Computational Imaging Using Rotating Coded Aperture

In optical imaging,the characteristic of the light induced by the camera lens makes the definition of imaging with the object located at different depths to differ greatly.Image blur caused by optical imaging is still not completely solved until now.As a branch of computational photography,coded aperture technique is used to solve the depth estimation and depth-of-field extension caused by out-of-focus blur.This paper puts forward the rotating coded aperture to solve the depth estimation and all-focus image restoration,in the accuracy of the recovery results and friendly implementation of system integration,beyond the existing coded aperture imaging methods.The work and innovations of this paper are as follows:1.To study the correlation between the coded aperture mode and depth estimation and image restoration.This paper proposed the rotating coded aperture(RCA).RCA optimized the encoding mode by improving the resolution of zero-crossing,and use frequency complementary characteristics of several rotations to extend spectrum bandwidth of the imaging system,thus enhance the depth estimation accuracy and extend the depth-of-field performance.2.Put forward the optimization indictors of RCA.According to the performance requirements of depth estimation and image restoration,based on the generalized wiener deconvolution method,the optimization model of measuring coded aperture performance through maximum a posteriori probability is raised.3.Put forward a numerical algorithm for the optimization model.Firstly,the rotation angles and the encoding mode are optimized jointly by genetic algorithm to obtain the low resolution rotating coded aperture.And the resolution of the aperture is improved by the multi-scale coordinate descent method.4.Evaluate the proposed method with the traditional coded aperture capability,set synthetic test data,and construct the prototype RCA system.The evaluation results show that compared to the coded aperture pairs,rotating single aperture,rotating circular aperture,the depth estimation and depth-of-field extension performance of RCA are significantly improved.