Non-Contact Oxygen Saturation Measurement Using YCgCr Color Space with an RGB Camera
Oxygen saturation (SPO<sub>2</sub>) is an important indicator of health, and is usually measured by placing a pulse oximeter in contact with a finger or earlobe. However, this method has a problem in that the skin and the sensor must be in contact, and an additional light source is requi...
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| Format: | Article |
| Language: | English |
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MDPI AG
2021-09-01
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| Series: | Sensors |
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| Online Access: | https://www.mdpi.com/1424-8220/21/18/6120 |
| _version_ | 1797517285897797632 |
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| author | Na Hye Kim Su-Gyeong Yu So-Eui Kim Eui Chul Lee |
| author_facet | Na Hye Kim Su-Gyeong Yu So-Eui Kim Eui Chul Lee |
| author_sort | Na Hye Kim |
| collection | DOAJ |
| description | Oxygen saturation (SPO<sub>2</sub>) is an important indicator of health, and is usually measured by placing a pulse oximeter in contact with a finger or earlobe. However, this method has a problem in that the skin and the sensor must be in contact, and an additional light source is required. To solve these problems, we propose a non-contact oxygen saturation measurement technique that uses a single RGB camera in an ambient light environment. Utilizing the fact that oxygenated and deoxygenated hemoglobin have opposite absorption coefficients at green and red wavelengths, the color space of photoplethysmographic (PPG) signals recorded from the faces of study participants were converted to the YCgCr color space. Substituting the peaks and valleys extracted from the converted Cg and Cr PPG signals into the Beer–Lambert law yields the SPO<sub>2</sub> via a linear equation. When the non-contact SPO<sub>2</sub> measurement value was evaluated based on the reference SPO<sub>2</sub> measured with a pulse oximeter, the mean absolute error was 0.537, the root mean square error was 0.692, the Pearson correlation coefficient was 0.86, the cosine similarity was 0.99, and the intraclass correlation coefficient was 0.922. These results confirm the feasibility of non-contact SPO<sub>2</sub> measurements. |
| first_indexed | 2024-03-10T07:13:37Z |
| format | Article |
| id | doaj.art-8c65af26f15f4961a8a5c864901ab5f4 |
| institution | Directory Open Access Journal |
| issn | 1424-8220 |
| language | English |
| last_indexed | 2024-03-10T07:13:37Z |
| publishDate | 2021-09-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Sensors |
| spelling | doaj.art-8c65af26f15f4961a8a5c864901ab5f42023-11-22T15:11:56ZengMDPI AGSensors1424-82202021-09-012118612010.3390/s21186120Non-Contact Oxygen Saturation Measurement Using YCgCr Color Space with an RGB CameraNa Hye Kim0Su-Gyeong Yu1So-Eui Kim2Eui Chul Lee3Department of AI & Informatics, Graduate School, Sangmyung University, Seoul 03016, KoreaDepartment of AI & Informatics, Graduate School, Sangmyung University, Seoul 03016, KoreaDepartment of AI & Informatics, Graduate School, Sangmyung University, Seoul 03016, KoreaDepartment of Human-Centered Artificial Intelligence, Sangmyung University, Seoul 03016, KoreaOxygen saturation (SPO<sub>2</sub>) is an important indicator of health, and is usually measured by placing a pulse oximeter in contact with a finger or earlobe. However, this method has a problem in that the skin and the sensor must be in contact, and an additional light source is required. To solve these problems, we propose a non-contact oxygen saturation measurement technique that uses a single RGB camera in an ambient light environment. Utilizing the fact that oxygenated and deoxygenated hemoglobin have opposite absorption coefficients at green and red wavelengths, the color space of photoplethysmographic (PPG) signals recorded from the faces of study participants were converted to the YCgCr color space. Substituting the peaks and valleys extracted from the converted Cg and Cr PPG signals into the Beer–Lambert law yields the SPO<sub>2</sub> via a linear equation. When the non-contact SPO<sub>2</sub> measurement value was evaluated based on the reference SPO<sub>2</sub> measured with a pulse oximeter, the mean absolute error was 0.537, the root mean square error was 0.692, the Pearson correlation coefficient was 0.86, the cosine similarity was 0.99, and the intraclass correlation coefficient was 0.922. These results confirm the feasibility of non-contact SPO<sub>2</sub> measurements.https://www.mdpi.com/1424-8220/21/18/6120oxygen saturationYCgCr color spacehemoglobinBeer-Lambert lawphotoplethysmographic signal |
| spellingShingle | Na Hye Kim Su-Gyeong Yu So-Eui Kim Eui Chul Lee Non-Contact Oxygen Saturation Measurement Using YCgCr Color Space with an RGB Camera Sensors oxygen saturation YCgCr color space hemoglobin Beer-Lambert law photoplethysmographic signal |
| title | Non-Contact Oxygen Saturation Measurement Using YCgCr Color Space with an RGB Camera |
| title_full | Non-Contact Oxygen Saturation Measurement Using YCgCr Color Space with an RGB Camera |
| title_fullStr | Non-Contact Oxygen Saturation Measurement Using YCgCr Color Space with an RGB Camera |
| title_full_unstemmed | Non-Contact Oxygen Saturation Measurement Using YCgCr Color Space with an RGB Camera |
| title_short | Non-Contact Oxygen Saturation Measurement Using YCgCr Color Space with an RGB Camera |
| title_sort | non contact oxygen saturation measurement using ycgcr color space with an rgb camera |
| topic | oxygen saturation YCgCr color space hemoglobin Beer-Lambert law photoplethysmographic signal |
| url | https://www.mdpi.com/1424-8220/21/18/6120 |
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