{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,20]],"date-time":"2025-11-20T12:36:22Z","timestamp":1763642182139,"version":"build-2065373602"},"reference-count":20,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2017,2,5]],"date-time":"2017-02-05T00:00:00Z","timestamp":1486252800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"This work was supported by the National Research Foundation of Korea(NRF) grant funded by the Korea government(MEST)","award":["2015R1A2A1A14000912"],"award-info":[{"award-number":["2015R1A2A1A14000912"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In this paper, we propose a green (G)-channel restoration for a red\u2013white\u2013blue (RWB) color filter array (CFA) image sensor using the dual sampling technique. By using white (W) pixels instead of G pixels, the RWB CFA provides high-sensitivity imaging and an improved signal-to-noise ratio compared to the Bayer CFA. However, owing to this high sensitivity, the W pixel values become rapidly over-saturated before the red\u2013blue (RB) pixel values reach the appropriate levels. Because the missing G color information included in the W channel cannot be restored with a saturated W, multiple captures with dual sampling are necessary to solve this early W-pixel saturation problem. Each W pixel has a different exposure time when compared to those of the R and B pixels, because the W pixels are double-exposed. Therefore, a RWB-to-RGB color conversion method is required in order to restore the G color information, using a double-exposed W channel. The proposed G-channel restoration algorithm restores G color information from the W channel by considering the energy difference caused by the different exposure times. Using the proposed method, the RGB full-color image can be obtained while maintaining the high-sensitivity characteristic of the W pixels.<\/jats:p>","DOI":"10.3390\/s17020293","type":"journal-article","created":{"date-parts":[[2017,2,6]],"date-time":"2017-02-06T11:29:27Z","timestamp":1486380567000},"page":"293","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["G-Channel Restoration for RWB CFA with Double-Exposed W Channel"],"prefix":"10.3390","volume":"17","author":[{"given":"Chulhee","family":"Park","sequence":"first","affiliation":[{"name":"Yonsei University, Deptartment of Electrical and Electronic Engineering, 50 Yonsei-ro, Seodaemun-gu, Seoul 03722, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ki","family":"Song","sequence":"additional","affiliation":[{"name":"Yonsei University, Deptartment of Electrical and Electronic Engineering, 50 Yonsei-ro, Seodaemun-gu, Seoul 03722, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Moon","family":"Kang","sequence":"additional","affiliation":[{"name":"Yonsei University, Deptartment of Electrical and Electronic Engineering, 50 Yonsei-ro, Seodaemun-gu, Seoul 03722, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2017,2,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1260","DOI":"10.1109\/TCE.2005.1561853","article-title":"Color filter arrays: Design and performance analysis","volume":"51","author":"Lukac","year":"2005","journal-title":"IEEE Trans. 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