CS 414 Multimedia Systems Design Lecture 41 Final

CS 414 – Multimedia Systems Design Lecture 41 – Final Exam Review Session Klara Nahrstedt Spring 2012 CS 414 - Spring 2012

Project Competition Results n Finalists for the competition ¨ Group 1, Group 2, Group 3, Group 4 n Competition results: ¨ 1 st Place: Group 1 – Robert Schiele, David Jordan, Eric Johnson, Andrew Kryczka ¨ 2 nd Place: Group 3 – Aviral Jain, Aadher Jain, Abhishek Sharma ¨ 3 rd Place: Group 4 – Kevin Schilling, Robert Samblanet, Timothy Park, Raphael Hsieh n Congratulation to all finalists and winners!

Administrative (1) n Homework 2 is posted ¨ Deadline n May 2, Wednesday midnight 11: 59 pm Peer Evaluations – due Friday, May 4, midnight ¨ Peer Evaluation Form and Explanation - available on the class website ¨ Submit your Peer Evaluation to klara@illinois. edu ¨ Note: if you do not submit your peer evaluations, you get 0 for self-evaluation and 100% for your group mates. n ¼ Unit projects – due Friday, May 4 midnight (if you need more time, arrange deadline with instructor) CS 414 - Spring 2012

Administrative (2) n Return of leased equipment before the semester is over!!! n Return web cameras by May 11 to Barb Leisner in 2312 SC , 9 -4 pm. n Note: if a webcam has problems, let Barb Leisner know (no charge, but we need to know in order to recycle faulty webcams) CS 414 - Spring 2012

Administrative (3) - Final Exam n May 11, 1: 30 -4: 30 pm in two rooms ¨ ROOMS 1105 SC and 1109 SC ¨ Students with last names A-K in room 1105 SC ¨ Students with last names L-W in room 1109 SC CS 414 - Spring 2012

Administrative (4) n Final Grades for the class will be posted by May 12 in Banner and Compass systems n Re-grading requests for final exam ¨ You can come and see your exam in my office - arrange meeting via email to klara@illinois. edu or n via assistant Lynette Lubben llubben@illinois. edu n Meetings in May possible or in Fall 2012. n CS 414 - Spring 2012

Administrative (5) - Final Exams Closed book and closed notes exam n You are allowed calculator n You are allowed a A 4 -size sheet with class material information (both sides) n CS 414 - Spring 2012

Administrative (6) – Final Exam n Additional office hours ¨ Wednesday, May 9, 9 -10 am in 3104 SC ¨ Thursday, May 10, 9 -10 am in 3104 SC CS 414 - Spring 2012

Final Exam Topics n Reading List – Lectures ¨ Slides from Lectures 14 – 40 (follow the slides and use the book as a suplement material Reading List – Multimedia Systems Book n MPs – questions from MPs n CS 414 - Spring 2012

Networks n Chapter 2 – Qo. S ¨ All topics except Qo. S routing n Chapter 5 ¨ 5. 1 Service and Network requirements n Chapter 6 ¨ 6. 1 requirements and constraints ¨ (No IPv 4/IPv 6 – did not cover) ¨ (No UDP/TCP nor RSVP/Diff. Serv) – did not cover) ¨ 6. 5. 2 RTP/RTCP CS 414 - Spring 2012

Networks n Chapter 7 ¨ 7. 4 Session Management ¨ 7. 5. 1 SDP/SAP/SIP/RTSP CS 414 - Spring 2012

Media Servers n Chapter 4 ¨ 4. 1 Architecture ¨ 4. 2 Storage Devices (No RAID – did not cover) ¨ 4. 3 Disk Controller ¨ 4. 4 Storage Management 4. 4. 1 disk management n 4. 4. 3 multimedia disk scheduling n 4. 4. 4 admission control n CS 414 - Spring 2012

Buffer Management n Chapter 3 ¨ 3. 3. 1 -3. 3. 3 buffer management techniques, buffer management for client-server systems ¨ Conditions of buffer management (starvation and overflow) CS 414 - Spring 2012

