VALLIAMMAI ENGINEERING COLLEGE

VALLIAMMAI ENGINEERING COLLEGE SRM Nagar, Kattankulathur 603 203 DEPARTMENT OF ELECTRONICS AND COMMUNICATION ENGINEERING QUESTION BANK VIII SEMESTER EC6018 - MULTIMEDIA COMPRESSION AND COMMUNICATION Regulation 2013 Academic Year 2017 18 Prepared by Mr.A.Pandian, Assistant Professor (O.G) Dr. N. UshaBhanu, Associate Professor Dr.S. Ramesh, Associate Professor

UNIT I - MULTIMEDIA COMPONENTS Introduction - Multimedia skills - Multimedia components and their characteristics - Text, sound, images, graphics, animation, video, hardware. PART - A Q.No Questions BT Level Competence 1. What are the multimedia components? 2. Define multimedia and luminance. 3. Write the skill set requirements of multimedia designer and multimedia programmer. 4. Identify communication networks available for multimedia. 5. Describe the applications of multimedia and sampling rate. 6. List the types of text that are used to produce pages of documents. 7. Distinguish between unformatted text and formatted text 8. Summarize about three types of text that are used to produce pages of documents. 9. Interpret the pixel depth and aspect ratio. 10. Discuss raster scan principle. 11. Illustrate digitized documents. 12. Show how the quantization interval influences the accuracy of the sampling process of an analog signal. 13. Demonstrate the meaning of composite video signal. 14. Infer the three main properties of a color source that the eye makes use of and if you develop a multimedia team who are all must be therein that team? 15. Classify the digitization formats. 16. Differentiate between a bitonal image and a continuous-tone image. 17. Discriminate the additive color mixing and subtractive color mixing. 18. Assess the main features of the MIDI standard and its associated messages. BTL 5 BTL 5

19. Invent the color difference signal associated with the NTPC and PAL systems. 20. Formulate the resolution of luminance and chrominance signals for 525 and 625 line systems. PART - B 1. (i) What are the media types? (4) (ii) Describe the form of representation of media types that is used when all are integrated together and give your reason. What are basic skill set that a multimedia team should have? (12) 2. (i) List the basic types of communication network that are used to provide multimedia communication services. (4) (ii) Explain why most data networks operate in a packet mode. Hence explain why services involving audio and video are supported. (12) 3. (i) Identify the aim of all broadcast television networks. (3) (ii) Write some of the multimedia components. Explain some of the real time applications where these components can be used. (13) 4. (i) Examine the interpersonal communications may involve speech, image, text, or video for multimedia applications. (13) (ii) Name the three main categories of multimedia applications. (3) 5. (i) Discuss the interactive applications over the internet and entertainment applications of multimedia. (10) (ii) Distinguish the continuous media and block-mode media. (6) 6. (i) Describe the digitization principles. (10) (ii) Summarize the meaning of codeword, analog signal, signal encoder and signal decoder. (6) 7. (i) Express the meaning of unformatted text, and formatted text. (8) (ii) Interpret about the pages/documents, hypertext, and hyperlinks. (8) 8. (i) Illustrate the meaning of visual object, freeform object, clipart, and 3-D objects relating to graphical images and describe the procedural steps for creating 3D animation with neat sketches. (8) (ii) Show the digitization format for digitized documents through an example. (8) 9. (i) Demonstrate with the aid of diagrams where appropriate; explain the color gamut, additive color mixing, and subtractive color mixing. Give an application of both color mixing methods. (8)

