The interest in objective quality assessment have significantly increased over the past decades. Several objective quality metrics have been proposed and made publicly available, moreover, several subjective quality assessment databases are distributed in order to evaluate and compare the metrics. However, several question arises: are the objective metrics behaviours constant across databases, contents and distortions? how significantly the subjective scores might fluctuate on different displays (i.e. CRT or LCD)? which objective quality metric might best evaluate a given distortion? In this article, we analyse the behaviour of four objective quality metrics (including PSNR) tested on three image databases. We demonstrate that the performances of the quality metrics can strongly fluctuate depending on the database used for testing. We also show the consistency of all metrics for two distinct displays.

Motion-blur is still an important issue on liquid crystal displays (LCD). In the last years, efforts have been done in the characterization and the measurement of this artifact. These methods permit to picture the blurred profile of a moving edge, according to the scrolling speed and to the gray-to-gray transition considered. However, other aspects should be taken in account in order to understand the way LCD motion-blur is perceived. In the last years, a couple of works have adressed the problem of LCD motion-blur perception, but only few speeds and transitions have been tested. In this paper, we have explored motion-blur perception over 20 gray-to-gray transitions and several scrolling speeds. Moreover, we have used three different displays, to explore the influence of the luminance range as well as the blur shape on the motion-blur perception. A blur matching experiment has been set up to obtain the relation between objective measurements and perception. In this experiment, observers must adjust a stationary test blur (simulated from measurements) until it matches their perception of the blur occuring on a moving edge. Result shows that the adjusted perceived blur is always lower than the objective measured blur. This effect is greater for low contrast edges than for high contrast edges. This could be related to the motion sharpening phenomenon.

Abstract— The primary goal of this study was to find a measurement method for motion blur which is easy to carry out and gives results that can be reproduced from one lab to another. This method should be able to also take into account methods for reduction of motion blur such as backlight flashing. Two methods have been compared. The first method uses a high‐speed camera that permits us to directly picture the blurred‐edge profile. The second one exploits the mathematical analysis of the motion‐blur formation to construct the blurred‐edge profile from the temporal step response. Measurement results and method proposals are given and discussed.

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Abstract-Consumer interest in 3D television (3DTV) is growing steadily, but current available 3D displays still need additional eye-wear and suffer from the limitation of a single stereo view pair. So it can be assumed that auto-stereoscopic multiview displays are the next step in 3D-at-home entertainment, since these displays can utilize the Multiview Video plus Depth (MVD) format to synthesize numerous viewing angles from only a small set of given input views. This motivates efficient MVD compression as an important keystone for commercial success of 3DTV. In this paper we concentrate on the compression of depth information in an MVD scenario. There have been several publications suggesting depth down-and upsampling to increase coding efficiency. We follow this path, using our recently introduced Edge Weighted Optimization Concept (EWOC) for depth upscaling. EWOC uses edge information from the video frame in the upscaling process and allows the use of sparse, non-uniformly distributed depth values. We exploit this fact to expand the depth down-/upsampling idea with an adaptive lowpass filter, reducing high energy parts in the original depth map prior to subsampling and compression. Objective results show the viability of our approach for depth map compression with up-to-date High-Efficiency Video Coding (HEVC). For the same Y-PSNR in synthesized views we achieve up to 18.5% bit rate decrease compared to full-scale depth and around 10% compared to competing depth down-/upsampling solutions. These results were confirmed by a subjective quality assessment, showing a statistical significant preference for 87.5% of the test cases.

International audienceThe 3D video quality is of highest importance for the adoption of a new technology from a user's point of view. In this paper we evaluated the impact of coding artefacts on stereoscopic 3D video quality by making use of several existing full reference 2D objective metrics. We analyzed the performance of objective metrics by comparing to the results of subjective experiment. The results show that pixel based Visual Information Fidelity metrics fits subjective data the best. The 2D stereoscopic video quality seems to have dominant impact on the coding artefacts impaired stereoscopic videos

New display technologies enable the usage of 3D-visualization in a medical context. Even though user performance seems to be enhanced with respect to 2D thanks to the addition of recreated depth cues, human factors, and more particularly visual comfort and visual fatigue can still be a bridle to the widespread use of these systems. This study aimed at evaluating and comparing two dierent 3D visualization systems (a market stereoscopic display, and a state-of-the-art multi-view display) in terms of quality of experience (QoE), in the context of interactive medical visualization. An adapted methodology was designed in order to subjectively evaluate the experience of users. 14 medical doctors and 15 medical students took part in the experiment. After solving dierent tasks using the 3D reconstruction of a phantom object, they were asked to judge their quality of the experience, according to specic features. They were also asked to give their opinion about the inuence of 3D-systems on their work conditions. Results suggest that medical doctors are opened to 3D-visualization techniques and are condent concerning their benecial inuence on their work. However, visual comfort and visual fatigue are still an issue of 3D-displays. Results obtained with the multi-view display suggest that the use of continuous horizontal parallax might be the future response to these current limitations.