Synchronization n Chapter 8 ¨ 8. 1 introduction, basic concepts of open and closed LDU, intra and inter-synchronization, ¨ 8. 2 requirements in synchronization, lip sync, ¨ 8. 5 synchronization types, ¨ 8. 7 reference models for multimedia synchronization, ¨ 8. 9 specification methods for multimedia synchronization n Interval-based, time-based, hierarchical, eventbased CS 414 - Spring 2012

P 2 P Streaming n n M. Castro, P. Druschel, A-M. Kermarrec, A. Nandi, A. Rowstron and A. Singh, "Split. Stream: High-bandwidth multicast in a cooperative environment ", SOSP'03, Lake Bolton, New York, October, 2003. H. Deshpande, M. Bawa, H. Garcia-Molina. "Streaming Live Media over Peers. " Technical Report, Stanford Info. Lab, 2002. N. Magharei, R. Rejaie. "PRIME: Peer-to-Peer Receiverdr. Iven MEsh-Based Streaming. " INFOCOM 2007. N. Magharei, R. Rejaie, Y. Guo. "Mesh or Multiple-Tree: A Comparative Study of Live P 2 P Streaming Approaches. " INFOCOM 2007. CS 414 - Spring 2012

Applications - major concepts n n S. Baset, H. Schulzrinne, "An Analasis of the Skype Peer-to-Peer Internet Telephony Protocol", 2004 Liu et al. "Opportunities and challenges of peerto-peer Internet video broadcast. " IEEE Special Issue on Recent Advances in Distributed Multimedia Communications, 2007. CS 414 - Spring 2012

Sample Problems n Buffer Management n Consider a multimedia file system. In this system, data for client requests are retrieved in cycles P ( P refers to the common time period of the whole system, e. g. , data for clients are retrieved every P=100 ms). If a client ‘i’ has the consumption rate fi (in bits per second) and there are k bits in the buffer at the start of a cycle, then the admission controller checks at the start of each cycle if k ≥ P x fi. With this admission test, what does the admission controller ensures? Explain. CS 414 - Spring 2012

Buffer Management Let us assume Video-on-Demand (VOD ) service with one client and one server. Let us assume that the server sends the Motion JPEG video at 20 frames per second and the client receives 20 frames per second. Let us assume that the end-to-end delay between client and server is 50 ms (in both directions) including the computational overheads on client and server side. Let us assume that the movie in fast forward (FF) mode uses stepskipping method and step is equal to 5 (e. g. if FF mode is triggered from the beginning, only frames will be played: 1 st, 6 th, 11 th, 16 th, etc). Under the above assumption, consider the following scenario: ¨ The client receives streaming video and plays it on the screen. Suddenly somewhere in the middle of the movie, the client switches to fast forward operation. What is the minimal buffer size (in number of frames) at the client side for this scenario, so that the movie in fast forward mode will continue to play the FF frames at the rate of 20 frames per second? n CS 414 - Spring 2012

Synchronization n Consider the following authored presentation: The presentation opens with Video and Audio playing concurrently for 10 minutes. After this play, slides are being shown one after another without any delays, narrated by audio in perfect sync. The presentation ends with animation and music that start concurrently, but then music continues to play for another 400 ms after animation finishes. Specify synchronization relations using time-axis specification. Specify synchronization relations using interval-based specification. CS 414 - Spring 2012

Other questions CS 414 - Spring 2012

Sample Problem – Media Server n Consider a true video-on-demand (VOD) service. To achieve true VOD, the multimedia designer must allow for any user to access the VOD service anytime and anywhere. The main challenge to achieve this design goal is to handle a large number of customers, and provide acceptable access latency. ¨ Specify two techniques to allow a true VOD service in terms of large number of customers, i. e. , explain how the techniques work and why you selected the techniques to handle large number of customers. CS 414 - Spring 2012

Multiple Choice – P 2 P n n n Consider the statement “Overlay multicast is faster than IP multicast approach. ” a. The statement is true. b. The statement is false. Consider the statement “In single tree P 2 P system all peers use equally outgoing bandwidth. ” a. The statement is true. b. The statement is false c. Peers do not care about outgoing bandwidth. The PPLive application relies on membership service which is placed at: a. Each peer b. A separate server c. The video source CS 414 - Spring 2012

Conclusion Good luck on your exam(s) !!!! n Have a great summer ! n CS 414 - Spring 2012