(ii) Discover the raster scan operation associated with TV/computer monitors. (8) 10. (i) Compare the display resolutions and memory requirements for VGA, XGA & SVGA standard. (6) (ii) Analyze with the aid of a diagram, how a color image is captured within a camera or scanner and explain the working principle of digital camera & scanner. (10) 11. (i) Differentiate between 4:2:2 and 4:2:0 formats. (6) (ii) Classify the CD-quality audio and synthesized audio. (10) 12. (i) Explain the principle of operation of a PCM speech codec. Include in your diagram the operation of the compressor in the encoder and the expander in the decoder. (13) (ii) Pointout the PC video digitization formats. (3) 13. (i) Evaluate with the aid of diagram, the principles of interlaced of scanning as used in most TV broadcast applications. Include in your explanation the meaning of the terms filed, odd and even scan lines. Show the number of scan lines per field with for a 525 and 625 line system. (12) (ii) Assess the luminance, chrominance, and color difference and how the magnitude of each primary color present in the source is derived from these. (4) 14. (i) Generalise the following digitization formats: 4:2:2, 4:2:0, SIF, CIF, QCIF, and S-QCIF. (12) (ii) Develop the video content for particular application. (4) BTL 5

UNIT II - AUDIO AND VIDEO COMPRESSION Audio compression DPCM-Adaptive PCM adaptive predictive coding-linear Predictive coding-code excited LPC-perpetual coding Video compression principles-h.261-h.263-mpeg 1, 2, and 4. PART - A Q.No Questions BT Level Competence 1. What is the need for compression and principle of adaptive predictive coding? 2. Define pitch, period, loudness, and frequency masking. 3. List the audio compression techniques. 4. How the performance of a basic DPCM scheme can be improved by utilizing a more accurate version of the previous signal? 5. Identify the frame types in video compression. 6. Describe adaptive differential pulse code modulation encoder and decoder with a neat diagram. 7. Distinguish between LPC and CELPC. 8. Summarize the CELP based standards. 9. Interpret the frequency and temporal masking. 10. Discuss the Dolby AC-1, AC-2 and AC-3 standards. 11. Illustrate the I, P and B-frames and define & working of GOP with an example. 12. Discover the role of formatter. 13. Demonstrate the H.261 encoding formats. 14. Infer the ways of errors detected in H.263 video compression standard. 15. Classify the MPEG standards. 16. Differentiate MPEG-1 and MPEG-2 standards. 17. Discriminate MPEG audio and Dolby audio coders. BTL 5 18. Assess MPEG-4 decoder schematic. BTL 5 19. Develop B-frame encoding procedure in video compression. 20. Invent how reversible variable length codewords reduce the effects of transmission errors.

PART - B 1. (i) What is differential pulse code modulation? (3) (ii) Describe with the aid of a schematic diagram, the operation of a basic DPCM signal encoder and decoder. Include in your explanation the source of errors that can arise. (13) 2. (i) How better sound quality for the same bit rate can be obtained using a subband coding ADPCM. Give examples of the bit rates used for the lower and higher subbands and state an application of this type of codec. (6) (ii) Define adaptive PCM and explain ADPCM subband encoder & decoder with neat schematic. (10) 3. (i) Examine the third order predictive DPCM signal encoder and decoder schematic. (10) (ii) Write short notes on adaptive predictive coding. (6) 4. (i) Identify the perception parameters and associated vocal tract excitation parameters that are used. (8) (ii) List the terms relating to speech coders and explain the meaning. (8) 5. (i) Discuss the code excited linear predictive coding. (8) (ii) Distinguish between LPC and CELP codec. Include in your explanation the meaning of waveform template and template codebook. (8) 6. (i) Describe the LPC encoder and decoder with schematic diagram. (10) (ii) Summarize the principles on which perceptual coders are based and how they differ from an LPC and CELP coder. (6) 7. (i) Express the sensitivity of ear and frequency masking. (10) (ii) Interpret about the temporal masking with the support of a graph. (6) 8. (i) Illustrate a brief outline about the MPEG perceptual encoder and decoder. (12) (ii) Show the three levels of processing used and an applications and typical bit rate of each in MPEG perceptual coder. (4) 9. (i) Demonstrate the Dolby AC-1, Dolby AC-2, and Dolby AC-3. (12) (ii) Discover the difference between the forward adaptive bit allocation mode as used with an MPEG perceptual coder and the fixed bit allocation mode as used with a Dolby AC-1 coder. (4) 10. (i) Compare the H.261 & H.263 video compression standards. (4) (ii) Analyze the H.261 video encoder and infer the relation to the macroblock and frame formats. (12)

