimetry. In: 27th Color and Imaging Conference Final Program and Proceedings. (pp. pp. 49-54). Society for Imaging Science and Technology: Paris, France. Green open access document_url: https://discovery.ucl.ac.uk/id/eprint/10086021/1/CIC_Final.pdf