Denoising Algorithm for CFA Image Sensors Considering Inter-Channel Correlation
In this paper, a spatio-spectral-temporal filter considering an inter-channel correlation is proposed for the denoising of a color filter array (CFA) sequence acquired by CCD/CMOS image sensors. Owing to the alternating under-sampled grid of the CFA pattern, the inter-channel correlation must be con...
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MDPI AG
2017-05-01
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| Series: | Sensors |
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| Online Access: | http://www.mdpi.com/1424-8220/17/6/1236 |
| _version_ | 1798038471407828992 |
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| author | Min Seok Lee Sang Wook Park Moon Gi Kang |
| author_facet | Min Seok Lee Sang Wook Park Moon Gi Kang |
| author_sort | Min Seok Lee |
| collection | DOAJ |
| description | In this paper, a spatio-spectral-temporal filter considering an inter-channel correlation is proposed for the denoising of a color filter array (CFA) sequence acquired by CCD/CMOS image sensors. Owing to the alternating under-sampled grid of the CFA pattern, the inter-channel correlation must be considered in the direct denoising process. The proposed filter is applied in the spatial, spectral, and temporal domain, considering the spatio-tempo-spectral correlation. First, nonlocal means (NLM) spatial filtering with patch-based difference (PBD) refinement is performed by considering both the intra-channel correlation and inter-channel correlation to overcome the spatial resolution degradation occurring with the alternating under-sampled pattern. Second, a motion-compensated temporal filter that employs inter-channel correlated motion estimation and compensation is proposed to remove the noise in the temporal domain. Then, a motion adaptive detection value controls the ratio of the spatial filter and the temporal filter. The denoised CFA sequence can thus be obtained without motion artifacts. Experimental results for both simulated and real CFA sequences are presented with visual and numerical comparisons to several state-of-the-art denoising methods combined with a demosaicing method. Experimental results confirmed that the proposed frameworks outperformed the other techniques in terms of the objective criteria and subjective visual perception in CFA sequences. |
| first_indexed | 2024-04-11T21:40:39Z |
| format | Article |
| id | doaj.art-c4a5d7def5554a6d85b1a2367a204b2d |
| institution | Directory Open Access Journal |
| issn | 1424-8220 |
| language | English |
| last_indexed | 2024-04-11T21:40:39Z |
| publishDate | 2017-05-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Sensors |
| spelling | doaj.art-c4a5d7def5554a6d85b1a2367a204b2d2022-12-22T04:01:36ZengMDPI AGSensors1424-82202017-05-01176123610.3390/s17061236s17061236Denoising Algorithm for CFA Image Sensors Considering Inter-Channel CorrelationMin Seok Lee0Sang Wook Park1Moon Gi Kang2School of Electrical and Electronics Engineering, Yonsei University, 50 Yonsei-Ro, Seodaemun-Gu, Seoul 03722, KoreaMedical Device Development Centre, Daegu-Gyeongbuk Medical Innovation Foundation, 80 Cheombok-Ro, Dong-gu, Daegu 41061, KoreaSchool of Electrical and Electronics Engineering, Yonsei University, 50 Yonsei-Ro, Seodaemun-Gu, Seoul 03722, KoreaIn this paper, a spatio-spectral-temporal filter considering an inter-channel correlation is proposed for the denoising of a color filter array (CFA) sequence acquired by CCD/CMOS image sensors. Owing to the alternating under-sampled grid of the CFA pattern, the inter-channel correlation must be considered in the direct denoising process. The proposed filter is applied in the spatial, spectral, and temporal domain, considering the spatio-tempo-spectral correlation. First, nonlocal means (NLM) spatial filtering with patch-based difference (PBD) refinement is performed by considering both the intra-channel correlation and inter-channel correlation to overcome the spatial resolution degradation occurring with the alternating under-sampled pattern. Second, a motion-compensated temporal filter that employs inter-channel correlated motion estimation and compensation is proposed to remove the noise in the temporal domain. Then, a motion adaptive detection value controls the ratio of the spatial filter and the temporal filter. The denoised CFA sequence can thus be obtained without motion artifacts. Experimental results for both simulated and real CFA sequences are presented with visual and numerical comparisons to several state-of-the-art denoising methods combined with a demosaicing method. Experimental results confirmed that the proposed frameworks outperformed the other techniques in terms of the objective criteria and subjective visual perception in CFA sequences.http://www.mdpi.com/1424-8220/17/6/1236color filter array image sensorspatial-temporal filtervideo denoisinginter-channel correlation |
| spellingShingle | Min Seok Lee Sang Wook Park Moon Gi Kang Denoising Algorithm for CFA Image Sensors Considering Inter-Channel Correlation Sensors color filter array image sensor spatial-temporal filter video denoising inter-channel correlation |
| title | Denoising Algorithm for CFA Image Sensors Considering Inter-Channel Correlation |
| title_full | Denoising Algorithm for CFA Image Sensors Considering Inter-Channel Correlation |
| title_fullStr | Denoising Algorithm for CFA Image Sensors Considering Inter-Channel Correlation |
| title_full_unstemmed | Denoising Algorithm for CFA Image Sensors Considering Inter-Channel Correlation |
| title_short | Denoising Algorithm for CFA Image Sensors Considering Inter-Channel Correlation |
| title_sort | denoising algorithm for cfa image sensors considering inter channel correlation |
| topic | color filter array image sensor spatial-temporal filter video denoising inter-channel correlation |
| url | http://www.mdpi.com/1424-8220/17/6/1236 |
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