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Color Interpolation Algorithm for Pixel Resolution Modus of Image Sensor

영상센서의 출력 해상도 모드를 고려한 색상 보간 알고리즘

  • Kim, Bu-Gong (Department of Electronics Engineering, Korea Polytechnic University) ;
  • Kim, Moon-Cheol (Department of Electronics Engineering, Korea Polytechnic University)
  • 김부공 (한국산업기술대학교 전자공학과) ;
  • 김문철 (한국산업기술대학교 전자공학부)
  • Received : 2014.05.08
  • Accepted : 2014.09.11
  • Published : 2014.09.25

Abstract

Various interpolations for digital imaging devices with a single image sensor have proposed. However, conventional methods did not consider the resolution modus of image sensor using periodic sampling. Therefore, the resulting images have problems such as quality degradation and color artifacts(color moire, zipper). In this paper, we propose a color interpolation algorithm for pixel resolution modus of image sensor. The proposed algorithm consisted of an initial step to compensate edge prediction effectively and refinement step using minimum directions for pixel resolution modus. To analyze a result of the proposed algorithm with conventional methods, we evaluated subjectively using images quality comparison and objectively using PSNR(Peak Signal to Noise Ratio). Experimental results showed that the proposed algorithm was more successful in eliminating the color artifacts than conventional methods judged by both objective and subjective criteria.

현재까지 단일 영상센서를 사용하는 디지털 이미징 장치들을 위해 다양한 보간 기법들이 제안되어 왔다. 그러나 기존 보간 기법들은 주기적 샘플링을 사용하는 영상센서의 출력 해상도 모드를 고려하지 않았다. 따라서 출력 영상에서 해상도 화질 열화 및 color artifacts(color moire, zipper)현상들이 문제점으로 나타난다. 본 논문은 영상센서의 출력 해상도 모드를 고려한 색상 보간 알고리즘을 제안한다. 제안하는 보간 알고리즘은 효과적으로 에지 예측을 보상하는 초기단계와 해상도 모드를 고려하여 최소한의 방향성을 이용한 화질 개선단계로 구성되었다. 기존 기법들과 제안하는 알고리즘 결과를 분석 하기위해 주관적 화질비교와 PSNR(Peak Signal to Noise Ratio)을 통한 객관적 화질평가를 비교하였다. 객관적인 수치와 시각적인 부분에서 기존 기법 대비 color artifacts를 효과적으로 개선하였다.

Keywords

References

  1. B.E. Bayer, "Color imaging array," U.S. Patent 3 971 065, Jul. 1976.
  2. R. Ramanath, W.E. Synder and G.L. Bilbro, "Demosaicking methods for Bayer color array," Journal of Electronic Imaging, Vol. 11, No. 3, pp. 306-315, Jul. 2002. https://doi.org/10.1117/1.1484495
  3. B.K. Gunturk, J. Glotzbach, Y. Altunbasak, R.W. Schafer and R.M. Mersereau, "Demosaicking: color filter array interpolation," IEEE Signal Processing Magazine, Vol. 22, No. 1, pp. 44-54, Jan. 2005. https://doi.org/10.1109/MSP.2005.1407714
  4. E.N. Linzer and W. Kwok, "Digital video camera with binning or skipping correction," U.S. Patent 7 414 670 B1, Aug. 2008.
  5. P.S. Tsai, T. Acharya and A.K. Ray, "Adaptive fuzzy color interpolation," Journal of Electronic Imaging, Vol. 11, No. 3, pp. 293-305, Jul. 2002. https://doi.org/10.1117/1.1479702
  6. S.C. Pei and I.K. Tam, "Effective color interpolation in CCD color filter arrays using signal correlation," IEEE Transactions on Circuits and System for Video Technology, Vol. 13, No. 6, pp. 503-513, Jun. 2003. https://doi.org/10.1109/TCSVT.2003.813422
  7. W. Lu and Y.P. Tan, "Color filter array demosaicking: New method and performance measures," IEEE Transactions on Image Processing, Vol. 12, No. 10, pp. 1194-1210, Oct. 2003. https://doi.org/10.1109/TIP.2003.816004
  8. H.A. Chang and H. Chen, "Directionally weighted color interpolation for digital cameras," IEEE International Symposium on Circuits and Systems, Vol. 6, pp. 6284-6287, May 2005.
  9. C. Laroche and M. Prescott, "Apparatus and method for adaptively interpolating a full color image utilizing chrominance gradients," U.S. Patent 5 373 322, Dec. 1994.
  10. J.E. Adams and J.F. Hamilton, "Adaptive color plane interpolation in single sensor color electronic camera," U.S. Patent 5 652 621, Jul. 1997.
  11. D.C. Sung and H.W. Tsao, "A gradient based edge sensing scheme for color filter array demosaicking," IEEE 2dn Global Conf. on Consumer Electronics, pp. 249-252, Tokyo, Japan, Oct. 2013.
  12. J.H. Seo and Y.J. Jeong, "A New Demosaicking Algorithm for Honeycomb CFA CCD by Utilizing Color Filter Characteristics," Journal of The Institute of Electronics and Information Engineers, Vol. 48, No. 3, pp. 62-70, May 2011.
  13. K. Hirakawa and T.W. Parks, "Adaptive homogeneity-directed demosaicing algorithm," IEEE Transactions on Image Processing, Vol. 14, No. 3, pp. 360-369, Mar. 2005. https://doi.org/10.1109/TIP.2004.838691
  14. J. Lee, T. Jeong and C. Lee, "Edge-adaptive demosaicking for artifact suppression along line edges," IEEE Transactions on Consumer Electronics, Vol. 53, No. 3, pp. 1076-1083, Aug. 2007. https://doi.org/10.1109/TCE.2007.4341588
  15. L. Chang and Y.P. Tan, "Effective use of spatial and spectral correlations for color filter array demosaicking," IEEE Transactions on Consumer Electronics, Vol. 50, No. 1, pp. 355-365, Jan. 2004. https://doi.org/10.1109/TCE.2004.1277885
  16. D.S. Yoo, K.S. Song and M.G. Kang, "A Deblurring Algorithm Combined with Edge Directional Color Demosaicing for Reducing Interpolation Artifacts," Journal of The Institute of Electronics and Information Engineers, Vol. 50, No. 7, pp. 205-215, Jul. 2013. https://doi.org/10.5573/ieek.2013.50.7.205