Video databases and applications were traditionally only to be available to users having high-end devices connected to special analog video networks or highspeed local-area networks. This is no longer the case due to technical progress being made in several areas: The steady increase in computational power being built into standard computers has removed the need for high-end computers to be able to enjoy video applications. High network bandwidths are also becoming available in public networks through cable modems and digital subscriber lines  enabling customer access to digital video applications through public networks. The most important change that has occurred, however, is the new video compression methods and streaming video players, such as the Microsoft Windows Media player  and the RealNetworks player , which makes it possible for most Internet users to access digital video services using ordinary modems.
These changes have created new challenges and opportunities for video database application developers. Traditional video database applications were digital library types of applications used to archive, index/catalog, and retrieve elements of a video production . Today, the majority of video database application users are ordinary users on the Internet. These users bring a new set of expectations and requirements to the developers of video database applications. The most important ones are related to (video) quality, availability, and interactivity. This chapter will mostly address the two latter issues and is based on experiences made by the authors while developing two different interactive video database applications: HotStreams™ - a system for delivering and managing personalized video content - and TEMA (Telephony Enabled Multimedia Applications) - a platform for developing Internet-based multimedia applications for Next Generation Networks (NGN). This chapter is organized as follows:
Section 2 discusses how the World Wide Web and its set of technologies and standards have changed the environment for digital video applications.
Section 3 introduces the interactive video database applications being developed at Siemens Corporate Research.
Section 4 discusses tools and technologies for adding interactivity to video database applications.
The Internet is a heterogeneous network that offers a wide range of bandwidths and that can be accessed by a diverse set of devices having different capabilities, such as screen size, color depth, processing capabilities, etc. Section 5 discusses how this diversity affects video database applications and describes some tools and technologies to handle differences in network and device capabilities.
Many Internet sites allow their users to create their interest profile. This way, end-users have come to appreciate localized and personalized content and services. Section 6 shows some technologies that can be used to generate localized and personalized video content.
The Internet has also become a medium for people to share information and experiences through the use of electronic mail, instant messaging, chat rooms, etc. Section 7 explores tools and technologies that enable video information sharing among end-users.