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Suche nach „[A.] [Raake]“ hat 12 Publikationen gefunden
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    DigitalAngewandte Informatik

    Beitrag (Sammelband oder Tagungsband)

    P. Lebreton, A. Raake, Marcus Barkowsky

    Studying user agreement on aesthetic appeal ratings and its relation with technical knowledge

    2016 Eighth International Conference on Quality of Multimedia Experience (QoMEX)

    2016

    DOI: 10.1109/QoMEX.2016.7498934

    Abstract anzeigen

    In this paper, a crowdsourcing experiment was conducted involving different panels of participants. The aim of this study is to evaluate how the preference of one image over another one is related with the knowledge of the participant in photography. In previous work the two discriminant evaluation concepts \textquoteright were found to distinguish group participants with different degrees of knowledge in photography. Each of these groups provided different means of aesthetic appeal ratings when asked to rate on an absolute category scale. The present paper extends previous work by studying preference ratings on a set of image pairs as a function of technical knowledge and more specifically adding a focus on the variance of rating and agreement between participants. The conducted study was composed of two different steps where the participants had to first report their preference of one image over another (paired comparison), and an evaluation of the technical background of the participant using a specific set of images. Based on preference-rating patterns groups of participants were identified. These groups were formed by clustering the participants who saw and shared the same preference rating on images in one group, and the participants with low agreement with other participants in another group. A per-group analysis showed that a high agreement between participants could be observed when participants have technical knowledge. This indicates that higher consistency between participants can be reached when expert users are being recruited, and therefore participants should be carefully selected in image aesthetic appeal evaluation to ensure stable results.

    DigitalAngewandte Informatik

    Beitrag (Sammelband oder Tagungsband)

    P. Lebreton, A. Raake, Marcus Barkowsky

    Evaluation of aesthetic appeal with regard of user\textquoterights knowledge

    Proceedings of SPIE Conference Human Vision and Electronic Imaging 2016 (HVEI 2016)

    2016

    DigitalAngewandte Informatik

    Beitrag (Sammelband oder Tagungsband)

    P. Lebreton, A. Raake, Marcus Barkowsky, P. Le Callet

    Open perceptual binocular and monocular descriptors for stereoscopic 3D images and video characterization

    2015 Seventh International Workshop on Quality of Multimedia Experience (QoMEX)

    2015

    Abstract anzeigen

    This paper presents a toolbox for monocular and binocular depth estimation and an analysis of performance for some of these. At first, the definition of an appropriate depth indicator (DI) metric for 3D contents is discussed. To this aim, different algorithms from the literature for the characterization of 3D videos are compared. Results show that the simple 7.5 percentile of the disparity map values can already be an indicator, even though it may fail to address several perceptual aspects. In the latter cases, more advanced algorithms presented in this paper may be a better approach. In a second step, monocular depth indicators are described and analyzed in this paper. All code and tools enabling binocular and monocular depth estimation such as depth-map estimation, depth map characterization and monocular depth cue indicator computation is provided open-source. This will enable researchers to further characterize their 3D and 2D contents, for example before running a subjective experiment, or to automatically pre-screen 3D content that is to be presented to a larger number of viewers.

    DigitalAngewandte Informatik

    Beitrag (Sammelband oder Tagungsband)

    P. Lebreton, A. Raake, Marcus Barkowsky, P. Le Callet

    Evaluating complex scales through subjective ranking

    2014 Sixth International Workshop on Quality of Multimedia Experience (QoMEX)

    2014

    Abstract anzeigen

    In this paper, a subjective assessment methodology based on ranking, reordering and image categorization is proposed. It is designed to facilitate the evaluation of complex features such as monocular depth cues in natural images. These features can be particularly challenging to explain to test participants, and the proposed methodology is designed to provide to the test participants more insights and examples about the scale under evaluation. The performances of the method are compared to the absolute category rating methodology, and the advantages of each part of the test design are studied to verify the added value of the different steps of the evaluation procedure. Results show that the method is promising and can improve stability between subjective test participant results.

