Related Experiment Video
Updated: Jul 6, 2026
05:33
Three-Dimensional Shape Modeling and Analysis of Brain Structures
Published on: November 14, 2019
Nonrigid structure-from-motion: estimating shape and motion with hierarchical Priors
Lorenzo Torresani1, Aaron Hertzmann, Chris Bregler
1Microsoft Research, Cambridge, CB3 0FB, UK. ltorre@microsoft.com
Summary
This study introduces a novel method to reconstruct non-rigid 3D object shape and motion from 2D video. The approach uses Probabilistic Principal Components Analysis (PPCA) for robustly handling missing data and modeling temporal dynamics.
Area of Science:
- Computer Vision
- 3D Reconstruction
- Non-rigid Object Analysis
Background:
- Recovering 3D shape and motion from uncalibrated 2D data is challenging.
- Modeling non-rigid deformations requires robust assumptions and techniques.
Purpose of the Study:
- To develop a method for estimating time-varying 3D shape and motion of non-rigid objects from uncalibrated 2D point tracks.
- To create a robust system capable of handling missing data and modeling temporal dynamics in object shape.
Main Methods:
- Utilizing a Probabilistic Principal Components Analysis (PPCA) shape model.
- Developing an estimation algorithm that simultaneously reconstructs 3D shape and motion.
- Incorporating temporal dynamics modeling for enhanced robustness.
Main Results:
- Successful recovery of time-varying shape and motion from 2D point tracks.
- Robust handling of missing data points through PPCA and temporal modeling.
- Accurate estimation of facial deformation models from video.
Conclusions:
- The proposed PPCA-based method effectively reconstructs non-rigid 3D object dynamics.
- The approach offers robustness against missing data and models temporal shape variations.
- This technique advances the field of 3D reconstruction from uncalibrated video sources.
Related Concept Videos
01:22Planar Rigid-Body Motion
Understanding the movement of a rigid body in planar motion involves recognizing that every particle within this body is traversing a path that maintains a consistent distance from a specific plane. This concept is fundamental in the study of physics and mechanical engineering, and it allows us to comprehend better how objects move in space.
Planar motion is typically divided into three distinct categories. The first is rectilinear translation, demonstrated by a subway train that moves along...
Planar motion is typically divided into three distinct categories. The first is rectilinear translation, demonstrated by a subway train that moves along...
01:23Curvilinear Motion: Rectangular Components
Curvilinear motion characterizes the movement of a particle or object along a curved path, notably evident when envisioning a car navigating a winding road. If the car starts at point A, its position vector is established within a fixed frame of reference, where the ratio of the position vector to its magnitude signifies the unit vector pointing in the position vector's direction.
As the car advances, its position evolves over time. Quantifying the car's velocity involves computing the time...
As the car advances, its position evolves over time. Quantifying the car's velocity involves computing the time...
01:25Relative Motion Analysis using Rotating Axes
Consider a component AB undergoing a linear motion. Along with a linear motion, point B also rotates around point A. To comprehend this complex movement, position vectors for both points A and B are established using a stationary reference frame.
However, to express the relative position of point B relative to point A, an additional frame of reference, denoted as x'y', is necessary. This additional frame not only translates but also rotates relative to the fixed frame, making it instrumental in...
However, to express the relative position of point B relative to point A, an additional frame of reference, denoted as x'y', is necessary. This additional frame not only translates but also rotates relative to the fixed frame, making it instrumental in...
01:29Relative Motion Analysis using Rotating Axes-Problem Solving
Consider a crane whose telescopic boom rotates with an angular velocity of 0.04 rad/s and angular acceleration of 0.02 rad/s2. Along with the rotation, the boom also extends linearly with a uniform speed of 5 m/s. The extension of the boom is measured at point D, which is measured with respect to the fixed point C on the other end of the boom. For the given instant, the distance between points C and D is 60 meters.
Here, in order to determine the magnitude of velocity and acceleration for point...
Here, in order to determine the magnitude of velocity and acceleration for point...
01:20Structural Classification of Joints
Joints, also known as articulations, are classified based on their structural characteristics, i.e., based on whether the articulating surfaces of the adjacent bones are directly connected by fibrous connective tissue or cartilage, or whether the articulating surfaces contact each other within a fluid-filled joint cavity. These differences serve to divide the joints of the body into three structural classifications.
A fibrous joint is where the adjacent bones are united by fibrous connective...
A fibrous joint is where the adjacent bones are united by fibrous connective...
01:30Kinematic Equations for Rotation
In mechanics, when one observes a rigid body in rotational motion with constant angular acceleration, it is possible to establish equations for its rotational kinematics. This process resembles how linear kinematics are dealt with in simpler motion studies.
For instance, imagine a point A on a rigid body engaged in circular motion. The translational velocity of this particular point can be calculated by taking the time derivatives of the displacement equation, which essentially measures the...
For instance, imagine a point A on a rigid body engaged in circular motion. The translational velocity of this particular point can be calculated by taking the time derivatives of the displacement equation, which essentially measures the...