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In this paper we investigate important issue for real-time video over wireless ad-hoc networks on different layers. Many error control methods for this approach use multiple streams and multipath routing. Thus the new proactive, link-state routing protocol have been developed, where the protocol finds the available route in the network and also it will not cause any interruption in the video traffic between the source and the destination. The open source MPEG-4 is also implemented to get the efficient video quality for the picture.

Connectivity in ad-hoc networks is a fundamental, but to a large extend still unsolved problem. In this paper we consider the connectivity problem when a number of nodes are uniformly distributed within a unit square. We limit our problem to the one-hop and two-hop connectivity. For the one-hop connectivity we find the exact analytically solution. For the two-hop connectivity we find the lower and upper bound for connectivity.

Mobile TV is a new interesting area in the telecommunication industry. The technology for sending live video to mobile clients is characterized by relatively low CPU processing power, low network resources, and low display resolution. In this paper we discuss a solution to all of these problems by using application layer multicasting. This can significantly reduce the needed bitrate and required computing resources for each client. At the same time the received video quality is increased. Several different methods for splitting the video into substreams are discussed. Simulations for the local wireless ad-hoc network are performed. A system for application layer multicasting using layered H.264 is also presented.

In this paper we suggest a promising solution to come over the problems of delivering e-learning to areas with lack or deficiencies in infrastructure for Internet and mobile communication. We present a simple, reasonably priced and efficient communication platform for providing e-learning. This platform is based on wireless ad-hoc networks. We also present a preemptive routing protocol suitable for real-time video communication over wireless ad-hoc networks. Our results show that this routing protocol can significantly improve the quality of the received video. This makes our suggested system not only good to overcome the infrastructure barrier but even capable of delivering a high quality e-learning material.

In this paper we describe the recent development of a low- bandwidth wireless camera sensor network. We propose a simple, yet effective, network architecture which allows multiple cameras to be connected to the network and synchronize their communication schedules. Image compression of greater than 90% is performed at each node running on a local DSP coprocessor, resulting in nodes using 1/8th the energy compared to streaming uncompressed images. We briefly introduce the Fleck wireless node and the DSP/camera sensor, and then outline the network architecture and compression algorithm. The system is able to stream color QVGA images over the network to a base station at up to 2 frames per second.

Sending  video over wireless sensor networks is a challenging task. The encoding and transmission of video is very resource hungry and the sensor nodes have very limited resources in terms of communication bandwidth,memory, computation and  typically 5-10 times. In this paper we will present a practical implementation of a Wyner-Ziv video codec where the reversed asymmetry in complexity between encoder and decoder can be achieved. We will also present our sensor network platform used in this demonstration known as Fleck ^TM-3 as well as two different co-processor daughterboards for image processing. The different daughterboards are then compared in terms of speed and energy consumption.

In this paper we present an approach to provide efficient low-complexity video encoding for wireless sensor networks. We present an method based on removing the most time-consuming task, that is motion estimation, from the encoder. Instead the decoder will perform motion prediction based on the available decoded frame and send the predicted motion vectors to the encoder. We present results based on a modified H.264 implementation. Our results shows that this approach can provide rather good coding efficiency even for relatively high network delays.

This paper proposes an intuitive wireless sensor/actuator based communication network for human animal interaction for a digital zoo. In order to enhance effective observation and control over wild life, we have built a wireless sensor network. 25 video transmitting nodes are installed for animal behavior observation and experimental vibrotactile collars have been designed for effective control in an animal park.

The goal of our research is two-folded. Firstly, to provide an interaction between digital users and animals, and monitor the animal behavior for safety purposes. Secondly, we investigate how animals can be controlled or trained based on vibrotactile stimuli instead of electric stimuli.

We have designed a multimedia sensor network for human animal machine interaction. We have evaluated the effect of human animal machine state communication model in field experiments.

In this chapter we will describe our work to set up a large scale wireless visual sensor network in a Swedish zoo. It is located close to the Arctic Circle making the environment very hard for this type of deployment. The goal is to make the zoo digitally enhanced, leading to a more attractive and interactive zoo. To reach this goal the sensed data will be processed and semantic information will be used to support interaction design, which is a key component to provide a new type of experience for the visitors. In this chapter we will describe our research work related to the various aspects of a digital zoo

In this paper we present our approach to use a combination of radio frequency identification (RFID) and a wireless camera sensor network to identify and track animals at a zoo. We have developed and installed 25 cameras covering the whole zoo. The cameras are totally autonomous and they are configuring themselves in a wireless ad-hoc network. At strategic locations RFID readers are deployed to identify animals in close proximity. The camera network deployed in the zoo is continuous tracking animals in its field of view. By using data fusion from the camera system and the RFID readers we can get semi-continuous tracking of individual animals. The camera network has been running in the zoo for more than one year and about 5 000 hours of video has been captured and recorded. This will give us a very large dataset for offline development and testing of computer vision algorithms for animal detection and tracking.