This work is focusing on the definition of a procedure for the qualification of coding schemes for video surveillance
applications. It consists in developing and benchmarking tools that learn from the expertise of police and security
department. This expertise is intended to be modeled thanks to a campaign of subjective measurement allowing to
analyze the way they are using in performing the security tasks like face or license plate recognition, event detection and
so on. The results of the previous test are used will be used to tune and to construct a hybrid metric based on basic
artifacts detection due to compression and transmission.
Compressed video is the digital raw material provided by video-surveillance systems and used for archiving and
indexing purposes. Multimedia standards have therefore a direct impact on such systems. If MPEG-2 used to be the
coding standard, MPEG-4 (part 2) has now replaced it in most installations, and MPEG-4 AVC/H.264 solutions are now
being released. Finely analysing the complex and rich MPEG-4 streams is a challenging issue addressed in that paper.
The system we designed is based on five modules: low-resolution decoder, motion estimation generator, object motion
filtering, low-resolution object segmentation, and cooperative decision. Our contributions refer to as the statistical
analysis of the spatial distribution of the motion vectors, the computation of DCT-based confidence maps, the automatic
motion activity detection in the compressed file and a rough indexation by dedicated descriptors. The robustness and
accuracy of the system are evaluated on a large corpus (hundreds of hours of in-and outdoor videos with pedestrians and
vehicles). The objective benchmarking of the performances is achieved with respect to five metrics allowing to estimate
the error part due to each module and for different implementations. This evaluation establishes that our system analyses
up to 200 frames (720x288) per second (2.66 GHz CPU).
The EU FP6 WCAM (Wireless Cameras and Audio-Visual Seamless Networking) project aims to study, develop and validate a wireless, seamless and secured end-to-end networked audio-visual system for video surveillance and multimedia distribution applications. This paper describes the video transmission aspects of the project, with contributions in the areas of H.264 video delivery over wireless LANs.
The planned demonstrations under WCAM include transmission of H.264 coded material over 802.11b/g networks with TCP/IP and UDP/IP being employed as the transport and network layers over unicast and multicast links. UDP based unicast and multicast transmissions pose the problem of packet erasures while TCP based transmission is associated with long delays and the need for a large jitter buffer. This paper presents measurement data that have been collected at the trial site along with analysis of the data, including characterisation of the channel conditions as well as recommendations on the optimal operating parameters for each of the above transmission scenarios (e.g. jitter buffer sizes, packet error rates, etc.). Recommendations for error resilient coding algorithms and packetisation strategies are made in order to moderate the effect of the observed packet erasures on the quality of the transmitted video. Advanced error concealment methods for masking the effects of packet erasures at the receiver/decoder are also described.
In this paper, we present an integrated system for smart encoding in video surveillance. This system, developed within the European IST WCAM project, aims at defining an optimized JPEG 2000 codestream organization directly based on the semantic content of the video surveillance analysis module. The proposed system produces a fully compliant Motion JPEG 2000 stream that contains regions of interest (typically mobile objects) data in a separate layer than regions of less interest (e.g. static background). First the system performs a real-time unsupervised segmentation of mobiles in each frame of the video. The smart encoding module uses these regions of interest maps in order to construct a Motion JPEG 2000 codestream that allows an optimized rendering of the video surveillance stream in low bandwidth wireless applications, allocating more quality to mobiles than for the background. Our integrated system improves the coding representation of the video content without data overhead. It can also be used in applications requiring selective scrambling of regions of interest as well as for any other application dealing with regions of interest.
In this paper, we present an integrated system for video surveillance developed within the European IST WCAM project, using only standard multimedia and networking tools. The advantages of such a system, while allowing cost reduction and interoperability, is to benefit from the fast technological evolution of the video encoding and distribution tools.
In this paper, we present the current status of the JPWL standardization work item. JPWL is an extension of the JPEG 2000 baseline specification in order to enable the efficient transmission of JPEG 2000 codestream over an error-prone network. In particular, JPWL supports a set of tools and methods for error protection and correction such as Forward Error Correcting (FEC) codes, Unequal Error Protection (UEP), and data partitioning and interleaving. We then evaluate the performance of the JPWL Error Protection Block (EPB) tool. We consider two configurations of EPB: to protect the Main and Tile-part headers, or to protect the whole codestream using UEP. Experimental results show a significant quality improvement when using EPB compared to baseline JPEG 2000.