Bone reconstruction from stereo Xray images Reconstruction Overview

Bone reconstruction from stereo X-ray images 박노열 서울대학교

Reconstruction

Overview Statistical Shape Model Data fit term Optimizer

Overview Mahalanobis Distance PCA Pose View Point X-ray Silhou ette Canny edge Search for Closest point Optimizer 3 D distance Angle Assign value

Statistical Shape Model Mahalanobis Distance PCA Pose View Point X-ray Silhou ette Canny edge Search for Closest point Optimizer 3 D distance Angle Assign value

Principle component analysis •

Data fit term Mahalanobis Distance PCA Pose View Point X-ray Silhou ette Canny edge Search for Closest point Optimizer 3 D distance Angle Assign value

Calibration • X-Ray 이미지와 View Point 설정

Extract silhouette • View Point로부터 뼈의 실루엣 추출

Edge detection • Canny edge detector 사용 • 실루엣과 가장 가까운 Edge point매칭 – K-Nearest Neighbor algorithm 사용

Calculate distance • 두 포인트간의 3 D distance 계산

Assign energy value • 모든 Viewpoint에 대해 • 모든 실루엣의 Point에 대해

Optimizer Mahalanobis Distance PCA Pose View Point X-ray Silhou ette Canny edge Search for Closest point Optimizer 3 D distance Angle Assign value

Objective function • 결정해야 하는 Parameter – Pose parameter – Shape parameter •

Minimization strategy • Pose optimization of the mean shape • Simultaneous pose and shape Opt • Using Conjugate gradient method