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Shape Tracking with Occlusions via Coarse-to-Fine Region-Based Sobolev Descent.
IEEE Transactions on Pattern Analysis and Machine Intelligence
|September 10, 2015
Summary
This study introduces a new method for tracking object shapes in videos, even with occlusions. The technique uses a joint shape and appearance model with a novel optimization approach for improved accuracy.
Area of Science:
- Computer Vision
- Geometric Deep Learning
- 3D Reconstruction
Background:
- Object shape tracking from video is crucial for various applications.
- Existing joint shape and appearance models struggle with self-occlusions and dis-occlusions.
- Inaccurate shape detection results from the inability to adapt to new visual information.
Purpose of the Study:
- To develop a robust method for tracking object shapes in videos, specifically addressing challenges posed by self-occlusions and dis-occlusions.
- To improve the accuracy and adaptability of shape tracking models.
Main Methods:
- A joint shape and appearance model is propagated across video frames to determine object shape.
- Self-occlusions and dis-occlusions are explicitly modeled within a joint shape and appearance tracking framework.
- A coupled optimization problem is formulated, integrating self-occlusions and model propagation.
- A coarse-to-fine optimization method is derived using gradient descent on a novel infinite-dimensional Riemannian manifold with a Sobolev metric.
Main Results:
- Experiments demonstrate superior shape accuracy in videos with occlusions, dis-occlusions, complex radiance, and backgrounds.
- The proposed method effectively handles challenging scenarios that hinder traditional tracking approaches.
- The novel Riemannian manifold and Sobolev metric facilitate robust model perturbation and tracking.
Conclusions:
- Modeling self-occlusions and dis-occlusions significantly enhances shape tracking accuracy.
- The developed coarse-to-fine optimization strategy on a Riemannian manifold provides an advantageous approach for video tracking.
- This method offers a more reliable solution for object shape determination in dynamic visual environments.
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