    DigitalAngewandte Informatik

    Beitrag (Sammelband oder Tagungsband)

    P. Lebreton, Marcus Barkowsky, A. Raake, P. Le Callet

    Chapter 20: 3D Video

    Quality of Experience: Advanced Concepts, Applications and Methods

    2014

    ISBN: 978-3-319-02680-0

    DigitalAngewandte Informatik

    Beitrag (Sammelband oder Tagungsband)

    P. Lebreton, A. Raake, Marcus Barkowsky, P. Le Callet

    Measuring perceived depth in natural images and study of its relation with monocular and binocular depth cues

    Proceedings of SPIE Vol. 9011: IS&T/SPIE Electronic Imaging Stereoscopic Displays and Applications XXV , San Francisco, CA, USA

    2014

    Abstract anzeigen

    The perception of depth in images and video sequences is based on different depth cues. Studies have considered depth perception threshold as a function of viewing distance (Cutting & Vishton,1995), the combination of different monocular depth cues and their quantitative relation with binocular depth cues and their different possible type of interactions (Landy,1995). But these studies only consider artificial stimuli and none of them attempts to provide a quantitative contribution of monocular and binocular depth cues compared to each other in the specific context of natural images. This study targets this particular application case. The evaluation of the strength of different depth cues compared to each other using a carefully designed image database to cover as much as possible different combinations of monocular (linear perspective, texture gradient, relative size and defocus blur) and binocular depth cues. The 200 images were evaluated in two distinct subjective experiments to evaluate separately perceived depth and different monocular depth cues. The methodology and the description of the definition of the different scales will be detailed. The image database is also released for the scientific community.

    DigitalAngewandte Informatik

    Beitrag (Sammelband oder Tagungsband)

    Marcus Barkowsky, K. Brunnström, T. Ebrahimi, L. Karam, P. Lebreton, P. Le Callet, A. Perkis, A. Raake, M. Subedar, K. Wang, L. Xing, J. You

    Subjective and Objective Visual Quality Assessment in the Context of Stereoscopic 3D-TV

    3D-TV System with Depth-Image-Based Rendering

    2013

    ISBN: 978-1-4419-9963-4

    DOI: 10.1007/978-1-4419-9964-1_14

    DigitalAngewandte Informatik

    Beitrag (Sammelband oder Tagungsband)

    P. Lebreton, A. Raake, Marcus Barkowsky, P. Le Callet

    Perceptual preference of S3D over 2D for HDTV in dependence of video quality and depth

    2013 IEEE 11th IVMSP Workshop

    2013

    Abstract anzeigen

    3D video quality of experience (QoE) is a multidimensional problem and many factors contribute to the global experience by the user. Due to this multidimensionality, this paper evaluates the integral 3D video QoE and relates it with image quality and depth. Subjective tests have been conducted using paired comparison to evaluate 3D QoE and the preference of 3D over 2D with different combinations of coding conditions. Depth scores were available from previous work and were used to check their relation with 3DQoE; the difference between 2D and 3D QoE is found to be a function of the picture quality, and the desired preference of 3D presentation over 2D can be reached when pictorial quality is high enough (VQM score lower than 0.24). A factor ranging from 0.08 to 0.76 with a mean of 0.71 between pictorial quality and preference of 3D was also found.

    DigitalAngewandte Informatik

    Beitrag (Sammelband oder Tagungsband)

    P. Lebreton, A. Raake, Marcus Barkowsky, P. Le Callet

    Perceptual depth indicator for S-3D content based on binocular and monocular cues

    2012 Conference Record of the Forty Sixth Asilomar Conference on Signals, Systems and Computers (ASILOMAR)

    2012

    Abstract anzeigen

    This article describes a general depth indicator for stereoscopic 3D video sequences. This indicator targets the characterization of the depth in 3D video sequences based on both monocular and binocular depth cues. Evaluating monocular depth cues is no easy task. Due to this high complexity, only a subset of the monocular depth cues are currently considered since it is believed that they play a major impact in depth perception. The proposed algorithm will consider the following different depth cues: binocular depth, linear perspective, blur from defocus, motion parallax and texture gradient. It will be detailed how all these all metrics have been designed. The second main contribution is the definition of a specific application scope of each metrics. This is motivated by the need to take into account the reliability of each individual metrics during the pooling. Therefore, it will be considered in the paper to identify the cases where each individual metric may fail and integrate these aspects in the general combination of the depth cues.

