Research On Performance Optimization Of DIBR

Compared with stereoscopic video,Free-Viewpoint Video(FVV)has more advantages in the aspect of immersion and interactivity,which is the key development direction of digital video application in the future.Due to the constraints of current storage and bandwidth,it is impossible to realize the efficient real-time transmission of a large number of data from FVV acquisition end to display end.As the core algorithm of FVV system,virtual viewpoint rendering method can synthesize a small number of viewpoints into more viewpoints.Depthimage-based Rendering(DIBR)has been applied in FVV system by Moving Picture Experts Group(MPEG)because of its low bandwidth increment,easy implementation,fast execution speed and high quality of image generation.There are other problems in DIBR,such as the quality of virtual viewpoints.If the problems in DIBR are solved well,high-quality visual experience can be obtained.Aiming at the above problems,this paper focuses on the performance optimization of DIBR(improving the quality of virtual viewpoints),and its main research contents and results are as follows:(1)A preprocessing method based on color correction and depth map spatial filtering is proposed to prevent the influence of the quality of reference view image on the rendering effect of virtual view.Firstly,the algorithm uses a block-based color correction method to prevent artifacts from appearing in different viewpoints due to different locations and environments.Then,the algorithm adopts a spatial filtering preprocessing method optimized by the paper to modify the error depth information in depth map.This method mainly improves the accuracy of depth map by morphological closure operation,median filtering and guided filtering.(2)An optimized forward mapping method is proposed to solve the overlap and crack problems.The algorithm is based on z-buffer and the self-applicable one for two method.Experiments show that the method can eliminate the overlap phenomenon and effectively reduce the number of cracks.An improved inverse mapping algorithm is proposed to avoid a large number of wrong crack filling in the inverse mapping.The method uses median filter and average color difference in the field to eliminate the wrong mapping points.An optimized domain background repair algorithm is proposed to improve the effect of hole repair.Experiments show that the algorithm can enhance the reliability of the weighted pixels.(3)A virtual viewpoint rendering method based on multiple reference viewpoints is proposed to improve the quality of the generated viewpoint image.Firstly,according to the distribution characteristics of the reference viewpoint,the required reference viewpoint is selected;secondly,the optimized image preprocessing method is used to preprocess the reference viewpoint image;secondly,the optimized forward mapping and mutation point elimination method are used to generate the intermediate viewpoint view;then,the improved reverse mapping method is used to eliminate the cracks;and then,the base-based image preprocessing method is used finally,the optimized domain background repair algorithm is used to repair the hole.Through experimental verification,the optimized algorithm can achieve good results in performance,and improve the quality of virtual view image and visual effect.