Multimedia Networking Practice Mid-Semester Exam

1. From [LE91], what are two major types of redundancy that video compression techniques, such as MPEG, take into account in order to achieve high compression rates?

2. From [Rs75] and your project 1 (Speech Detection), given a zero-line of 127 and the following samples:

      137
      127
      117
      147
      187
      77
   

   1. What is the energy level?
   2. If the upper energy threshold (ITU) is 100, is this speech or silence?
   3. Besides energy level, what other metric is used to determine the endpoints of speech?

3. In [WS00], the relative effects of numerous degradations to speech over the Internet were compared. Order the following degradations from the least damaging to most damaging:

       echo
       5% loss
       bad microphone
       loud
   

4. Both loss and jitter are known to degrade the quality of interactive multimedia applications. The work in [CT99] compares the effects of loss and jitter on the perceptual quality of video. Briefly describe their main finding.

5. Give 2 reasons why TCP is generally less than ideal as a transport protocol for interactive streaming multimedia.

   Give 2 reasons why UDP is generally less than ideal as a transport protocol for high-bandwidth streaming multimedia.

   Based on [PFOC00], give 1 reason why SRP is an improvement over both TCP and UDP.

6. Briefly explain the motivation behind the work in [LPHT95]. In other words, why did the authors conduct a survey of over 400 research articles from both computer science and non-computer science disciplines?

References

RS75

Le91

LHPT95

WS00

CT99

LR01

MH00

PFOC00

FHPW00

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