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index, respectively. The experimental result demonstrated that the proposed
method is better than signal-to-noise ratio (SNR). Additionally, an artifact distri-
bution of coding schemes at different depth layers within a 3D image was mod-
eled in a single metric [21]. The metric included three steps. Firstly, a set of 2D
image pairs were synthesized at different depth layers using an image based ren-
dering (IBR) scheme. Secondly, pixels that can be discerned to belong to each
depth layer were identified. Finally, the image pairs were masked and the coding
artifact at each depth layer was evaluated using the multi-scale SSIM. Three cod-
ing schemes were studied including two H.264 based pseudo video coding
schemes and JPEG 2000. The experimental results showed a high correlation be-
tween the coding artifacts and their distribution in different depth layers. Gorley et
al. [22] used a new Stereo Band Limited Contrast (SBLC) algorithm to rank
stereoscopic pairs in terms of image quality. SBLC took into account the sensitiv-
ity to contrast and luminance changes in image regions with high spatial fre-
quency. A threshold for evaluating image quality produced by SBLC metric was
found to be closely correlated to subjective measurements. Sazzad et al. [23] as-
sumed that perceived distortion and depth of any stereoscopic images are strongly
dependent on the spatial characteristics in certain image regions, such as edge re-
gions, smooth and texture regions. Therefore, a blockiness index and zero crossing
rates within these regions in an image were then evaluated. They were finally in-
tegrated into a single value using an optimization algorithm according to subjec-
tive quality evaluation results. With respect to a quality database on JPEG coded
stereoscopic images, the model performed quite well over a wide rang of image
contents and distortion levels.
Transport methods of 3DTV were surveyed from early analog systems to most
recent digital technologies in [24]. Potential digital transport architectures for
3DTV include the digital video broadcast (DVB) architecture for broadcast, and
the Internet Protocol (IP) architecture for wired or wireless streaming. Motivated
by a growing impact of IP based media transport technologies, Akar et al. mainly
focused on the ubiquitous Internet by using it as a choice of the network infra-
structure for future 3DTV systems in [24]. To our best knowledge, the quality
evaluation issues for 3D presentations with transmission errors have almost not
addressed so far. However, transmission related factors in IP based architecture
have a non-neglectable impact on the perceived quality of 3D presentations. For
example, different network protocols, such as Datagram Congestion Control Pro-
tocol (DCCP) and Peer-to-Peer Protocols, different transmission control schemes,
e.g. effective congestion control, packet loss protection and concealment, video
rate adaptation, and network/service scalability will definitely affect the quality of
visual experience. The artefacts introduced by the transmission errors (such as
packet loss and jitter) are quite different from the coding artefacts (such as blur-
ring). Therefore, an accurate quality metric should also take into account the char-
acteristics of the transmission artefacts.
Finally, for the video-plus-depth technique, depth image based rendering
(DIBR) is inevitable and the influence of DIBR on the perceptual quality should
also be taken into consideration. Although depth perception can provide more
comfortable experience for end-users, the rendering process of current display
