In recent years, transmission of video over the Internet has become an important application. As wireless networks are becoming increasingly popular, it is expected that video will be an important application over wireless networks as well. Unlike wired networks, wireless networks have high data loss rates. Streaming video in the presence of high data loss can be a challenge because it results in errors in the video.<p>Video applications produce large amounts of data that need to be compressed for efficient storage and transmission. Video encoders compress data into dependent frames and independent frames. During transmission, the compressed video may lose some data. Depending on where the packet loss occurs in the video, the error can propagate for a long time. If the error occurs on a reference frame at the beginning of the video, all the frames that depend on the reference frame will not be decoded successfully. <p>This thesis presents the concept of mixed streaming, which reduces the impact of video propagation errors in error prone networks. Mixed streaming delivers a video file using two levels of reliability; reliable and unreliable. This allows sensitive parts of the video to be delivered reliably while less sensitive areas of the video are transmitted unreliably. Experiments are conducted that study the behavior of mixed streaming over error prone wireless networks. Results show that mixed streaming makes it possible to reduce the impact of errors by making sure that errors on reference frames are corrected. Correcting errors on reference frames limits the time for which errors can propagate, thereby improving the video quality. Results also show that the delay cost associated with the mixed streaming approach is reasonable for fairly high packet loss rates.

No description available.

The Internet is increasingly used to deliver multimedia service. To accommodate heterogeneous receivers and to adapt to congestion, it has been proposed to use adaptive rate control techniques to adjust the video traffic characteristics according to the available Internet resources, such as layered video multicast. A problem of layered video multicast is unable to provide fair bandwidth sharing between competing video sessions. In this thesis, we will introduce a better solution to achieve inter-session fairness for layered video multicast.

We implement the ¡§Internet Video Conference System¡¨ based on ITU-T H.323 multimedia communication protocols standard in paper. This part, we discuss the H.323 protocols how to work on the Internet and analysis the network structure on the video conference system. Development of the system will consider network structure restrict, user habits and system integrate problem. We are not development the point-point communication, but also development multipoint communication by the multicast concept. To solve the distance and capacity problem on video conference, we research the ¡§Zone Switching¡¨ and ¡§Multi-MCU¡¨ structure this paper. We analysis the performance of the video conference system by the new structure, it includes ¡§switching structure of the different Zone¡¨ and ¡§switching structure of the same Zone¡¨. Finally, we analysis the performance and work on the Internet by the new structure.

The objective of my research is to create a visualization of a place based on personal experiences. My research addresses this issue through a case study: the visualization of a women’s political prison located in Punta de Rieles, Uruguay, during the Uruguayan dictatorship (1973-85). In June of 2002, I went to Uruguay and interviewed nine female former political prisoners. I asked them to tell me stories about what happened to them during their time in prison. My research aims at relating their experience of prison through a visualization of their stories. The challenge addressed by my research is the creation of a virtual reconstruction that can communicate the experience of prison through the integration of narrative, light modeling and sound. The proposed visualization is a video installation based on these women’s personal experiences of the solitary confinement cell (calabozo).

This dissertation examines how games have been construed legally and publicly and compares the nature of games to the de facto legal criteria: in order for games to receive free speech protection, games must inform and communicate. In Chapter I, I review the literature surrounding the effects of violent video games. This literature review serves as a foundation for the rhetorical nature of the legal controversy since the controversy has no clear-cut answer to the effects of video games. Instead of a clear "Yes"€ or "€œNo"€ answer, game effects researchers can only posit "Maybe"€ and "No"€ findings. Game antagonists employed long-shot and shoddy research to argue their case that violent games produce violent people. The next two chapters lay a foundation for justifying why games have become increasingly controversial to date. In Chapter II, I outline a history of games and argue that games became communicative in the early 1990s. As a response to graphically communicative games and congressional bullying, the video game industry created a self regulatory rating board which should have quelled the public controversy. It did not. In Chapter III, I argue that Columbine changed the face of the game industry in the eyes of the public, as a matter of public morality. Before 1999, the public viewed games in a positive light, embodying one of America'€™s pastimes and helping the disabled with their motor skills. After the events at Columbine, the public saw the video game industry as an unruly and rogue force. In Chapter IV, I explain the legal hurtles the game industry faces in becoming protected speech. While video games have become communicative and informative, they likely will not receive free speech protection because of the public scapegoating of the industry during the last two and a half decades. I conclude by discussing the latest Grand Theft Auto "€œHot Coffee"€ controversy and how game developers remain gun-shy about the free speech issue.

With the rapid growth of multimedia information, video coding standards have become crucial when transmitting large amount of video data. Motion estimation promises to be the key to high performance in video coding by removing the temporal redundancy of video data for storage and transmission. Video transcoding also becomes a significant scheme applied in different bandwidth transform. Due to their fundamentality, research works on motion estimation and video transcoding have been conducted extensively. In this thesis, an overview of video compression technique is presented with emphasis on motion estimation. Then, a survey of most representative motion estimation search algorithms and the proposed motion estimation algorithms are introduced. The evaluation and analysis of these algorithms based on a number of experiments on several famous test video sequences is presented. In addition, an efficient video transcoding via visual attention model with Lagrange optimization to minimum rate-distortion cost is proposed. Finally, an investigation of the future trend of video coding is discussed. Through the proposed algorithms of motion estimation, the computational complexity can be significantly reduced despite the fact that the objective quality of motion compensated images is slightly degraded. Moreover, through the proposed video transcoding method, the bit rate can be reduced to fit the requirement of bandwidth.

Thesis (Ph. D.)--University of California, San Diego, 2001. / Vita. For flute (doubling piccolo), oboe, E♭ clarinet (doubling B♭ clarinet), trumpet, trombone, piano, organ (doubling synthesizer), 2 violins, viola, violoncello, and double bass, with 3 conductors and video projection. Includes performance instructions and frames from the video printed preceding the score.

Thesis (Ph.D.)--University of Texas at Arlington, 2008.

Thesis (Ph.D )--University of Texas at Arlington, 2009.