Image-based 3D Reconstruction Of Transparent Objects

Following the high-speed development of computer science,3D reconstruction which is the crossing field of computer graphics and computer vision has become a research focus for a long time.3D reconstruction techniques are extensively used in modern medical,virtual reality,intelligent navigation and cultural relic protection.Meanwhile,more flexibility and convenience of these methods are required.A 3D reconstruction method based on geometrical optics and image processing is presented here.The main work of this paper includes:build surface gradient measuring system of transparent objects,obtain gradient data by image processing,and reconstruct 3D surface using gradient data.A slope measurement system based on Snell’s law is built for measuring the surface gradient,we use a display as the light source of color template,the camera captures the projection image from the transparent object,by matching the different color regions of the projection image with the cells of color template,the optical path from each cell to projected image can be traced back,by measuring the necessary parameters,the slope of each color region can be calculated,finally we can reconstruct the 3D surface from the gradient field.We choose Fourier integral transformation method which is commonly used in the global integral technique to calculate 3D data clouds.An improved triangular growth method is presented and the solid models are rendered by software.In this paper,the concept of fuzzy recognition is introduced to match the projection image and the template image,color similarity can be calculated from fuzzy similar matrix.In addition,this paper designed a pair of mutually orthogonal color stripes as the template image,this method can improve the image sampling rate from N to N2,which greatly improve the sampling density of 3D reconstruction.Several irregularly shaped transparent objects and multi-frame water surfaces are experimented,some of the errors between the reconstructed values and the actual values are caculated,the water dynamics simulation results of the surface waves are added.Judging from the analysis of the experimental results,it shows that the 3D reconstruction method is feasible and effective for the transparent targets with thin thickness or flat bottom surface.In particular,the reconstruction results are better when the surface is smooth such as water surface.