Research On Realistic Light Field Image Rendering Technology Based On Bidirectional Reflection Distribution Function

The optical field display system(OFDS),has attracted widespread attention because of its broad application prospects.Beside the advantage of continuous viewpoints,horizontal and vertical parallaxes can be simultaneously observed in OFDS.Virtual light field acquisition is the main source of light field display contents.Especially,high-quality 3D display effect can be provide by the virtual light field acquisition based on ray tracing.In the thesis,a realistic light field image rendering method was designed based on the ray tracing algorithm and bidirectional reflection distribution function(BRDF).This method can improve the rendering quality of the model and make the output image closer to the natural.Combined with existing light field rendering algorithms,the realistic light field image rendering method was integrated in light field content production platform,which provided a solution for realistic light field rendering.The main research contents and technical innovations are summarized as follows:Firstly,the research realistic light field rendering and BRDF were introduced.The utilization of BRDF in realistic light field rendering,the physical meaning of BRDF,empirical and physical model of BRDF and measurement of BRDF were demonstrated in the thesis.It was concluded that the use of BRDF in light field rendering can theoretically improve the quality of light field rendering by analyzing the advantages and disadvantages of different technologies.Secondly,a BRDF construction method based on the measurement data was realized by combining the key advantages of real reflection information of objects in the measurement data with BRDF analysis model.The OSL shading language was used to implement the realistic light field image rendering algorithm,which provided a method for the rapid expansion of materials in the light field content production platform.Simultaneously,the similarity of the energy distribution between the measurement data and the BRDF model was as high as 90%,which can excellently restore reflective condition of current situation.Finally,Combined with rendering pipeline in the existing light field content production platform,BRDF model,based on the measurement data,can obtain more realistic rendering results.Although the original rendering method can capture real-time rendering,it lacks realism.The method was proposed in this thesis not only obtained realistic rendering,but also avoided memory overhead which caused by direct using measurement data.In summary,the realistic photo field image rendering method based on BRDF was designed and analyzed in this thesis.Implementation solution was provided for realistic photo field rendering of light field display contents and achieved the goal that render realistic photo field image.