11. (i) Differentiate video encoding procedure used with motion vector and prediction vector. (4) (ii) Explain the compressed frames of I-frames, P- frames, B-frames and the reasons for their use. (12) 12. (i) Classify motion picture expert group standards. (3) (ii) Pointout H.263 error tracking scheme, independent segment decoding and reference picture selection with independent of segment decoding. (13) 13. (i) Evaluate the MPEG-1 frame sequence and video bit stream structure. (8) (ii) Assess about the compression technique which is used for regenerative sound and digital TV broadcast. (8) 14. (i) Develop how the content based video coding principle is done in video s and MPEG-4 coding. (12) (ii) Invent the compression algorithm used with MPEG-1 differs from that used in the H.261 standard. (4) BTL 5 UNIT III - TEXT AND IMAGE COMPRESSION Compression principles-source encoders and destination encoders-lossless and lossy compression-entropy encoding source encoding -text compression static Huffman coding dynamic coding arithmetic coding Lempel ziv-welsh Compression-image compression PART A Q.No Questions BT Level Competence 1. Define the term Entropy encoding. 2. What is meant by temporal redundancy? 3. List out the methods in source encoding. 4. Define entropy. How entropy is related for the performance measure of statistical encoding? 5. What are the main objectives of lossless and lossy compression techniques? 6. Give the principle of differential encoding. 7. Summarize the significance and applications of GIF and TIFF image file formats. 8. Outline the basic principle of Statistical encoding. 9. State the principle of Progressive transmission. 10. When prefix code is called as optimum prefix codes? 11. Identify the applications of LZW. BT3 12. Develop the expression for coding efficiency to entropy. BT3 13. If there is a ZIP code file format means which kind of compression technique is used to unzip the data. BT3 14. In what way the adaptive Huffman code differs from Huffman BT4 code? 15. Distinguish between static and dynamic Huffman coding. BT4

16. What is the need of EOL in Facsimile machine? BT4 17. Justify the need of dictionary based algorithm. BT5 18. Assess the need of run length encoding? For which type of BT5 applications it is more useful? Justify. 19. Create the expression for DCT of each 8X8 block values. BT6 20. Propose the frame format for JPEG. BT6 PART B 1. Define the following: i. Source encoders & destination decoders (4) ii. Lossless and Lossy compression techniques (4) iii. Entropy Encoding (4) iv. Source Encoding (4) 2. (i) Explain JPEG encoding process in detail. (8) (ii) Explain why differential encoding is used for the compression of the DC coefficient in successive blocks. (8) 3. With the aid of diagram explain in a qualities way the meaning of the following terms relating to transform encoding. (i) Spatial frequency (4) (ii) Horizontal & vertical components (4) (iii) DCT (8) 4. Give a detailed note on the following image file formats: (i) GIF (8) (ii). TIFF (8). 5. Explain in detail about various image compression techniques.(16) 6. Summarize the principle of : i. Arithmetic coding. (6) ii. LZW algorithm. (10) 7. Explain the following terms relating to facsimile machines: (i)termination codes (4) (ii) make-up codes (4) (iii) Over scanning (4) (iv) EOL code and its uses (4) 8. A series of messages is to be transferred between computers. The message comprises of the characters a through f. The probability of occurrence of the characters a through f are 0.4, 0.2, 0.1, 0.1, 0.1, 0.1 respectively. Use Huffman coding procedure to derive a codeword and also obtain the average codeword length. (16) BT3

