Light field all-in-focus image fusion based on wavelet domain sharpness evaluation

XIE Yingxian; WU Yingchun; WANG Yumei; ZHAO Xianling; WANG Anhong

doi:10.13700/j.bh.1001-5965.2018.0739

Volume 45 Issue 9

Sep. 2019

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Abstract

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Journal of Beijing University of Aeronautics and Astronautics > 2019 > 45(9): 1848-1854.

Jiang Naixin, Zhang Jun, Luo Xiling, et al. ADS and multi-radar bias registration algorithm for ATC system[J]. Journal of Beijing University of Aeronautics and Astronautics, 2005, 31(01): 78-81. (in Chinese)

Citation:

XIE Yingxian, WU Yingchun, WANG Yumei, et al. Light field all-in-focus image fusion based on wavelet domain sharpness evaluation[J]. Journal of Beijing University of Aeronautics and Astronautics, 2019, 45(9): 1848-1854. doi: 10.13700/j.bh.1001-5965.2018.0739(in Chinese)

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Light field all-in-focus image fusion based on wavelet domain sharpness evaluation

doi: 10.13700/j.bh.1001-5965.2018.0739

School of Electronic and Information Engineering, Taiyuan University of Science and Technology, Taiyuan 030024, China

Funds:

National Natural Science Foundation of China 61601318

Shanxi Province Science Foundation for Youths 201601D021078

the Fund of Shanxi Key Subjects Construction

the Collaborative Innovation Center of Internet+3D Printing in Shanxi Province

Key Innovation Team of Shanxi 1331 Project

Scientific and Technological Innovation Team of Shanxi Province 201705D131025

Youth Foundation of Taiyuan University of Science and Technology 20132023

Foundation of China Scholarship Council

More Information

Corresponding author: WU Yingchun, E-mail: yingchunwu3030@foxmail.com
Received Date: 18 Dec 2018
Accepted Date: 29 Mar 2019
Publish Date: 20 Sep 2019

Abstract

Abstract

Traditional all-in-focus image fusion based on the multi-focus images which are captured by multiple-exposure of the camera. Light field camera has the ability of calculating the refocused images at any depth after a single exposure, which makes it more advantageous in all-in-focus image calculation. A light field all-in-focus image fusion method based on wavelet transform is proposed in this paper. Compared with the spatial image fusion method, the proposed method can effectively avoid the block artifacts and obtain a fused image with high quality. First, the refocused images used for the all-in-focus image calculation can be computed through shearing and projecting the 4D light field captured by the microlens-based light field camera. Then, the wavelet transform are applied to the refocused images and the high-frequency and low-frequency sub-images are extracted respectively. Finally, the balanced Laplace operator and pixel visibility function are proposed to evaluate the sharpness of the sub-image and to get a high-quality fusion image.Compared to the traditional region based sharpness evaluation function, the proposed method has a better performance. The experiment results prove the correctness and validity of the proposed method. The raw images captured by Lytro light field camera are used to calculate the all-in-focus image. Compared with the traditional image fusion methods, the visual effect is better and the quantitative indices are also improved with the proposed method.
- light field camera,
- digital refocusing,
- all-in-focus,
- wavelet transform,
- Laplace operator,
- local sharpness,
- image visibility

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References(15)

References

[1]	NG R.Light field photography with a hand-held plenoptic camera: CSTR 2005-02[R].Stanford: Stanford University, 2005.
[2]	NG R.Fourier slice photography[J].ACM Transactions on Graphics, 2005, 24(3):735-744. doi: 10.1145/1073204
[3]	TAO M W, HADAP S, MALIK J, et al.Depth from combining defocus and correspondence using light-field cameras[C]//IEEE International Conference on Computer Vision.Piscataway, NJ: IEEE Press, 2013: 673-680.
[4]	BOK Y, JEON H G, KWEON I S.Geometric calibration of microlens-based light-field cameras using line features[C]//European Conference on Computer Vision.Berlin: Springer, 2014: 47-61.
[5]	YOON Y, JEON H G, YOO D, et al.Light-field image super-resolution using convolutional neural network[J].IEEE Signal Processing Letters, 2017, 24(6):848-852. doi: 10.1109/LSP.2017.2669333
[6]	LIU J G.Smoothing filter-based intensity modulation:A spectral preserve image fusion technique for improving spatial details[J].International Journal of Remote Sensing, 2000, 21(18):3461-3472. doi: 10.1080/014311600750037499
[7]	Li S T, KANG X D, HU J W.Image fusion with guided filtering[J].IEEE Transactions on Image Processing, 2013, 22(7):2864-2875. doi: 10.1109/TIP.2013.2244222
[8]	FEICHTENHOFER C, FASSOLD H, SCHALLAUER P.A perceptual image sharpness metric based on local edge gradient analysis[J].IEEE Signal Processing Letters, 2013, 20(4):379-382. doi: 10.1109/LSP.2013.2248711
[9]	QIN X, ZHENG J, HU G, et al.Multi-focus image fusion based on window empirical mode decomposition[J].Infrared Physics & Technology, 2017, 85:251-260.
[10]	FAKHARI F, MOSAVI M R, LAJVARDI M M.Image fusion based on multi-scale transform and sparse representation:Image energy approach[J].IET Image Processing, 2017, 11(11):1041-1049. doi: 10.1049/iet-ipr.2017.0104
[11]	NAYAR S K, NAKAGAWA Y.Shape from focus[J].IEEE Transactions on Pattern Analysis and Machine Intelligence, 1994, 16(8):824-831. doi: 10.1109/34.308479
[12]	DENG C, MA W, YIN Y.An edge detection approach of image fusion based on improved Sobel operator[C]//IEEE International Congress on Image and Signal Processing.Piscataway, NJ: IEEE Press, 2011, 3: 1189-1193.
[13]	SHRIVAKSHAN G T, CHANDRASEKAR C.A comparison of various edge detection techniques used in image processing[J].International Journal of Computer Science Issues, 2012, 9(5):268-276.
[14]	YANG Y, PARK D S, HUANG S, et al.Fusion of MT and MR images using an improved wavelet based method[J].Journal of X-ray Science and Technology, 2010, 18(2):157-170.
[15]	HUANG W, JING Z.Evaluation of focus measures in multi-focus image fusion[J].Pattern Recognition Letters, 2007, 28(4):493-500. doi: 10.1016/j.patrec.2006.09.005