Dense Reconstruction Algorithm of Sparse Light-field Based on Optical Flow Method
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摘要: 光场成像在三维重建、合成孔径去遮挡和全息成像等应用中具有重要作用。光场稠密重建算法能够弥补光场成像硬件的不足,实现稀疏光场的稠密重建。本文从二维光流基本原理出发,以光场双平面模型为基础,提出一种新的四维光场光流约束方程数学模型,利用该约束方程求解得到的光场光流确定新视角的位置坐标,并通过插值计算及图像反演逐点获得新坐标的强度值,最终获得高质量的新视角合成图像。实验结果表明,本文方法能够对长基线场景中的纹理、阴影及色彩等信息进行高质量重建,定量评价结果表明该算法能够完成复杂场景的光场稠密重建任务。本文算法仅适用于线性光场光流的约束以及一维视角光场的情形,后续相关研究将围绕非线性光流约束以及多维视角光场的情形展开。Abstract: Light field imaging plays a vital role in three-dimensional reconstruction, synthetic aperture de occlusion, and holographic imaging. The light field dense reconstruction algorithm can make up for the shortage of light field imaging hardware and realize the dense reconstruction of the sparse light field. Based on the basic principle of two-dimensional optical flow and the light field biplane model, a new mathematical model of a four-dimensional light field optical flow constraint equation is proposed in this paper. The position coordinates of the new viewing angle are determined by using the light field optical flow solved by the constraint equation, and the intensity values of the new coordinates are obtained point by point through interpolation calculation and image inversion, so as to finally obtain a high-quality new viewing angle synthetic images. The experimental results show that the proposed method can realize high-quality reconstruction of the texture, shadow, and color information in the extended baseline scene. The quantitative evaluation results show that the algorithm can accomplish the task of dense light field reconstruction in complex settings. This algorithm in this paper is only applicable to the case of linear optical flow constraint and one-dimensional viewing angle light field. The subsequent related research will focus on the case of nonlinear optical flow constraint and multi-dimensional viewing angle light field.
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Keywords:
- light field /
- light field reconstruction /
- LK optical flow method
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表 1 不同场景稠密光场重建PSNR值对比结果
Table 1 Comparison of PSNR values of dense light field reconstruction in different scenes
场景 Table Bicycle Town Boardgames Rosemary Vinyl 文献22算法 34.865 30.773 34.015 30.813 35.367 34.614 本文算法1*9 39.326 34.817 38.979 44.117 41.105 46.855 本文算法1*7 40.074 35.030 39.780 44.228 42.412 47.389 表 2 不同场景稠密光场重建SSIM值对比结果
Table 2 Comparison of SSIM values of dense light field reconstruction in different scenes
场景 Table Bicycle Town Boardgames Rosemary Vinyl 文献22算法 0.932 0.886 0.947 0.934 0.970 0.942 本文算法1*9 0.960 0.958 0.982 0.993 0.987 0.994 本文算法1*7 0.963 0.959 0.984 0.994 0.988 0.995 -
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