Patrick Ndjiki-Nya

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Perceptual quality metrics are widely deployed in image and video processing systems. These metrics aim to emulate the integral mechanisms of the human visual system (HVS) to correlate well with visual perception of quality. One integral property of the HVS is, however, often neglected: visual attention (VA) [1]. The essential mechanisms associated with VA(More)
A depth image-based rendering (DIBR) approach with advanced inpainting methods is presented. The DIBR algorithm can be used in 3-D video applications to synthesize a number of different perspectives of the same scene, e.g., from a multiview-video-plus-depth (MVD) representation. This MVD format consists of video and depth sequences for a limited number of(More)
A new video coding approach based on texture analysis and synthesis is presented. The underlying assumption of our approach is that the textures in a video scene can be labeled subjectively relevant or irrelevant. Relevant textures are defined as containing subjectively meaningful details, while irrelevant textures can be seen as image content with less(More)
3DTV technology has brought out new challenges such as the question of synthesized views evaluation. Synthesized views are generated through a depth image-based rendering (DIBR) process. This process induces new types of artifacts whose impact on visual quality has to be identified considering various contexts of use. While visual quality assessment has(More)
In free viewpoint television or 3D video, depth image based rendering (DIBR) is used to generate virtual views based on a textured image and its associated depth information. In doing so, image regions which are occluded in the original view may become visible in the virtual image. One of the main challenges in DIBR is to extrapolate known textures into the(More)
A new approach to video coding is presented, where video scenes are classified into textures with subjectively relevant and irrelevant details. We apply this idea to improve video coding by using a texture analyzer and a texture synthesizer. The analyzer identifies the texture regions with no important subjective details and generates coarse masks as well(More)
An effective texture synthesis method is presented that is inspired by the work of Kwatra et al. [1]. Their algorithm is non-parametric and patch-based. Blending between overlapping patches is optimized using graph cut techniques. We generalize the initial approach [ 1 ] to achieve a new synthesis algorithm that yields improved results for a much larger(More)
Depth image-based rendering (DIBR) techniques allow for a wide variety of 3-D applications, including synthesizing additional virtual views in a multiview-video-plus-depth (MVD) representation. The MVD format consists of scene texture and depth information for a limited number of original views of the same scene. One of the main obstacles in the DIBR(More)
Depth-image-based rendering (DIBR) is used to generate additional views of a real-world scene from images or videos and associated per-pixel depth information. An inherent problem of the view synthesis concept is the fact that image information which is occluded in the original view may become visible in the “virtual” image. The resulting(More)
A video coding approach that uses texture analysis at the encoder and synthesis at the decoder is presented. It is characterized by scaling of texture reconstruction accuracy at the decoder according to perceptual relevance to the viewer. A closed-loop concept is proposed for a fully automated approach that can be integrated into any video codec. Besides(More)