IEEE Transactions on Circuits and Systems for Video Technology

We present a compressed domain scheme that is able to recognize and localize actions at high speeds. The recognition problem is posed as performing an action video query on a test video sequence. Our method is based on computing motion similarity using compressed domain features which can be extracted with low complexity. We introduce a novel motion correlation measure that takes into account diff... View full abstract»

We propose a filtering framework for multitarget tracking that is based on the probability hypothesis density (PHD) filter and data association using graph matching. This framework can be combined with any object detectors that generate positional and dimensional information of objects of interest. The PHD filter compensates for missing detections and removes noise and clutter. Moreover, this filt... View full abstract»

In this paper, a novel algorithm for parametric camera motion estimation is introduced. More particularly, a novel stochastic vector field model is proposed, which can handle smooth motion patterns derived from long periods of stable camera motion and can also cope with rapid camera motion changes and periods when the camera remains still. The stochastic vector field model is established from a se... View full abstract»

This paper addresses 2-D and 3-D active entity detection in video scenes. Active entities are the foreground parts in a stationary background scene and they typically correspond to the regions of interest in many applications such as video surveillance, object and person tracking, and suspicious object detection, among others. We present a novel framework that permits obtaining 2-D and 3-D active ... View full abstract»

Dual-camera systems have been widely used in surveillance because of the ability to explore the wide field of view (FOV) of the omnidirectional camera and the wide zoom range of the PTZ camera. Most existing algorithms require a priori knowledge of the omnidirectional camera's projection model to solve the nonlinear spatial correspondences between the two cameras. To overcome this limitation, two ... View full abstract»

Object tracking is one of the fundamental problems in computer vision and has received considerable attention in the past two decades. The success of a tracking algorithm relies on two key issues: 1) an effective representation so that the object being tracked can be distinguished from the background and other objects and 2) an update scheme of the object representation to accommodate object appea... View full abstract»

In this paper, we present a hybrid framework for articulated 3-D human motion tracking from multiple synchronized cameras with potential uses in surveillance systems. Although the recovery of 3-D motion provides richer information for event understanding, existing methods based on either deterministic search or stochastic sampling lack robustness or efficiency. We therefore propose a hybrid sample... View full abstract»

We apply the probability hypothesis density (PHD) filter to track a random number of pedestrians in image sequences. The PHD filter is implemented using particle filter. How to design importance functions of the particle PHD filter remains a challenge, especially when targets can appear, disappear, merge, or split at any time. To meet this challenge, we have modeled the targets into two categories... View full abstract»

This paper presents a methodology for analyzing multimodal and multiperspective systems for person surveillance. Using an experimental testbed consisting of two color and two infrared cameras, we can accurately register the color and infrared imagery for any general scene configuration, expanding the scope of multispectral analysis beyond the specialized long-range surveillance experiments of prev... View full abstract»

Events in surveillance video occur over many time scales, but common approaches to background subtraction and video representation are implicitly based on a single temporal scale. In this work, we derive a set of causal filters which define a temporal scale-space representation for the activity at each pixel. This scale-space can be maintained and continuously updated in real time and, for static ... View full abstract»

This paper presents a survey of trajectory-based activity analysis for visual surveillance. It describes techniques that use trajectory data to define a general set of activities that are applicable to a wide range of scenes and environments. Events of interest are detected by building a generic topographical scene description from underlying motion structure as observed over time. The scene topol... View full abstract»

This paper presents a novel approach for automatic recognition of human activities for video surveillance applications. We propose to represent an activity by a combination of category components and demonstrate that this approach offers flexibility to add new activities to the system and an ability to deal with the problem of building models for activities lacking training data. For improving the... View full abstract»

Efficiently and accurately detecting pedestrians plays a very important role in many computer vision applications such as video surveillance and smart cars. In order to find the right feature for this task, we first present a comprehensive experimental study on pedestrian detection using state-of-the-art locally extracted features (e.g., local receptive fields, histogram of oriented gradients, and... View full abstract»

This paper presents the Secure Shape and Texture SPIHT (SecST-SPIHT) scheme for secure coding of arbitrarily shaped visual objects. The scheme can be employed in a privacy protected surveillance system, whereby visual objects are encrypted so that the content is only available to authorized personnel with the correct decryption key. The secure visual object coder employs shape and texture se... View full abstract»

Automated pedestrian detection, counting, and tracking have received significant attention in the computer vision community of late. As such, a variety of techniques have been investigated using both traditional 2-D computer vision techniques and, more recently, 3-D stereo information. However, to date, a quantitative assessment of the performance of stereo-based pedestrian detection has been prob... View full abstract»

In this paper, we address the problem of privacy protection in video surveillance. We introduce two efficient approaches to conceal regions of interest (ROIs) based on transform-domain or codestream-domain scrambling. In the first technique, the sign of selected transform coefficients is pseudorandomly flipped during encoding. In the second method, some bits of the codestream are pseudorandomly in... View full abstract»