Enriching the viewing experience of TV programs using virtual content insertion

19.1 Introduction Over the years, the rapid technical advances in multimedia compression and broadband network delivery have led to a huge amount of multimedia content created and distributed. With the advanced digital TV technologies and easy-to-use electrical devices, for example, digital cameras, digital camcorders, and smart phones, creating multimedia contents will no longer be peculiar to the professionals and power users. In addition, with dramatically boosted social media services, such as YouTube, AudioBoo, Flickr, Facebook, Plurk, and so on, people can easily create, share, and watch tremendous amounts of multimedia contents in their daily lives. Therefore, people can access rich multimedia content through various media easily. In order to attract more viewers, the TV programs should be refined to be more interesting and useful according to different requirements of various types of TV services (e.g., advertising, education, or entertainment, etc.). Nowadays, users can shape their vivid personal lives via the uniqueness, creativity, and interest of their own multimedia contents and thereby share experiences and knowledge with each other. This phenomenon of personal branding has become a popular culture trend and the market now pays high attention to the latent yet amazing economic benefits of advertising that accompanied with the trend. Besides advertising, digital TV service is also opening up opportunities for interactive learning services to reach mass audiences. It is popular to record the lecture as a digital video for efficient distribution through the Internet. However, general lectures take at least 1 h and will produce a large video file. Consequently, it becomes di?cult for learners to browse the lecture content e?ciently. In addition, while watching the traditional lecture video, students usually feel bored because it lacks interaction with the teacher or classmates. Therefore, additional interactive content should be incorporated in the self-paced learning environment to help students learn efficiently.