Distributed Video Coding (DVC) is a new paradigm in video coding, based on the Slepian-Wolf and Wyner-Ziv theorems. DVC offers a number of potential advantages: flexible partitioning of the complexity between the encoder and decoder, robustness to channel errors due to intrinsic joint source-channel coding, codec independent scalability, and multi-view coding without communications between the cameras. In this paper, we evaluate the performance of DVC in an error-prone wireless communication environment. We also present a hybrid spatial
and temporal error concealment approach for DVC. Finally, we perform a comparison with a state-of-the-art AVC/H.264 video coding scheme in the presence of transmission errors.
In this paper, a novel video scrambling scheme is introduced for Distributed Video Coding. The goal is to conceal
video information to preserve privacy in several applications such as video surveillance and anonymous video
communications. This is achieved by performing a transform domain scrambling on both Key and Wyner-Ziv
frames. More specifically, the sign of the scrambled transform coefficient is inverted at the encoder side. The
scrambling pattern is defined by a secret key and the latter is required at the decoder for descrambling. The
scheme is proven to provide a good level of security in addition to a flexible scrambling level (i.e the amount of
distortion introduced). Finally, it is shown that the original DVC scheme and the one with scrambling have a
similar rate distortion performance. In other words, the DVC compression efficiency is not negatively impacted
by the introduction of the scrambling.
In this paper, we report a study evaluating rate-distortion performance between JPEG 2000, AVC/H.264 High 4:4:4 Intra
and HD Photo. A set of ten high definition color images with different spatial resolutions has been used. Both the PSNR
and the perceptual MSSIM index were considered as distortion metrics. Results show that, for the material used to carry
out the experiments, the overall performance, in terms of compression efficiency, are quite comparable for the three
coding approaches, within an average range of ±10% in bitrate variations, and outperforming the conventional JPEG.
We consider dense networks of surveillance cameras capturing overlapped images of the same scene from different
viewing directions, such a scenario being referred to as multi-view. Data compression is paramount in such a system due
to the large amount of captured data. In this paper, we propose a Multi-view Distributed Video Coding approach. It
allows for low complexity / low power consumption at the encoder side, and the exploitation of inter-view correlation
without communications among the cameras. We introduce a combination of temporal intra-view side information and
homography inter-view side information. Simulation results show both the improvement of the side information, as well
as a significant gain in terms of coding efficiency.
In this work, a performance evaluation of AVC Intra and JPEG2000 in terms of rate-distortion performance is
conducted. A rich set of test sequences with different spatial resolutions is used in this evaluation. Furthermore, the
comparison is made with both the Main and High profiles of AVC Intra.
For high spatial resolution sequences, our results show that JPEG2000 is very competitive with AVC High Profile Intra
and outperforms the Main Profile. For Intermediate and low spatial resolution sequences JPEG2000 is outperformed by
both Profiles of AVC Intra.
In this paper, we address the problem privacy in video surveillance. We propose an efficient solution based on transformdomain
scrambling of regions of interest in a video sequence. More specifically, the sign of selected transform
coefficients is flipped during encoding. We address more specifically the case of Motion JPEG 2000. Simulation results
show that the technique can be successfully applied to conceal information in regions of interest in the scene while
providing with a good level of security. Furthermore, the scrambling is flexible and allows adjusting the amount of
distortion introduced. This is achieved with a small impact on coding performance and negligible computational
complexity increase. In the proposed video surveillance system, heterogeneous clients can remotely access the system
through the Internet or 2G/3G mobile phone network. Thanks to the inherently scalable Motion JPEG 2000 codestream,
the server is able to adapt the resolution and bandwidth of the delivered video depending on the usage environment of the