9. (i) The following character string is to be transmitted using Huffman coding A B A C A D A B A C A D A B A C A B A B. Compute and draw the Huffman code tree. (10) (ii) With an example, explain Shannon- Fano Coding (6) 10. Consider the string : ARBER, analyse Huffman coding and decode it. (16) BT3 BT4 11. Find Huffman code word of the given text AAAAAAAAAABBBBBCCCSS by using static Huffman tree. Calculate Entropy and derive the average number of bits per character for code word? (16) 12. Examine the basic mode of operation of GIF. Include in your explanation the size of the color table used, how each pixel value is sent, and how the receiver knows the image parameters used by this source. (16) 13. Explain the importance of arithmetic encoding algorithm and encode the string with the probabilities of the character went$. The probabilities are : e=0.3, n=0.3, t=0.2, w=0.1, $=0.1 (16) BT4 BT4 BT5 14. Messages comprising Seven different characters, A through G are to be transmitted over a data link, analysis has shown that the relative frequency of occurrence of each character is A 0.10, B 0.25, C 0.05, D 0.32, E 0.01, F 0.07, G 0.2 a. Derive the entropy the messages (4) b. Use static Huffman coding to derive a suitable set of code words (4) c. Derive the average number of bits per code word for four code word set to transmit a message (4) d. compare this with the fixed length binary code words. (4) BT6 UNIT IV - VOIP TECHNOLOGY Basics of IP transport, VoIP challenges, H.323/ SIP Network Architecture, Protocols, Call establishment and release, VoIP and SS7, Quality of Service- CODEC Methods- VOIP applicability PART A Q.No Questions BT Level Competence 1. What are the major challenges involved in the implementation of VOIP?. 2. Write the applications of VOIP in multimedia systems. 3. Draw the network architecture for SIP. 4. Describe Real Time Transport Protocol. 5. Point out the commands used in MEGACO.

6. Draw OSI- IP protocol stack for voice transport. 7. What do you mean by Real Time Transport Protocol? 8. Which is the first successful set of protocols for VOIP? How it is called in another way? 9. Define media descriptor in MEGACO. 10. Summarize all CODEC methods. 11. Illustrate the role of ARQ in H323. BT3 12. Classify and describe the SIP basic classes. BT3 13. Sketch the H.323 network architecture with neat diagram. BT3 14. Analyse the need and draw the SIGTRAN protocol suite. BT4 15. Categorize the commonly used CODEC s and its features. BT4 16. How does a call establishment take place in VOIP? BT4 17. Justify how QOS is measured in VOIP. BT5 18. Explain soft switch architecture. BT5 19. Formulate MEGACO protocol context and termination. BT6 20. Discuss the features of SS7 and its applications. BT6 PART B 1. (i) Give a detailed note on challenges in VOIP and its applications. (10) (ii) Write a brief note on QoS issues in VOIP. (6) 2. (i) Define and explain the architecture of SIP. (10) (ii) List the Various CODEC methods. (6) 3. Write short notes on: i. SCTP (6) ii. MPLS (10) 4. Explain the following in MEGACO protocol. (i) MEGACO transaction (4) (ii) MEGACO commands (4) (iii) MEGACO descriptions (4) (iv) MEGACO call establishment.(4) 5. Explain the H.323/ SIP network architecture along with protocol stack with neat diagram. (16) 6. (i) Summarize the basics of SS7 signaling and describe its applications in VOIP. (8) (ii) Explain the call establishment and release phase of VOIP connection with neat diagram. (8) 7. Explain the SIP messages and address formats. Describe the session establishment, termination and call tracking using SIP.(16) 8. Identify the meaning of the source descriptor items used in RTCP source description packet. Specifically find the meaning of CNAME, NAME, EMAIL, PHONE, LOC, TOOL, NOTE & PRIV.(16) 9. What are the features of MEGACO protocol? Explain the techniques involved in MEGACO protocol.(16) BT3 BT3

