DOI QR코드

DOI QR Code

Image Restoration Considering Chromatic Aberration Problem of Multi-Spectral Filter Array Image

다중 분광 필터 배열 영상의 색수차 문제를 고려한 영상 복원 알고리즘

  • Kwon, Ji Yong (Department of Electrical and Electronic Engineering, Yonsei University) ;
  • Kang, Moon Gi (Department of Electrical and Electronic Engineering, Yonsei University)
  • 권지용 (연세대학교 전기전자공학과) ;
  • 강문기 (연세대학교 전기전자공학과)
  • Received : 2016.04.06
  • Accepted : 2016.05.02
  • Published : 2016.05.25

Abstract

To capture color and near-infrared images simultaneously, a multi-spectral filter array(MSFA) sensor is used. This is because an NIR band gives additional invisible information to human eyes to see subject under extremely low light level. However, because lenses have different refractive indices for different wavelengths, lenses may fail to focus widely different rays to the same convergence point. This is why a chromatic aberration(CA) problem occurs and images are degraded. In this paper, the image restoration algorithm for an MSFA image, which removes the CA problem, is presented. The obtained MSFA image is filtered by the estimated low-pass kernel to generate a base image. This base image is used to remove CA problem in multi-spectral(MS) images. By modeling the image degradation process and by using the least squares approach of the difference between the high-frequencies of the base and MS images, the desired high-resolution MS images are reconstructed. The experimental results show that the proposed algorithm performs well in estimating the high-quality MS images and reducing the chromatic aberration problem.

저조도 환경에서 근적외선은 사람 눈에 보이지 않는 추가적인 정보를 제공하여 물체를 보다 분명하게 구별하고 인식하도록 도움을 준다. 컬러 영상과 근적외선 영상을 동시에 획득하기 위해서 다중 분광 필터 배열을 사용하였다. 그러나 렌즈의 굴절률은 빛의 파장 길이에 따라 다르기 때문에 초점면에 상이 다르게 맺히게 된다. 그 결과 색수차 문제가 발생하고 영상은 흐려지게 되며 영상의 해상도가 떨어지게 된다. 본 논문에서는 이러한 색수차 문제를 고려한 영상 복원 알고리즘을 제안하고자 한다. 다중 분광 필터 배열 영상에 컷오프 주파수가 추정된 저주파 통과 필터를 적용하여 기반 영상을 추정하도록 하였다. 이 영상을 이용하여 다중 분광 영상의 색수차 문제가 해결된 영상을 추정하도록 하였다. 영상 획득 과정에서, 색수차 문제와 기반 영상 형성 과정을 모델링하였다. 이러한 모델을 바탕으로, 기반 영상과 다중 분광 영상 간의 고주파 성분 차이에 대한 최소 자승법을 풀어서 다중 분광 영상을 획득하도록 하였다. 실험 결과는 제안하는 알고리즘이 색수차 문제가 최소화된 고화질의 다중 분광 영상을 추정한 것을 보여준다.

