Publications by Touradj Ebrahimi

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Olfaction-enhanced multimedia experience is becoming vital for strengthening the sensation of reality and the quality of user experience. One approach to investigate olfactory perception is to analyze the alterations in brain activity during stimulation with different odors. In this article, the changes in the electroencephalogram (EEG) when perceiving hedonically-different odors are studied. Results of within and across-subject analysis are presented. We show that EEG-based odor classification using brain

This paper presents a high-capacity method to embed information into the geometry of a 3D polygonal mesh. The method extends a previously reported work, to which several improvements have been brought. By construction, the new embedding algorithm is robust against rotation, scaling and translation attacks. Analysis of the proposed method on different meshes showed that its embedding capacity compares to that of previous high-capacity works. Furthermore, the new technique introduces only negligible amount of

Scalable video coding is emerging as an efficient alternative to simulcast encoding to distribute the same video content si- multaneously to many users having different terminals and network conditions. In order to select the best combination of video scal ...

Content-based video retrieval has become a very active research area in the last decade due to the increasing number of video shared on social networks such as YouTube and Daily-Motion. While most of the content-based video retrieval approaches employ visu ...

In this paper, we introduce a scheme for coding video surveillance camera networks. It is based on multiview and Distributed Video Coding (DVC). DVC is known for its low complexity encoders. This makes it very interesting for a wide range of applications, in particular video surveillance. More specifically, we introduce a new fusion technique between temporal side information and homography-based side information that improves the rate-distortion performance of the DVC compression. Finally, we introduce a n

Archival of audio-visual databases has become an important discipline in multimedia. Various defects are typically present in such archives. Among those, one can mention recording related defects such as interference between audio and video signals, optical related artifacts, recording and play out artifacts such as horizontal lines, and dropouts, as well as those due to digitization such as diagonal lines. An automatic or semi-automatic detection to identify such defects is useful, especially for large dat

In person re-identification, individuals must be correctly identified in images that come from different cameras or are captured at different points in time. In the open-set case, the above needs be achieved for people who have not been previously recognis ...

Broadcasting high dynamic range (HDR) video has been demonstrated as largely preferred when compared to standard dynamic range (SDR), mainly due to its capability of representing more details in dark and bright regions. Additionally, progress over the last ...

Distributed Video Coding (DVC) is a new paradigm for video compression based on the information theoretical results of Slepian and Wolf (SW) and Wyner and Ziv (WZ). DVC entails low complexity encoders as well as separate encoding of correlated video source ...

Non-fungible tokens (NFTs) are becoming very popular in a large number of applications ranging from copyright protection to monetization of both physical and digital assets. It is however a fact that NFTs suffer from a large number of security issues that ...

Despite the huge success of deep convolutional neural networks in face recognition (FR) tasks, current methods lack explainability for their predictions because of their ``black-box'' nature. In recent years, studies have been carried out to give an interp ...

Point cloud is a promising imaging modality for the representation of 3D media. The vast volume of data associated with it requires efficient compression solutions, with lossy algorithms leading to larger bit-rate savings at the expense of visual impairmen ...

In this paper, we describe our approach and discuss evaluation results for the MediaEval 2012 Visual Privacy task. The goal of the task is to obscure faces of people visible in provided surveillance clips to preserve their personal privacy. We also additio ...

In this paper, we introduce novel schemes for scalable Distributed Video Coding (DVC), dealing with temporal, spatial and quality scalabilities. More specifically, conventional coding is used to obtain a base layer. DVC is then applied to generate enhancem ...

In this paper an objective metric to measure the perceptual quality of watermarked 3D meshes is presented. The metric relies on a multiscale measurement of the roughness of 3D meshes before and after the watermark insertion. The validity of the proposed metric has been tested against a number of different 3D watermarking algorithms, showing an excellent match with the subjective evaluation of the quality derived from pshycovisual experiments.

Deep convolutional neural networks have shown remarkable results on face recognition (FR). Despite their significant progress, the performance of current face recognition techniques is often assessed in benchmarks under not always realistic conditions. The ...

In this work, a performance evaluation of AVC Intra and JPEG2000 in terms of rate-distortion performance is conducted. A rich set of test sequences with different spatial resolutions is used in this evaluation. Furthermore, the comparison is made with both the Main and High profiles of AVC Intra. For high spatial resolution sequences, our results show that JPEG2000 is very competitive with AVC High Profile Intra and outperforms the Main Profile. For Intermediate and low spatial resolution sequences JPEG2000

A novel approach to shadow detection is presented in this paper. The method is based on the use of invariant color models to identify and to classify shadows in digital images. The procedure is divided into two levels: first, shadow candidate regions are extracted; then, by using the invariant color features, shadow candidate pixels are classified as self shadow points or as cast shadow points. The use of invariant color features allows a low complexity of the classification stage. Experimental results show

Omnidirectional image and video, also known as 360 image and 360 video, are gaining in popularity with the recent growth in availability of cameras and displays that can cope with such type of content. As omnidirectional visual content represents a larger set of information about the scene, it typically requires a much larger volume of information. Efficient compression of such content is therefore important. In this paper, we review the state of the art in compression of omnidirectional visual content, and

With the rapid growth of digital photography, sharing of photos with friends and family has become very popular. When people share their photos, they usually organize them in albums according to events or places. To tell the story of some important events in one's life, it is desirable to have an efficient summarization tool which can help people to get a quick overview of an album containing huge number of photos. In this paper, we analyze an approach for photo album summarization through a novel social ga

Touradj Ebrahimi

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EEG Correlates of Pleasant and Unpleasant Odor Perception

Data Hiding on 3D Polygonal Meshes

Objective quality metrics for video scalability

3D Object Duplicate Detection for Video Retrieval

Fusion-based Multiview Distributed Video Coding

Automatic defect detection in video archives - Application to Montreux Jazz Festival Digital Archives

Open-Set Person Re-Identification through Error Resilient Recurring Gallery Building

Quality assessment of an HDR dual-layer backward-compatible codec compared to uncompromised SDR and HDR solutions

Iterative Multiview Side Information for Enhanced Reconstruction in Distributed Video Coding

Effective know-your-customer method for secure and trustworthy non-fungible tokens in media assets

Discriminative Deep Feature Visualization for Explainable Face Recognition

Benchmarking of objective quality metrics for point cloud compression

MediaEval 2012 Visual Privacy Task: Applying Transform-domain Scrambling to Automatically Detected Faces

Codec-Independent Scalable Distributed Video Coding

A Multi-Scale Roughness Metric for 3D Watermarking Quality Assessment

A Novel Framework for Assessment of Deep Face Recognition Systems in Realistic Conditions

On Comparing JPEG 2000 and Intraframe AVC

Shadow identification and classification using invariant color models

JPEG backward compatible coding of omnidirectional images

Social game Epitome versus automatic visual analysis