Publications de Lutz Goldmann | EPFL Graph Search

Paired comparison-based subjective quality assessment of stereoscopic images

Touradj Ebrahimi, Jong Seok Lee, Lutz Goldmann

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 ...

Springer Verlag2013

Geotag Propagation in Social Networks Based on User Trust Model

Touradj Ebrahimi, Ivan Ivanov, Péter Vajda, Jong Seok Lee, Lutz Goldmann

In the past few years sharing photos within social networks has become very popular. In order to make these huge collections easier to explore, images are usually tagged with representative keywords such as persons, events, objects, and locations. In order ...

Springer2012

Towards a Descriptive Depth Index for 3D Content: Measuring Perspective Depth Cues

Touradj Ebrahimi, Lutz Goldmann

2012

Robust Duplicate Detection of 2D and 3D Objects

Touradj Ebrahimi, Ivan Ivanov, Péter Vajda, Jong Seok Lee, Lutz Goldmann

In this paper, the authors analyze their graph-based approach for 2D and 3D object duplicate detection in still images. A graph model is used to represent the 3D spatial information of the object based on the features extracted from training images to avoi ...

IGI Global2012

Towards High Efficiency Video Coding: Subjective Evaluation of Potential Coding Technologies

Touradj Ebrahimi, Francesca De Simone, Jong Seok Lee, Lutz Goldmann

This paper describes the details and the results of the subjective quality evaluation performed at EPFL, as a contribution to the effort of the joint collaborative team on video coding (JCT-VC) for the definition of the high efficiency video coding (HEVC) ...

Elsevier2011

Omnidirectional object duplicate detection

Touradj Ebrahimi, Ivan Ivanov, Péter Vajda, Lutz Goldmann

With the technological evolution of digital acquisition and content analysis, millions of images and video sequences are captured every day and used in a large variety of applications. As keyword-based indexing is very time consuming and inefficient due to ...

Ieee Service Center, 445 Hoes Lane, Po Box 1331, Piscataway, Nj 08855-1331 Usa2011

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

Touradj Ebrahimi, Jong Seok Lee, Lutz Goldmann

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 ...

2011

Towards reliable and reproducible 3D video quality assessment

Touradj Ebrahimi, Lutz Goldmann

The success of 3D video, as one of the emerging multimedia formats, will largely depend on the improved quality of experience that it provides to viewers when compared to conventional 2D video. Therefore reliable methods for 3D video quality assessment are ...

Spie-Int Soc Optical Engineering, Po Box 10, Bellingham, Wa 98227-0010 Usa2011

Let Epitome summarize your photo collection!

Touradj Ebrahimi, Ivan Ivanov, Péter Vajda, Lutz Goldmann

2011

Motion Parallax Based Restitution of 3D Images on Legacy Consumer Mobile Devices

Touradj Ebrahimi, Jong Seok Lee, Lutz Goldmann, Martin Rerabek

While 3D display technologies are already widely available for cinema and home or corporate use, only a few portable devices currently feature 3D display capabilities. Moreover, the large majority of 3D display solutions rely on binocular perception. In th ...

Ieee Service Center, 445 Hoes Lane, Po Box 1331, Piscataway, Nj 08855-1331 Usa2011

A Comprehensive Database and Subjective Evaluation Methodology for Quality of Experience in Stereoscopic Video

Touradj Ebrahimi, Francesca De Simone, Lutz Goldmann

2010

Impact of Acquisition Distortion on the Quality of Stereoscopic Images

Touradj Ebrahimi, Francesca De Simone, Lutz Goldmann

2010

Object-based Tag Propagation for Semi-automatic Annotation of Images

Touradj Ebrahimi, Ivan Ivanov, Péter Vajda, Jong Seok Lee, Lutz Goldmann

Over the last few years, social network systems have greatly increased users’ involvement in online content creation and annotation. Since such systems usually need to deal with a large amount of multimedia data, it becomes desirable to realize an interact ...

2010

3D Object Duplicate Detection for Video Retrieval

Touradj Ebrahimi, Ivan Ivanov, Péter Vajda, Jong Seok Lee, Lutz Goldmann

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 ...

2010

Social Game Epitome versus Automatic Visual Analysis

Touradj Ebrahimi, Ivan Ivanov, Péter Vajda, Lutz Goldmann

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 ...

2010

Impact of video transcoding artifacts on the subjective quality

Touradj Ebrahimi, Mauro Lattuada, Frédéric Dufaux, Francesca De Simone, Lutz Goldmann

Video transcoding is an important step to enable interoperability between different networks, terminals, applications, and services for video communication. This paper studies the influence of typical video transcoding artifacts due to frame rate reduction ...

2010

On the Limits of Perceptually Optimized JPEG

Touradj Ebrahimi, Denis Filimonov, Francesca De Simone, Lutz Goldmann

The study presented in this paper aims at quantifying the empirical limits of JPEG optimization, when the compressed stream is standard compliant and only the quantization tables are optimized. Image-dependent quantization tables, which minimize the bitrat ...

2010

Propagation of geotags based on object duplicate detection

Touradj Ebrahimi, Ivan Ivanov, Péter Vajda, Jong Seok Lee, Lutz Goldmann

In this paper, we consider the use of object duplicate detection for the propagation of geotags from a small set of images with location names (IPTC) to a large set of non-tagged images. The motivation behind this idea is that images of individual location ...

Spie-Int Soc Optical Engineering, Po Box 10, Bellingham, Wa 98227-0010 Usa2010

Robust Duplicate Detection of 2D and 3D Objects

Touradj Ebrahimi, Ivan Ivanov, Péter Vajda, Jong Seok Lee, Lutz Goldmann

In this paper, we analyze our graph-based approach for 2D and 3D object duplicate detection in still images. A graph model is used to represent the 3D spatial information of the object based on the features extracted from training images so that an explici ...

2010

Temporal Synchronization in Stereoscopic Video: Influence on Quality of Experience and Automatic Asynchrony Detection

Touradj Ebrahimi, Jong Seok Lee, Lutz Goldmann

In this paper, we analyze the inﬂuence of temporal asyn- chrony on the subjective quality of stereoscopic video. Based on our recently created 3D video database, different levels of asynchrony were simulated and a comprehensive subjective test was conducte ...

Ieee Service Center, 445 Hoes Lane, Po Box 1331, Piscataway, Nj 08855-1331 Usa2010