Research Of Light Field Three-dimensional Imaging Technology

The research contents of this paper are supported by the National High Technology Research and Development Program of China?? Multi-mode True 3D New Display System and Device?Grant No.2012AA011903?as well as Postgraduate Research Innovation Projects of Jiangsu Province of China?? Multi-view Autostereoscopic Display System Integrated with Real-time Acquisition and Transmission?Grant No.CXLX 13₁58?.Light field three-dimensional?3D?imaging technology,which was proposed several years ago,is one of the novel 3D imaging technology.This technology has the ability to record or rebuild the spatial characteristics of the 3D objects,also can reflect the occlusion relationship between different objects.Therefore,light field 3D imaging technology,which can be widely applied in glasses-free 3D display,refocus,3D reconstruction and virtual?augmented?reality,is very in line with the human vision and has important research significance.This paper focuses on studying light field 3D imaging technology,which mainly consists of light field acquisition,light field 3D display,and multi-view 3D reconstruction.Two light field 3D display systems have been set up.Meanwhile,compressive light field computational imaging and light field multi-view 3D reconstruction are studied in the paper.This paper started on light field 3D display.The principle of light field 3D display is stated,and two light field 3D display systems based on micro-lens stripe array screen and holographic directional diffuser screen respectively are set up.Both two display systems can achieve light field 3D displays of real scene and virtual scene.The basic structure,hardware elements and principle of light field reappearing are introduced.Furthermore,the generation method of projective image,which is used for light field 3D display of holographic directional diffuser screen,has been analyzed in detail.The algorithms of image correction used on light field acquisition and light field display are proposed,which can solve the prombles of view filed inconsistency and projective image anomaly.The feasibility of our light field 3D display systems has been proved from the experiment analysis.In view of the problem of camera array acquisition with high hardware cost and big volume,a method of light field acquisition and reconstruction based on mask is developed.A light field acquisition model is constructed,in which light field imaging process is analyzed in Fourier domain.A random mask has been used to encode the light field to obtain a coded sensor image.The training method of overcomplete light fielddictionary and light field restoring algorithm are discussed.The original light field was restored from the coded sensor image and the dictionary by nonlinear optimization.Another method of compressive light field computational imaging is presented,where compressive sensing is applied to restore dense light field from sparse light field viewpoints which captured by camera array.This method can solve some problems existing in compressive light field camera like small FOV,low light transmission and mask fixing problem.The two methods of compressive light field computational imaging above provide a new thinking for light field acquisition.A real-time 3D surface reconstruction system based on multi-view of light field is set up.This system has achieved real-time 3D surface reconstruction of scene,which can make up the insufficient that traditional 2D image can not explain the 3D scene well.The imaging model of camera and the traditional camera calibration method are introduced.Multiple camera calibration is realized based on Zhang's plane calibration algorithm.In addition,the key techniques of multi-view stereo matching are discussed in detail.An improved method for multi-view stereo matching is presented,in which the matching cost accumulation is added on traditional planar scanning algorithm,so that the reconstruction system can also do well in some scenes where the texture is not rich.Moreover,a global optimization method based on the primal-dual algorithm in the form of parallel computing is used to make the reconstruction system high-quality and real-time.Several experiments on real-time reconstruction ensure the proposed reconstruction system correct.Specially,the reconstructed results have been displayed so that realizing the integration of light field acquisition,3D reconstruction and light field display technologies into a seamless system effectively.All research content of this paper is summarized in the end.Based on the deficiency of existing research,the follow-up research work has been put forward.