Representations Xiao-Ming Fu
Outline Point cloud Signed distance field Implicit function Grid Pixel, Voxel ◇ Quad-tree, Octree Mesh Triangle, Tetrahedron Data structure Halfedge File format Obj, Off
Point cloud Xi P={P1,,PN,},pi= ER3 Zi 3D scanners A set of data points in some coordinate system
𝒫 = {𝒑1, … , 𝒑𝑁𝑣 }, 𝒑𝑖 = 𝑥𝑖 𝑦𝑖 𝑧𝑖 ∈ ℛ3 A set of data points in some coordinate system 3D scanners
Applications scanners ◇Reverse engineering Physical Part Generate Scan Data Create Mesh Finished Assembly Modeling Process Region Group
Applications scanners Digital preservation of cultural heritage sites and objects 009
Depth camera Depth camera:Kinect,RealSense,IPhone X,..... 00 (intel> XBOX 360 REALSENSE H N O L
Depth camera Ambient light sensor Speaker True Depth Camera Proximity sensor Microphone Flood Illuminator 7MP camera Infrared camera Dot projector
True Depth Camera
Depth Image Gray image:pixel represents distance from camera. Real capture by Kinect. Nearer is brighter. Nearer is darker
Gray image: pixel represents distance from camera. Nearer is brighter. Real capture by Kinect. Nearer is darker
Outline ◇Point cloud Signed distance field ◇Implicit function ◇Grid ◇Pixel,Voxel ◇Quad-tree,Octree ◇Mesh Triangle,Tetrahedron Data structure Halfedge File format ◇Obj,Off
Signed distance field The distance of a given point x from the boundary of fx)= (-d(x,as), ifx∈2 d(x,a2), ifx∈nc Contour line
Contour line Ω
