基于改进分段铰链变换的人体重建技术

Human body reconstruction based on improved piecewise hinge transformation

目前,基于单帧图像的人体建模还不能有效地处理手臂、衣服等对身体部位的遮挡,以及因视角带来的自我身体遮挡等复杂的遮挡问题。为此,利用SMPL模型骨骼关节分布特点,提出改进传统分段铰链变换模型的人体重建方法。该方法运用骨骼关节的精确标注确定模型变换的节点,结合图像轮廓边界约束图,提出前向分段回归概率期望最小化(FPR-PEM)的柔性配准方法。通过迭代模型对变形关节处结合薄板样条进行线性插值,保证模型表面点云形状的独立性,有效地注册各种姿势下的非刚性变形模型,较好地解决了复杂遮挡带来的重建挑战,并进行模型姿态回归调整,实现准确的人体建模。实验结果表明,方法可以有效实现精细和平滑模型的人体表面重建。

At present,existing single-image-based human body modeling methods still cannot effectively deal with the complex occlusions of body parts either due to the arms or clothes or to the changes of viewpoints.To solve this problem,using the distribution characteristics of skeletal joints in the SMPL model,we designed a human body reconstruction method by improving the traditional segmented hinge transformation model.The method uses the accurate annotation of the skeletal joints to identify the node of the model transformation and combines the image contour boundary constraint map to propose the non-rigid registration method of forward piecewise regression and probability expectation minimization(FPR-PEM).The iterative model was used to linearly interpolate the thin plate splines at the deformed joint to ensure the independence of the point cloud shape on the model surface,which effectively registered non-rigid deformation models under various postures and better solved the reconstruction challenges brought by complex occlusion.Then regression adjustments were performed with regard to the model posture so as made to achieve accurate human body modeling.Experimental results show that the proposed method works effectively to build a fine and smooth model of human body reconstruction.