Keywords

References

  1. B. Bayer, "Color imaging array," US Patent 3,971,065, 1976.
  2. K. Hirakawa and P. Wolfe, "Spatio-spectral color filter array design for optimal image recovery," IEEE Transactions on Image Processing, 17, 1876-1890, 2008. https://doi.org/10.1109/TIP.2008.2002164
  3. B. Gunturk, Y. Altunbasak, and R. Mersereau, "Color plane interpolation using alternating projections," IEEE Transactions on Image Processing, 11, 997-1013, 2002. https://doi.org/10.1109/TIP.2002.801121
  4. Hyun Mook Oh, Du Sic Yoo, and Moon Gi Kang, "Edge-Directed Color Interpolation on Disjointed Color Filter Array," Journal of The Institute of Electronics Engineers of Korea Vol. 47-SP, NO. 1, pp. 53-61, Jan 2010.
  5. I. Pekkucuksen and Y. Altunbasak, "Multiscale gradients-based color filter array interpolation," IEEE Transactions on Image Processing, 22, 157-165, 2013. https://doi.org/10.1109/TIP.2012.2210726
  6. P.-J. Lapray, X. Wang, J.-B. Thomas, and P. Gouton, "Multispectral filter arrays: Recent advances and practical implementation," Sensors 14(11), 21626, 2014. https://doi.org/10.3390/s141121626
  7. L. Miao, H. Qi, R. Ramanath, and W. Snyder, "Binary tree-based generic demosaicking algorithm for multispectral filter arrays," IEEE Transactions on Image Processing, 15, 3550-3558, 2006. https://doi.org/10.1109/TIP.2006.877476
  8. Y. Monno, M. Tanaka, and M. Okutomi, "Multispectral demosaicking using adaptive kernel upsampling," IEEE International Conference on Image Processing (ICIP), 3157-3160, 2011.
  9. K. Kidono and Y. Ninomiya, "Visibility estimation under night-time conditions using a multiband camera," IEEE Intelligent Vehicles Symposium, 1013-1018, 2007.
  10. J. H. Park and M. G. Kang, "Multispectral iris authentication system against counterfeit attack using gradient-based image fusion," Optical Engineering 46(11), 117003-117003-14, 2007. https://doi.org/10.1117/1.2802367
  11. D. Kiku, Y. Monno, M. Tanaka, and M. Okutomi, "Simultaneous capturing of rgb and additional band images using hybrid color filter array," Proc. SPIE 9023, 90230V-90230V-9, 2014.
  12. S. Koyama, Y. Inaba, M. Kasano, and T. Murata, "A day and night vision mos imager with robust photonic-crystal-based rgb-and-ir," IEEE Transactions on Electron Devices, 55(3), 754-759, 2008. https://doi.org/10.1109/TED.2007.914828
  13. J. Chang, H. Kang, and M. G. Kang, "Correction of axial and lateral chromatic aberration with false color filtering," IEEE Transactions on Image Processing, 22, 1186-1198, 2013. https://doi.org/10.1109/TIP.2012.2228489
  14. Z. Sadeghipoor, Y. M. Lu, and S. Süsstrunk, "Gradient-based correction of chromatic aberration in the joint acquisition of color and near-infrared images," Proc. SPIE 9404, 94040F-94040F-11, 2015.
  15. Du Sic Yoo, Ki Sun Song, and Moon Gi Kang, "A Deblurring Algorithm Combined with Edge Directional Color Demosaicing for Reducing Interpolation Artifacts," Journal of The Institute of Electronics Engineers of Korea Vol. 50, NO. 7, pp. 1833-1843, July 2013.
  16. L. Fang, O. Au, K. Tang, X. Wen, and H. Wang, "Novel 2-d mmse subpixel-based image down-sampling," IEEE Transactions on Circuits and Systems for Video Technology, 22, 740-753, 2012. https://doi.org/10.1109/TCSVT.2011.2179458
  17. Y. Zhang, "A new merging method and its spectral and spatial effects," International Journal of Remote Sensing 20(10), 2003-2014, 1999. https://doi.org/10.1080/014311699212317
  18. Farsiu, Sina, et al. "Fast and robust super-resolution." Image Processing, 2003. ICIP 2003. Proceedings. 2003 International Conference on. Vol. 2. IEEE, 2003.
  19. Babacan, S. Derin, Rafael Molina, and Aggelos K. Katsaggelos. "Parameter estimation in TV image restoration using variational distribution approximation." Image Processing, IEEE Transactions on 17. 3, 326-339, 2008. https://doi.org/10.1109/TIP.2007.916051
  20. R. Hardie, K. Barnard, and E. Armstrong, "Joint map registration and high-resolution image estimation using a sequence of undersampled images," IEEE Transactions on Image Processing, 6, 1621-1633, 1997. https://doi.org/10.1109/83.650116
  21. L. Fang, O. Au, K. Tang, X. Wen, and H. Wang, "Novel 2-d mmse subpixel-based image down-sampling," IEEE Transactions on Circuits and Systems for Video Technology, 22, 740-753, 2012. https://doi.org/10.1109/TCSVT.2011.2179458
  22. R. C. Gonzalez, R. E. Woods, Digital Image Processing (3rd Edition), Prentice-Hall, Inc., Upper Saddle River, NJ, USA, 2006.