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Numerous videos are uploaded on video websites; most of them employ several kinds of camera operations for expanding FOV, emphasizing events, and expressing cinematic effect. To generate a profile of heterogeneous types of videos, an automatic video profiling method has been proposed to include both spatial and temporal information in a 2D image scroll. In this paper, we propose a uniformed scheme...
Even if the problem of human action categorization from videos has received a lot of attention during the past decade, it remains a challenging problem in operative conditions due to camera motion, occlusion, moving background, illumination changes and the variations of human appearance and postures. In this paper a new motion descriptor, based on a sparse optical flow computed by interest point tracking...
The research of gait independent of view angle has become an urgent problem to be solved for gait recognition. In this paper, we propose a gait recognition method that the subject can walk at an arbitrary angle. The gait is detected through background subtraction technique. The contour is represented by a novel approach which includes not only the spatial body contour but also the temporal information...
This work aims at detecting and tracking vehicles in in-car video. Rather than enhancing shape analysis of various vehicle types and road situations, this work focuses on vehicle and background motions because they are more general than shapes and colors of cars in various road environments. Basic features are tracked stably using corners, intensity peaks, and horizontal line segments. We use the...
The paper deals with the issue of action recognition as an application of the new 3D time-of-flight (ToF) camera, exploiting the special ability of the device to measure distances. Segmentation of moving people is straightforward from the distance information and subsequent steps of the processing chain follow in a classical way. We describe the first results on action recognition using ToF camera...
In this paper, we present a new framework for non-rigid structure from motion (NRSFM) that simultaneously addresses three significant challenges: severe occlusion, perspective camera projection, and large non-linear deformation. We introduce a concept called a model graph, which greatly reduces the computational cost of discovering groups of input images that depict consistent 3D shapes. A 3D model...
We present a practical approach for surface reconstruction of smooth mirror-like objects using sparse reflection correspondences (RCs). Assuming finite object motion with a fixed camera and un-calibrated environment, we derive the relationship between RC and the surface shape. We show that by locally modeling the surface as a quadric, the relationship between the RCs and unknown surface parameters...
This paper presents a video resizing approach that provides both efficiency and temporal coherence. Prior approaches either sacrifice temporal coherence (resulting in jitter), or require expensive spatio-temporal optimization. By assessing the requirements for video resizing we observe a fundamental tradeoff between temporal coherence in the background and shape preservation for the moving objects...
This paper investigates the optimal 3D modeling solution for making free-viewpoint video in a soccer stadium. We compare a player-billboard method and a 3D reconstructing method that exploits a shape-from-silhouette approach. To examine the influence of noise and the number of cameras used to make the free-viewpoint video, we produce a CG simulation of a soccer player in action and conduct subject-based...
We deal with the problem of detecting and identifying body parts in depth images at video frame rates. Our solution involves a novel interest point detector for mesh and range data that is particularly well suited for analyzing human shape. The interest points, which are based on identifying geodesic extrema on the surface mesh, coincide with salient points of the body, which can be classified as,...
The paper focuses on the problem of structure and motion recovery from a monocular image sequence under quasi-perspective projection model. Previous study on this problem adopts singular value decomposition (SVD) to the tracking matrix with rank constraint. The method is time consuming and does not work for incomplete data. In this paper, we propose to adopt power factorization to the problem. The...
Speech recognition and speaker detection technique from audio visual fusion information attract much attention. In the visual side information, namely lip reading area, most of recent studies are based on analyzing shape of mouth, whereas few studies are based on analyzing lip motion. However, analysis associated with mouth motion gives essential cues for obtaining utterance mechanics. Thus, as a...
When the man-machine communication system faces many users at the same time, it becomes a question that how to discover the spokesperson. In the complex environment, the noise may cause some difficulties for the robot to recognize the sound commands. To solve this question, we try to use the camera on the robot to find out the spokesperson. In this research, we propose a new image processing method...
We describe a spatio-temporal triangulation method to be used with rolling shutter cameras. We show how a single pair of rolling shutter images enables the computation of both structure and motion of rigid moving objects. Starting from a set of point correspondences in the left and right images, we introduce the velocity and shutter characteristics in the triangulation equations. This results in a...
This paper addresses the problem of human action matching in outdoor sports broadcast environments, by analysing 3D data from a recorded human activity and retrieving the most appropriate proxy action from a motion capture library. Typically pose recognition is carried out using images from a single camera, however this approach is sensitive to occlusions and restricted fields of view, both of which...
We propose an extension to the non-rigid factorisation method to solve the affine structure and motion of a deformable object, where the shape basis is selected automatically. In contrast to earlier approaches, we assume a general uncalibrated, affine camera model whereas most of the previous approaches assume a special case such as an orthographic, weak-perspective or paraperspective camera model...
The paper studies new constraints that characterize a 3D-motion field as observed from the relative motion of a camera. Such constraints are derived from the relative change in size of observed local image regions over time. To consider the image distortions that arise in a projective camera, a modified affine shape adaptation scheme is proposed for the case of blob detection, with an emphasis on...
In factorization approaches to nonrigid structure from motion, the 3D shape of a deforming object is usually modeled as a linear combination of a small number of basis shapes. The original approach to simultaneously estimate the shape basis and nonrigid structure exploited ortho-normality constraints for metric rectification. Recently, it has been asserted that structure recovery through ortho-normality...
This paper describes a new algorithm for recovering the 3D shape and motion of deformable and articulated objects purely from uncalibrated 2D image measurements using an iterative factorization approach. Most solutions to non-rigid and articulated structure from motion require metric constraints to be enforced on the motion matrix to solve for the transformation that upgrades the solution to metric...
Tracking and counting multiple humans in complex situations is challenging. The difficulties are tackled with appropriate knowledge in the form of various models in our approach. Human motion is decomposed into its global motion and limb motion. Multiple human objects were segmented and their global motions were tracked in 3D using ellipsoid human shape models. An improved method aiming to estimate...
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