Disocclusion Holes Research Articles

Stereoscopic view synthesis with progressive structure reconstruction and scene constraints.

Depth image-based rendering (DIBR) is an important technology in the process of 2D-to-3D conversion. It uses texture images and related depth maps to render virtual views. While there are still some challenging problems in the current DIBR systems, such as disocclusion occurrences. Inpainting methods based on deep learning have recently shown significant improvements and generated plausible images. However, most of these methods may not deal well with the disocclusion holes in the synthesized views, because on the one hand they only treat this issue as generative inpainting after 3D warping, rather than following the full DIBR processing procedures. While on the other hand the distributions of holes on the virtual views are always around the transition regions of foreground and background, which makes them more difficult to distinguish without special constraints. Motivated by these observations, this paper proposes a novel learning-based method for stereoscopic view synthesis, in which the disocclusion regions are restored by a progressive structure reconstruction strategy instead of direct texture inpainting. Additionally, some special cues in the synthesized scenes are further exploited as constraints for the network to alleviate hallucinated structure mixtures among different layers. Extensive empirical evaluations and comparisons validate the strengths of the proposed approach and demonstrate that the model is more suitable for stereoscopic synthesis in the 2D-to-3D conversion applications.

Real-World Virtual Reality With Head-Motion Parallax.

Most of the real-world virtual reality (VR) content available today is captured and rendered from a fixed vantage point. The visual-vestibular conflict arising from the lack of head-motion parallax degrades the feeling of presence in the virtual environment and has been shown to induce nausea and visual discomfort. We present an end-to-end framework for VR with head-motion parallax for real-world scenes. To capture both horizontally and vertically separated perspectives, we use a camera rig with two vertically stacked rings of outward-facing cameras. The data from the rig are processed offline and stored into a compact intermediate representation, which is used to render novel views for a head-mounted display, in accordance with the viewer's head movements. We compare two promising intermediate representations-Stacked OmniStereo and Layered Depth Panoramas-and evaluate them in terms of objective image quality metrics and the occurrence of disocclusion holes in synthesized novel views.

Layered approach for improving the quality of free-viewpoint depth-image-based rendering images

In free-viewpoint rendering systems, one of the most challenging goals is the creation of virtual views based on available color texture (RGB) and depth data. Conventional depth-image-based rendering (DIBR) approaches have assumed that the virtual camera can only be displaced horizontally, thus leading to fairly simple disocclusion artifacts. However, in free-viewpoint DIBR, the virtual camera can be positioned in an arbitrary way and the respective disocclusion artifacts can exhibit complicated anisotropic appearances. Consequently, conventional approaches for compensating disocclusion holes usually fail in such arbitrary camera motion. We present a disocclusion compensation technique based on texture inpainting. We propose a layered representation of both the color and depth images in local foreground, background, and undefined segments (a trimap). This representation allows for employing an efficient alpha-matting approach for reconstructing the underlying opacity layer followed by a background compensation and layered rendering. The performance of the proposed method is evaluated with respect to the state-of-the-art through objective and subjective tests. The achieved results, especially for large camera displacements, outperform the state-of-the-art. Those results assess the effectiveness of the proposed method and highlight the need for new quality metrics able to address the impairments of this type of content.

Proxy‐guided Image‐based Rendering for Mobile Devices

AbstractVR headsets and hand‐held devices are not powerful enough to render complex scenes in real‐time. A server can take on the rendering task, but network latency prohibits a good user experience. We present a new image‐based rendering (IBR) architecture for masking the latency. It runs in real‐time even on very weak mobile devices, supports modern game engine graphics, and maintains high visual quality even for large view displacements. We propose a novel server‐side dual‐view representation that leverages an optimally‐placed extra view and depth peeling to provide the client with coverage for filling disocclusion holes. This representation is directly rendered in a novel wide‐angle projection with favorable directional parameterization. A new client‐side IBR algorithm uses a pre‐transmitted level‐of‐detail proxy with an encaging simplification and depth‐carving to maintain highly complex geometric detail. We demonstrate our approach with typical VR / mobile gaming applications running on mobile hardware. Our technique compares favorably to competing approaches according to perceptual and numerical comparisons.