Publications by Touradj Ebrahimi

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Personal computing and communication devices such as computers, personal digital assistants (PDAs), and mobile phones are moving to their next generation in which the end user will be able to access a multitude of information with a single device either locally or through a network. One likely trend in future personal computing and personal communication is that there will not be a single but several equivalent devices available to users allowing access to information in various forms. Each user, depending

This paper describes a video surveillance system which is composed of three key components, smart cameras, a server, and clients, connected through IP-networks in wired or wireless configurations. The system has been designed so as to protect the privacy of people under surveillance. Smart cameras are based on JPEG 2000 compression where an analysis module allows for events detection and regions of interest identification. The resulting regions of interest can then be encoded with better quality and scrambl

Light field representation promises to overcome the limitations of stereoscopic representation by allowing for a more seamless transition between multiple points of views, thus giving a more faithful representation of 3D scenes. However, in order to take f ...

Assessing emotional states of users evoked during their multimedia consumption has received a great deal of attention with recent advances in multimedia content distribution technologies and increasing interest in personalized content delivery. Physiologic ...

Among various subjective quality evaluation methodologies, paired comparison has the advantage of improved simplicity of the subjects’ evaluation task due to simplified rating scales and direct comparison of two stimuli. Thus, it may lead to more reliable ...

Point cloud imaging has emerged as an efficient and popular solution to represent immersive visual information. However, the large volume of data generated in the acquisition process reveals the need of efficient compression solutions in order to store and transmit such contents. Several standardization committees are in the process of finalizing efficient compression schemes to cope with the large volume of information that point clouds require. At the same time, recent efforts on learning-based compressio

The JPEG 2000 Suite provides a comprehensive overview of the baseline JPEG 2000 standard and its extensions. The first part of the book sets out the core coding system, additions to the standard and reference software. The second part discusses the successful deployment of JPEG 2000 in application domains such as video surveillance, digital cinema, digital television, medical imaging, defence imaging, security, geographic imaging and remote sensing, digital culture imaging and 3D graphics. The book also pre

Joint Photographic Experts Group (JPEG) XS is a new International Standard from the JPEG Committee (formally known as ISO/International Electrotechnical Commission (IEC) JTC1/SC29/WG1). It defines an interoperable, visually lossless low-latency lightweight ...

This paper describes the MPEG-4 standard, as defined in ISO/IEC 14496-2. The MPEG-4 visual standard is developed to provide users a new level of interaction with visual contents. It provides technologies to view, access and manipulate objects rather than pixels, with great error robustness at a large range of bit-rates. Application areas range from digital television, streaming video, to mobile multimedia and games. The MPEG-4 natural video standard consists of a collection of tools that support these appli

As 3D image and video content has gained significant popularity, subjective 3D quality assessment has become an important issue for the creation, processing, and distribution of high quality 3D content. Reliable subjective quality assessment of 3D content ...

The task of extracting a semantic video object is split into two subproblems, namely, object segmentation and region segmentation. Object segmentation relies on a priori assumptions, whereas region segmentation is data-driven and can be solved in an automatic manner. These two subproblems are not mutually independent, and they can benefit from interactions with each other. In this paper, a framework for such interaction is formulated. This representation scheme based on region segmentation and semantic segm

In order to permit a brain computer efficient communication, it is important to dispose of an efficient algorithm to decode the brain electrical activity. We will focus our attention on an algorithm based on microstates segmentation of the brain electrical activity. First of all, we are going to use electroencephalogram measurements (EEG, 10/20 international system) to collect the electrical activity of the brain. Each sixteen electrodes of the EEG will sample the data at the same rate, forming a matrix of

Deepfakes - synthetic videos generated by machine learning models - are becoming increasingly sophisticated. While they have several positive use cases, their potential for harm is also high. Deepfake production involves input from multiple engineers, maki ...

A brain-computer interface (BCI) is a communication system, that implements the principle of "think and make it happen without any physical effort". This means a BCI allows a user to act on his environment only by using his thoughts, without using peripheral nerves and muscles. Nearly all BCIs contain as a core part a machine learning algorithm that is used to discriminate different brain activities. In the present work we use a bayesian framework for machine learning, the evidence framework, to develop a v

The use of point clouds as an imaging modality has been rapidly growing, motivating research on compression methods to enable efficient transmission and storage for many applications. While compression standards relying on conven- tional techniques such as ...

Tagging in online social networks is very popular these days, as it facilitates search and retrieval of diverse resources available online. However, noisy and spam annotations often make it difficult to perform an efficient search. Users may make mistakes ...

In this paper, we propose an original framework for an intuitive tuning of parameters in image and video segmentation algorithms. The proposed framework is very flexible and generic and does not depend on a specific segmentation algorithm, a particular evaluation metric, or a specific optimization approach, which are the three main components of its block diagram. This framework requires a manual segmentation input provided by a human operator as he/she would have performed intuitively. This input allows th

This paper presents a foveated coding method using audio-visual focus of attention and its evaluation through extensive subjective experiments on both standard definition and high definition sequences. Regarding a sound-emitting region as the location draw ...

Media assets shared via social media can rapidly spread, even if they do not present a true representation of reality. The assets might have been manipulated with photo editing software, artificially created using deep learning techniques or used out of co ...

Guaranteeing interoperability between devices and applications is the core role of standards organizations. Since its first JPEG standard in 1992, the Joint Photographic Experts Group (JPEG) has published several image coding standards that have been succe ...

Touradj Ebrahimi

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Universal multimedia access from wired and wireless systems

Video surveillance using JPEG 2000

Rendering-dependent compression and quality evaluation for light field contents

Affect Recognition Based on Physiological Changes During the Watching of Music Video

A new analysis method for paired comparison and its application to 3D quality assessment

Towards neural network approaches for point cloud compression

Ongoing standardization efforts

JPEG XS-A New Standard for Visually Lossless Low-Latency Lightweight Image Coding

MPEG-4 natural video coding - An overview

Paired comparison-based subjective quality assessment of stereoscopic images

Interaction between High-Level and Low-Level Image Analysis for Semantic Video Object Extraction

Brain states analysis for direct brain-computer communication

A multimodal measurement of the impact of deepfakes on the ethical reasoning and affective reactions of students

Application of the Evidence Framework to Brain-Computer Interfaces

Evaluating the effect of sparse convolutions on point cloud compression

Spam Fighting in Social Tagging Systems

Intuitive Strategy for Parameter Setting in Video Segmentation

Subjective quality evaluation of foveated video coding using audio-visual focus of attention

JPEG Fake Media: a Provenance-based Sustainable Approach to Secure and Trustworthy Media Annotation

JPEG Pleno: Providing representation interoperability for holographic applications and devices