Real-time Depth-Image-Based Rendering on GPU
Zengzeng Sun
SRC-Xian DMC Lab/SSG, Samsung Electronics
Xi’an, China
zengzeng.sun@samsung.com
Cheolkon Jung
School of Electronic Engineering, Xidian University
Xi’an 710071, China
zhengzk@xidian.edu.cn
Abstract—In this paper, we propose real-time depth-image-
based rendering (DIBR) on GPU for 1280×720 resolution. We
utilize depth adaptive preprocessing and super-resolution to
achieve high-quality DIBR. Moreover, we employ GPU-based
parallel computing to achieve real-time DIBR. Experimental
results demonstrate that the proposed method achieves
superior performance in comparison with the existing methods
with respect to rendering quality and computing time.
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Keywords- Depth-image-based rendering (DIBR), GPU, hole
filling, parallel computing, real-time.
I. INTRODUCTION
Stereoscopic 3D (S3D) videos are considered as a new
media which provides a realistic and immersive experience
to viewers [1]. They are captured by stereo imaging systems
imitating the human visual system (HVS), and played in S3D
displays such as 3DTV which provides viewers with 3D
effects [2]. Because they are recorded by 3D stereoscopic
cameras like 2D situations, there are some critical issues
such as synchronizing the stereoscopic cameras [3], storing
and transmission of a huge amount of data [4], etc. In
practice, future S3D displays provide viewers with the
services of navigating through the scenes to choose an
appropriate viewpoint depending on their positions for
reality and immersive, which is known as free-viewpoint
television (FTV) [5]. It is of more practical use to use S3D
videos using stereoscopic cameras. The existing 2D videos
should be converted into 3D ones to play on S3D displays.
Thus, recent studies have focused on virtual view synthesis
which generates various intermediate views using limited
number of camera images. Depth-image-based rendering
(DIBR) [6] is a well-known technique of virtual view
synthesis which generates novel views from a 2D reference
image and its corresponding depth image. A coding standard
for the video-plus-depth representation, known as MPEG-C
part 3 [7], is issued by MPEG due to the compression-
efficiency for transmission and compatibility with the
existing 2D broadcasting system. DIBR is also a core
technology in advanced three dimensional television system
(ATTEST 3DTV System) [8] whose goals include a 2D
compatible coding and transmission scheme for S3D videos
using MPEG-2/4/7 and a flexible and commercially feasible
3DTV system for broadcast environments. For the virtual
view synthesis, the 3D warping should be performed to map
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This work was supported by the National Natural Science Foundation of
China (No. 61271298) and the International S&T Cooperation Program of
China (No. 2014DFG12780).
the pixels in the 2D reference image into desired virtual view
using explicit geometric information, depth maps, and
camera viewpoint parameters [9]. However, the 3D warping
generates obvious holes in the synthesized virtual view
mostly caused by the reason that occluded areas in the
reference image become visible in the synthesized virtual
view. The hole problem is an inherent problem in DIBR
because it has a great influence on the visual perceptual
quality of the generated S3D videos.
Various techniques have been proposed for hole-filling
[10]-[18]. They are classified into two main groups:
interpolation based hole-filling [10]-[14] and inpainting-
based hole-filling [15]-[17]. Recently, Solh et al. have
proposed a novel hole-filling approach in DIBR referred to
as hierarchal hole-filling (HHF) that fills in the holes using a
pyramid-like structure [18]. HHF yields a better rendering
quality than the other approaches, but suffers from blurred
results in the hole area around the object because the
upsampling from lower resolution produces blurred effects.
It is noteworthy that Zhang et al. [11] first introduce depth
map preprocessing into DIBR framework (see Fig. 1) which
is composed of three major components because a depth map
with horizontal sharp edges would result in big holes after
3D warping. They reduce the size of big holes before 3D
warping by smoothing the edges of the depth sharp transition,
which can make the subsequent hole-filling much more
easier. However, depth map preprocessing may bring about
the problems of geometric distortions and losses in depth
cues [19]. Thus, several approaches have been proposed to
reduce the artifacts of depth map preprocessing, but still
suffer from the annoying phenomena and remarkably
increasing the computational complexity. To implement
image processing algorithms in fast speed or real-time, the
parallelization based on graphics processing unit (GPU) have
recently become an active topic in the community [20], [21].
Real-time processing is required in the practical applications,
and the resultant quality of implementation should be
ensured under the real-time constraint as well.
Fig. 1 DIBR with depth map preprocessing, redrawn from [11].
2015 International Conference on Cyber-Enabled Distributed Computing and Knowledge Discovery
978-1-4673-9200-6/15 $31.00 © 2015 IEEE
DOI 10.1109/CyberC.2015.97
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