2 research outputs found
A Fast Free-viewpoint Video Synthesis Algorithm for Sports Scenes
In this paper, we report on a parallel freeviewpoint video synthesis
algorithm that can efficiently reconstruct a high-quality 3D scene
representation of sports scenes. The proposed method focuses on a scene that is
captured by multiple synchronized cameras featuring wide-baselines. The
following strategies are introduced to accelerate the production of a
free-viewpoint video taking the improvement of visual quality into account: (1)
a sparse point cloud is reconstructed using a volumetric visual hull approach,
and an exact 3D ROI is found for each object using an efficient connected
components labeling algorithm. Next, the reconstruction of a dense point cloud
is accelerated by implementing visual hull only in the ROIs; (2) an accurate
polyhedral surface mesh is built by estimating the exact intersections between
grid cells and the visual hull; (3) the appearance of the reconstructed
presentation is reproduced in a view-dependent manner that respectively renders
the non-occluded and occluded region with the nearest camera and its
neighboring cameras. The production for volleyball and judo sequences
demonstrates the effectiveness of our method in terms of both execution time
and visual quality.Comment: 7 pages, 11 figure
A Robust Billboard-based Free-viewpoint Video Synthesizing Algorithm for Sports Scenes
We present a billboard-based free-viewpoint video synthesizing algorithm for
sports scenes that can robustly reconstruct and render a high-fidelity
billboard model for each object, including an occluded one, in each camera. Its
contributions are (1) applicable to a challenging shooting condition where a
high precision 3D model cannot be built because a small number of cameras
featuring wide-baseline are equipped; (2) capable of reproducing appearances of
occlusions, that is one of the most significant issues for billboard-based
approaches due to the ineffective detection of overlaps. To achieve
contributions above, the proposed method does not attempt to find a
high-quality 3D model but utilizes a raw 3D model that is obtained directly
from space carving. Although the model is insufficiently accurate for producing
an impressive visual effect, precise objects segmentation and occlusions
detection can be performed by back-projecting it onto each camera plane. The
billboard model of each object in each camera is rendered according to whether
it is occluded or not, and its location in the virtual stadium is determined
considering the location of its 3D model. We synthesized free-viewpoint videos
of two soccer sequences recorded by five cameras with the proposed and
state-of-art methods to demonstrate its performance.Comment: 10 pages, 13 figure