The Design And Implementation Of The Large-scale Spherical Screen Display System

In recent years,people's material expectations and spiritual needs have been increasing,while material and cultural levels being continuously improved.More and more entertainment and popular science places have appeared,such as theme parks,playgrounds,science and technology museums,etc.With the development of 3D animation,virtual reality and other technologies,a variety of amusement facilities,such as experiential interactive cinemas,have become popular in these venues and are widely welcomed by visitors.But the screens of common facilities such as XD theaters,flying theaters,etc.are usually cylindrical or hemispherical.In recent years,Panoramic Cinema has become a popular project for theme parks,playgrounds,science museums and other places because of its gorgeous and beautiful pictures which provide users with a true 360-degree viewing experience.Generally speaking,panoramic dome theaters occupy a relatively large area.Compared with ring screen theaters or hemispherical screen theaters,the spherical screen system has large area,so 16 high-definition engineering projectors are required for splicing projection.Its playback system are different from existing theater playback systems because of the demand of high resolution quality and real-time.At present,the panoramic dome theaters playback systems are mainly developed by foreign countries.According to the needs of domestic internship companies,a large-scale spherical screen display system is designed in this paper.The large-scale spherical screen display system run in a specific hardware environment,the dome theater which has large-scale spherical screen.Through the processing of the image by cutting,deformation,and stitching,the distortion caused by the irregular curved screen is eliminated.At the same time,the system should also have a playback control center to provide convenient control and a simple,friendly interactive interface.In this paper,the requirements analysis,outline design and detailed design of the large-scale spherical screen display system are first performed.In the system requirements analysis,this article introduces the basic overview of the system,uses the case analysis method to conduct a requirements analysis,and then describes the system according to functional and non-functional requirements.In the outline design of the system,this paper analyzes and discusses the overall architecture and functional structure of the system.In the detailed design of the system,the paper firstly introduced the logical design of the system and the system flowchart,and then the main functions in the system are introduced in detail.Based on the previous analysis and design,the system was implemented.Finally,this article conducted a system test to test the basic performance of the display system.The large-scale spherical screen display system designed and implemented in this paper is suitable for a 14-meter diameter dome theaters which can accommodate about 30 people to visit at the same time.Due to its large size,the theater has higher requirements for the definition of the video source,so the calculation pressure is greater.The system can play high-definition video with a resolution of 4000*4000,perform real-time screen deformation processing based on the stitching data of the projectors,so that the audience will have excellent viewing experience.In addition,due to the large volume of the dome,multiple computers play at the same time in the system.For this,the system has a synchronous mechanism.The system also has a central control terminal with a friendly interactive interface.The theater administrator can preview the content from the central control terminal.By this way,the administrator can handle system affairs without entering the dome.This large-scale spherical screen display system uses the C/S architecture and is divided into two parts:the central control terminal and playback terminals.The central control terminal is responsible for the interaction with the user and the control of playback terminals.It provides a human-computer interaction interface,which has function of timeline,preview of videos,and media file list.The timeline function shows the playlist of the system,which is convenience for users.The function of media preview enables users who are system administrators to obtain what is playing on the screen without entering the dome.The media file list enumerates the files which are available in the system,and filters the local files to prevent unavailable files from entering the system.The playback terminals processes the projected image and then play it.There are playback terminals in the system,which run on four hosts and play in parallel.The central control terminal and the playback terminals are connected through a local area network,and the communication data is in JSON language formatBecause the screen of the system is an irregular curved screen,the projected image will be seriously distorted,so image distortion correction is necessary.At the same time,since multiple projectors have overlapping projection ranges on the screen,it is necessary to correct the brightness of the projected image.This article describes how to pre-process the initial projector parameters to obtain the data required for image distortion correction;and introduces the design and implementation of the system's real-time image distortion stitching method.