10. (i)discuss the terminology and concept behind VOIP network architecture. (8) (ii)explain basics IP transport in detail? (8) BT6 11. (i) How the call establishment will be carried out in H.323. Explain in detail. (8) (ii) Analyse the fast connect procedure of H.323 with necessary diagrams. (8) 12. Determine the format of RTCP sender and give description to the packet length and the fields repeated for each source. Describe each field. (16) 13. (i) Examine the types of CODEC s for handling VOIP traffic.(8) (ii) How SIGTRAN is related with IP & SS7? Explain. (8) 14. Compare the similarities and differences of UDP and RTP with TCP/IP. Justify your answers. (16) BT4 BT4 BT4 BT5 Analysing UNIT V - MULTIMEDIA NETWORKING Multimedia networking -Applications-streamed stored and audio-making the best Effort service-protocols for real time interactive Applications-distributing multimedia-beyond best effort service-secluding and policing Mechanisms-integrated services-differentiated Services-RSVP. PART A Q.No Questions BT Level Competence 1. List out the schemes for streaming stored media & name the advantages of each scheme 2. Recall the link scheduling discipline methods. 3. Define packet jitter. 4. What is mean by RSVP? 5. Show the limitation of best effort service. 6. Outline the features of best effort service. 7. Summarize the important points about interactivity for streaming stored audio/video. 8. Discuss the meaning of interactivity for real time interactive audio/video. 9. Explain the role of the DNS in CDN. 10. Classify the different RTP stream in different session identified by a receiver. 11. Illustrate the role of SIP register.

12. Interpret the header fields in RTP through proper diagram. 13. How will you distinguish RTP & RTC packets? 14. Analyse the causes of packet jitter. Analysing 15. Categorize the difference between end to end delay & packet jitter. Analysing 16. Choose some of the difficulties associated with the inserv model and Analysing per-flow reservation of resources. 17. Briefly explain the removal of jitter at the receiver for audio. BTL 5 18. What are the 3 approaches that can be used to support Multimedia BTL 5 applications? 19. Discuss how the role of an SIP register is different from that of a home agent in mobile IP. 20. Elaborate about streaming of Audio/Video. PART B 1. i) Explain the interactivity for streaming stored audio/video for real time interactive applications. (8) (ii)write short notes on (a) Real time streaming protocol (2) (b) Decompression (2) (c) Jitter removal (2) (d) Quantization (2) 2. (i) List out RTCP packet types. (4) (ii) Explain the information contained in RTCP packet types.(12) 3. Explain intserv model and per-flow reservation of resources. (16) 4. (i) How the performance of audio quality can be recovered from packet loss? (8) (ii) Mention the procedures to be followed for quality maintenance of Audio. (8) 5. Give a detail notes on Multimedia protocols for real time interactive application with an example. 6. Summarize the important points on : (i) Leaky bucket (4) (ii) WFQ (4) (iii) SIP (4) (iv) H323 (4) 7. Give a brief note on integrated and differential service. (8) Explain the principle and applications od RSVP. (8) 8. (i) Explain the various scheduling mechanisms. (8) (ii) What are the policing mechanisms used in multimedia networking? Summarize. (8) 9. Apply the knowledge on RTCP concepts to solve the problem. Consider an RTP session consist of 4 users, all of which are sending and receiving RTP packets in to the same Multicast address, each user sends video at 100 kbps. (i) What is the rate of RTCP to limit the traffic? (4) (ii) How much RTCP bandwidth will be allocated for particular

receiver? (6) (ii) How much RTCP bandwidth will be allocated for a particular sender? (6) 10. (i) What would be pre-emptive priority queuing? (6) (ii) Inspect the pre-emptive priority queuing for computer networks. (10) 11. (i) Compare RTSP and HTTP. (4) (ii) Examine the process of RTSP to maintain the state information about the client (12) 12. (i) Analyse any one of the protocols for real time interactive applications with suitable diagrams. (8) (ii) Examine the motivation of packet jitters. (8) 13. (i) Criticize on how the jitter can be removed from audio at the receiver end. (8) (ii) Construct the planning of the inter arrival time jitter in RICP reception report. (8) 14. Explain the possibility for CDN to provide worse performance to a host requesting a Multimedia object than if the host has requested the objects from the distant origin server? (16) BTL 5