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Light Field Angular Super-Resolution Algorithm Using Dilated Convolutional Neural Network with Residual Network

잔차 신경망과 팽창 합성곱 신경망을 이용한 라이트 필드 각 초해상도 기법

  • Kim, Dong-Myung (School of Electronics Engineering, Chung-Buk National University) ;
  • Suh, Jae-Won (School of Electronics Engineering, Chung-Buk National University)
  • Received : 2020.10.16
  • Accepted : 2020.10.29
  • Published : 2020.12.31

Abstract

Light field image captured by a microlens array-based camera has many limitations in practical use due to its low spatial resolution and angular resolution. High spatial resolution images can be easily acquired with a single image super-resolution technique that has been studied a lot recently. But there is a problem in that high angular resolution images are distorted in the process of using disparity information inherent among images, and thus it is difficult to obtain a high-quality angular resolution image. In this paper, we propose light field angular super-resolution that extracts an initial feature map using an dilated convolutional neural network in order to effectively extract the view difference information inherent among images and generates target image using a residual neural network. The proposed network showed superior performance in PSNR and subjective image quality compared to existing angular super-resolution networks.

마이크로렌즈 어레이 기반의 카메라로 촬영된 라이트필드 영상은 낮은 공간해상도 및 각해상도로 인하여 실제 사용하기에는 많은 제약이 따른다. 고해상도의 공간해상도 영상은 최근 많이 연구되고 있는 단일 영상 초해상도 기법으로 쉽게 얻을 수 있으나 고해상도의 각해상도 영상은 영상사이에 내재된 시점차 정보를 이용하는 과정에서 왜곡이 발생하여 좋은 품질의 각해상도 영상을 얻기 힘든 문제가 있다. 본 논문에서는 영상 사이에 내재된 시점차 정보를 효과적으로 추출하기 위해서 팽창 합성곱 신경망을 이용하여 초기 특징맵을 추출하고 잔차 신경망으로 새로운 시점 영상을 생성하는 라이트 필드 각 초해상도 영상 기법을 제안한다. 제안하는 네트워크는 기존의 각 초해상도 네트워크와 비교하여 PSNR 및 주관적 화질 비교에서 우수한 성능을 보였다.

Keywords

References

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