Non-rigid registration with reliable distance field for dynamic shape completion

We propose a non-rigid registration method for completion of dynamic shapes with occlusion. Our method is based on the idea that an occluded region in a certain frame should be visible in another frame and that local regions should be moving rigidly when the motion is small. We achieve this with a novel reliable distance field (DF) for non-rigid registration with missing regions. We first fit a pseudo-surface onto the input shape using a surface reconstruction method. We then calculate the difference between the DF of the input shape and the pseudo-surface. We define the areas with large difference as unreliable, as these areas indicate that the original shape cannot be found nearby. We then conduct non-rigid registration using local rigid transformations to match the source and target data at visible regions and maintain the original shape as much as possible in occluded regions. The experimental results demonstrate that our method is capable of accurately filling in the missing regions using the shape information from prior or posterior frames. By sequentially processing the data, our method is also capable of completing an entire sequence with missing regions.