University of Houston
Department of Computer Science


In partial fulfillment of the Requirements for the Degree of
Master of Science


Saurabh Mohan
will defend his thesis

Characterizing the Bandwidth Requirements of Compressed Videos

Abstract
VOD broadcasting protocols provide an efficient mechanism for distributing videos that are likely to be watched by many customers. Unfortunately most VOD broadcasting protocols assume that videos have a fixed bandwidth corresponding to a fixed consumption rate. This assumption is false as most of the digitally encoded videos are compressed and compressed videos have a variable bit rate (VBR) . Thus any VOD service will have to distribute VBR video data to its customers.

In order to better understand the bandwidth characteristics of these videos, we analyzed and measured the bandwidth requirements of four full-length MPEG-2 encoded videos. These videos were selected as representatives of the different video genres that could be offered by a VOD system. These genres include action videos, romantic comedies, cartoons and sport events. We then used the bandwidth characteristics of MPEG-2 videos to analyze the performance of the Fast broadcasting and the Mayan temple broadcasting protocols. Our results clearly indicate that the bandwidth characteristics for different video genres vary over a broad range of values. They also show that Mayan temple protocol, which has been designed for transmission of VBR videos, outperforms FB protocol, which assumes a constant bit rate. One can safely conclude from our data that VOD protocols that are specifically developed for the transmission of compressed videos would better utilize the channel bandwidth than protocols developed for broadcasting of videos with constant bit rate.

Date: Friday, March 23, 2001
Time: 11:00 AM
Place: 550-PGH

Faculty, students, and the general public are invited.
Thesis Advisor: Dr. J.F. Paris