    DigitalAngewandte Informatik

    Beitrag (Sammelband oder Tagungsband)

    P. Lebreton, A. Raake, U. Wustenhagen, T. Buchholz, Marcus Barkowsky, P. Le Callet

    A subjective and objective evaluation of a realistic 3D IPTV transmission chain

    Proceedings of the 19th International Packet Video Workshop (PV) 2012, München

    2012

    Abstract anzeigen

    In 3D transmissions, often a large perceptual quality gain can be achieved by slightly increasing the bitrate. However, at a certain bitrate, a saturation effect is noted and further increasing the bitrate does not lead to significant improvements of Quality of Experience (QoE). This bitrate will be called quality saturation bitrate. The purpose of this paper is to investigate a subjective and objective method to determine the quality saturation bitrate. An evaluation is presented which uses a wide spread of content types and a realistic transmission chain that includes a hardware encoder and commercial Set-Top-Boxes. A subjective assessment for various bitrates is performed using the SAMVIQ methodology and the results are also compared to objective measurements with VQM and VQUAD.

    DigitalAngewandte Informatik

    Zeitschriftenartikel

    P. Lebreton, A. Raake, Marcus Barkowsky, P. Le Callet

    Evaluating Depth Perception of 3D Stereoscopic Videos

    IEEE Journal of Selected Topics in Signal Processing, vol. 6, no. 6, pp. 710-720

    2012

    Abstract anzeigen

    3D video quality of experience (QoE) is a multidimensional problem; many factors contribute to the global rating like image quality, depth perception and visual discomfort. Due to this multidimensionality, it is proposed in this paper, that as a complement to assessing the quality degradation due to coding or transmission, the appropriateness of the non-distorted signal should be addressed. One important factor here is the depth information provided by the source sequences. From an application-perspective, the depth-characteristics of source content are of relevance for pre-validating whether the content is suitable for 3D video services. In addition, assessing the interplay between binocular and monocular depth features and depth perception are relevant topics for 3D video perception research. To achieve the evaluation of the suitability of 3D content, this paper describes both a subjective experiment and a new objective indicator to evaluate depth as one of the added values of 3D video.

    DigitalAngewandte Informatik

    Beitrag (Sammelband oder Tagungsband)

    P. Lebreton, A. Raake, Marcus Barkowsky, P. Le Callet

    A Subjective Evaluation of 3D IPTV Broadcasting Implementations Considering Coding and Transmission Degradation

    IEEE International Symposium on Multimedia (ISM)

    2011

    Abstract anzeigen

    This paper describes the results of a subjective test to assess current technology used for 3DTV broadcasting. As a first aspect, the performance of the currently deployed coding schemes was compared to state of the art algorithms. Our results show that down sampling and packing 3D stereoscopic videos according to the so called Side-By-Side format gives the highest perceived quality for a given bit rate. The second aspect of the study was to investigate how common 2D error concealment algorithms perform in case of 3D, and how their 3D-related performance compares with the 2D case. The results provide information on whether binocular suppression or binocular rivalries play the most important role for 3D video quality under transmission error. The results indicate that binocular rivalries and related visual discomfort are the dominant factors. Another aspect of the paper is a comparison of the test results with results from different labs to evaluate the repeatability of a subjective experiment in the 3D case, and to compare the employed test methodologies. Here, the study shows the variation between observers when they are rating visual discomfort and illustrates the difficulty to evaluate this new dimension.