Fast Generation Of Elemental Image Array Based On Photon Mapping

The integral imaging technology was first proposed by physicist M.G.Lippmann in1908.Among stereoscopic display technologies,the three-dimensional integrated imaging is undoubtedly a promising and rapidly developing technology.It is a new three-dimensional display technology that uses elemental lens array to achieve parallax image acquisition and realize the reproduction of three-dimensional image in real space.This technology has many advantages,such as the system structure is not complex,no additional light source is needed,the viewpoint is continuous,and it can be well combined with the current image processing and transmission technology.It has a wide range of applications in the fields of medicine,biology,military and entertainment.Therefore,it has attracted extensive attention of researchers at home and abroad,and has shown great potential in the field of naked eye stereoscopic display technology.According to the different equipment used in the acquisition and reconstruction process,the integral imaging three-dimensional display system can be divided into three categories: all-optical integral imaging method,computer-aided generation of stereoscopic image array integral imaging method and computer reconstruction integral imaging method.The data sources of three-dimensional elemental image array for three-dimensional integrated imaging display are obtained by acquisition equipment,which will affect the final imaging quality and visual experience.At present,the data sources for experiments are mainly generated by computer virtual acquisition or acquired by camera array.With the further development of science and technology,the market demand for real-time acquisition and reproduction of three-dimensional space scene is more and more intense.Therefore,how to quickly realize the generation of elemental image array is an urgent technical problem.In this thesis,the generation method of elemental image array based on ray tracing is explored firstly.This method emits light from the light source to the scene,and uses ray tracing algorithm to calculate the image of each viewpoint,and finally generates the elemental image array.The disadvantage of this method is that each image needs to be calculated separately,and it takes a lot of time to calculate in the case of a large number of viewpoints.Then,the generation methods of elemental image array based on photon mapping algorithm and its improved progressive photon mapping algorithm are studied.These method emit photons from the light source to the scene,which is similar to the ray tracing algorithm,and calculate the image of each viewpoint through photon mapping algorithm.The corresponding photon image is needed for each generated image,and finally the elemental image array is generated.The disadvantage of these methods is also the needs for large quantity of time to calculate.In order to improve the generation speed of elemental image array,this thesis proposes a fast generation method of elemental image array based on photon mapping.Firstly,the photon mapping is used to generate one photon map,and the same photon map is used to generate other images of multiple viewpoints.Then,the multi-view image is converted into an elemental image array to avoid the time consumption of multiple photon map generation.In order to verify the performance of the proposed fast algorithm,this thesis compares and analyzes the display effect and time of elemental image array generated by various methods in simple scene and complex scene.Experimental results show that,compared with the elementary image array generation methods based on ray tracing and traditional phone mapping,the proposed method improves the generation speed of the elementary image array,especially the generation speed of multiple elementary images while ensuring the quality of the generation.