CS525 S2006 Semeseter Projects
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rainbow animatio

CS525 Spring 2006 Final Review

Final exam will be in class exam Monday 4:30pm 5/15 in EN109.  An alternate day for those who would like to take earlier will be 5/12 Friday 4:30pm EN177.

We will cover the following topics in the final.

CS525 Spring 2000 Final Exam

CS525 Spring 98 Final Exam

There are five problems. You have 2 hours. Your grade will be based on the best three answers. You are encouraged to answer all five problems. Some problems are more tedious than others. Use your time wisely. When the problems is not clear to you, make your own assumptions and show all your work. Write down your name and phone number to reach you.
Name:  Phone:
Problem 1. Copier Memory Design.
Assume a fixed data rate, 4 Mbps instead of 1.5Mbps is generated by a 100 minute NTSC movie stored in the copier memory. We plan to use a RAID Level 0 system with 8 ultra wide SCSI-2 disks. Each disk has 4 heads. Each head has 80 Mbps data transfer rate. The ultra wide SCSI channel has 40 MBps transfer rate.
  1. How many ultra wide SCSI channels are needed in this RAID 0 system to avoid that the SCSI channels (buses) becomes the bottleneck?
  2. What is the reason of using RAID0 instead of RAID3? Hint: the original movie is in a CD changer storage system.
  3. How many bytes of the disk space are needed to store the movie?
  4. How many phases can each head produce?
  5. Assume that the movie is striped over the whole RAID0 system. How long is a phase?
  6. What is the size of start-stop buffer, in terms of bytes?
  7. Can the start-stop buffer handle fast rewind?
Problem 2. VoD Storage Server. Answer the following questions based on the paper presented by Dr. Du in JSAC.
  1. What is the maximum number of concurrent HDTV video streams that they achieved using the block size of 128, frame size of 16KB, single RAID3 in their VoD prototype?
  2. Why the application level  striping system performs better than the logical volume striping system?
  3. For a video retrieval process, what memory management features are needed to guarantee its performance to meet the real-time requirement?
  4. What are the possible limiting factors in a VoD storage system?
Problem 3. Media Synchronization based on the survey paper by Blakowski and STeinmetz.  In your homework #3 "Multimedia authoring project using Authorware", you are asked to provide an animation of a car driving to EAS parking lot. At the beginning of the animation you would like to play some light music. As the car approaching the first traffic light, you would like to stop the music and then play the voice direction "turn left on the traffic light" just before the car reaches the traffic light. Assume that the car animation are divided into several portions. The first portion terminates when the car reaches the traffic light. Assume here we would like achieve a tight synchronization between the end of this voice direction and the end of the car animation. We would like the voice direction to stop 1 second before the end of animation. Let animate1 represent the first portion of the car animation. Let voice1 be the voice direction. and Let music1 be the light music.
  1. Specify the synchronization of those three media objects using the interval-based method.  Follow the slide show example in page 20 of the paper. Try to use  the operations in Figure 24.
  2. Specify the above synchronization requirement using virtual time axes specification method.
  3. Specify the above synchronization requirement  using the time Petri net.

Problem 4. Rate Matching.
Given the audio/video teleconference example I gave.  The audio is recording at 8000 samples per second and 1 byte per sample.  It is being transferred at 500 samples per packet. The video is recording at 24 frames per seconds. At the receiving site, we use the logical time system to synchronize the audio and video playback. Let us assume that the video is playing back slowly at 1.1 times of the original recording speed, and assume the video interrupts are happening at a fix constant interval. With audio served as a master device,

  1. When will the first rate matching event occur?
  2. How often it occurs?
  3. Is the video frame being skipped or paused?
Problem 5. Synchronized Multimedia Integration Language (SMIL).
The new proposed SMIL  standard is based on the basic hierarchical specification method and provides the following tags and attributes for specifying the synchronization among multimedia objects: Using these SMIL tags and attributes to specify the multimedia presentation that satisfies the synchronization requirement of problem 3. Assume that we know the duration of animate1 (src="animate1.avi") is 20 seconds. The duration of voice1 (src="voice1.wav") is 3 seconds.  The duration of music1 (src="music1.mid") is 22 seconds.