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Displaying 76 - 100 of 125

Scanning the Issue Smart Grid: The Electric Energy System of the Future

June 1, 2011
Author(s)
Hamid Gharavi
This is an editorial article for a special issue on smart grid. The main objective is to report on some, if not all, of smart grid future technical challenges. While acknowledging its limited coverage, this issue offers a wide range of interesting

Selective Pixel Interpolation for Spatial Error Concealment

June 1, 2011
Author(s)
Hamid Gharavi, Yi Ge, Bo Yan, Kairan Sun
This paper proposes an effective algorithm for spatial error concealment with accurate edge detection and partitioning interpolation. Firstly, a new method is used for detecting possible edge pixels and their matching pixels around the lost block. Then

Multigate Mesh Routing for Smart Grid Last Mile Communications

May 1, 2011
Author(s)
Hamid Gharavi, Bin Hu
One of the most important issues in Smart Grid is to provide consumers with the knowledge of their energy usage, as well as allowing the utility to monitor and control the electric system components with real time status. This would require the design of a

Efficient Motion Vector Interpolation for Error Concealment of H.264/AVC

March 1, 2011
Author(s)
Hamid Gharavi
In video communications the compressed video stream is very likely to be corrupted by channel errors. In order to combat these channel errors, many methods have been proposed. In this paper, a new method for motion vectors (MVs) interpolation with the help

PYRAMID MODEL BASED DOWN-SAMPLING FOR IMAGE INPAINTING

September 2, 2010
Author(s)
Hamid Gharavi
Image inpainting is a useful and powerful technique for automatically restoring or removing objects in films and damaged pictures. In the last ten years, many excellent inpainting algorithms have been proposed after Bertalmio et al. [1]. However, no paper

Asynchronous Cooperative MIMO Systems using A Linear Dispersion Structure

February 2, 2010
Author(s)
Hamid Gharavi
In this treatise, we propose a novel family of Asynchronous Cooperative Linear Dispersion Codes (ACLDCs),which is capable of maintaining full diversity in cooperative scenarios even at the presence of asynchronous reception. The linear dispersion structure

A Hybrid Frame Concealment Algorithm for H.264/AVC

January 5, 2010
Author(s)
Hamid Gharavi
In packet-based video transmissions, packets loss due to channel errors may result in the loss of the whole video frame. Recently, many error concealment algorithms have been proposed in order to combat channel errors, however most of the existing

EDITOR IN CHIEF (EIC) MESSAGE

January 1, 2010
Author(s)
Hamid Gharavi
This Editor In Chief's (EIC) message is expected to appear in the January, 2010 issue of the IEEE Transactions on CAS for Video Technology (TCSVT). The editorial team will be under the leadership of the new EIC for a period of two years.

Trends in Multimedia Communications Over Mobile Networks

November 3, 2009
Author(s)
Hamid Gharavi
Increasing demand for high quality multimedia services has been a driving factor in the technological evolution of high bandwidth wireless/mobile communications systems and standards. The most challenging aspect is the support of higher quality video

Directional Antenna for Multipath Ad Hoc Routing

October 15, 2008
Author(s)
Hamid Gharavi, Bin Hu
Multipath routing can be effectively used to maximize the utilization of network resources for real-time traffic. In mobile ad-hoc network environments, this approach can suffer from co-channel interference due to the simultaneous transmission of packets

Efficient Error Concealment for the Whole-frame Loss Based on H.264/AVC

October 15, 2008
Author(s)
Hamid Gharavi, Bo Yan
For low bit-rate video communications, each video frame usually fills the payload of a single network packet. In this situation, the loss of a packet may result in loosing the entire video frame. Currently, most existing error concealment algorithms can

Directional Routing Protocols for Ad Hoc Networks

May 6, 2008
Author(s)
Hamid Gharavi, Bin Hu
This paper presents a directional routing approach for multihop ad-hoc networks, which has been applied to two on-demand routing protocols: namely Dynamic Source Routing (DRS) and Ad Hoc On-Demand Distance Vector Routing (AODV). Both DSR-based and AODV

Spatial Interpolation Algorithm for Error Concealment

April 9, 2008
Author(s)
Hamid Gharavi, Shaoshuai Gao
In this paper, we propose a new spatial interpolation algorithm for Intra-Frame error concealment. The method aims at interpolating areas in the image, which have been affected by packet loss. We have proposed an edge detection technique to aid the

Multi-Channel Mobile Ad-Hoc Links for Multimedia Communications

December 31, 2007
Author(s)
Hamid Gharavi
This paper is mainly concerned with multi-channel transmission of real-time information such as video over multi-hop ad-hoc links. We propose two multi-channel routing protocols. The first is based on single-path routing and aims at suppressing the intra

DSR-Based Directional Routing Protocol for Ad Hoc Networks

November 14, 2007
Author(s)
Bin Hu, Hamid Gharavi
In this paper, a Dynamic Source Routing (DSR)-based directional routing protocol is invoked for wireless ad hoc networks using directional antennas. This is designed to balance the trade-off between co-channel interferences from nodes hops away, and the

3-D Segmentation and Motion Estimation of Range Data for Crash Prevention

June 6, 2007
Author(s)
Hamid Gharavi
In this paper we present a 3-D object segmentation and motion estimation scheme of range video data for crash prevention applications. The segmentation is based on slope values of every point in the scene with which atomic regions are constructed by region

Recursive Motion Estimation of Range Image

April 4, 2007
Author(s)
Hamid Gharavi, Shaoshuai Gao
In this paper, we present an innovative recursive motion estimation technique that can take advantage of the in-depth resolution (range) to perform an accurate estimation of objects that have undergone 3-D translational and rotational movements. This

3-D Motion Estimation Using Range Data

March 1, 2007
Author(s)
Hamid Gharavi, Shaoshuai Gao
Advanced vehicle-based safety and warning systems use laser scanners to measure road geometry (position, curvature), and range to obstacles in order to warn a driver of an impending crash and/or to activate safety devices (air bags, brakes, steering). In

Scanning Advanced Automobile Technology

January 31, 2007
Author(s)
Hamid Gharavi, K V. Prasad, P. Ioannou
The progress of some of the key electrical, electronics, communications, controls and software technologies that enable in-vehicle, vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) functions is presented, in historical, current & futuristic

A Pel-Recursive Motion Estimation Algorithm

January 9, 2007
Author(s)
Hamid Gharavi, H Reza-alikhani
This paper presents a new pel recursive motion estimation algorithm for video coding applications. The derivation of the algorithm is based on Recursive Least-Squares (RLS) estimation that minimizes the mean square prediction error. A comparison with the

Multiple Description Video Coding Over Multiple Path Routing Networks

August 29, 2006
Author(s)
Shaoshuai Gao, Hamid Gharavi
This paper presents a multiple description (MD) video-coding scheme, which uses interlaced high signal to noise ratio (H-SNR) and low signal to noise ratio (L-SNR) coded frames to produce two bit-streams. At the decoder, when both bit-streams are received