1

MULTIMEDIA SYSTEMS

QCODE: 695

SUBCODE: 35281

PART-A

Each question carries 2 marks. Answer five question. Q.no.8 compulsory.

1. What is virtual reality?

Virtual reality is a system that gives the user the feeling of being in control of the

environment or the environment interacting in response to the user’s action (a sense of real

environment).

2. What is OpenGL?

OpenGL (Open Graphics Library) is a cross-language and cross-platform API

(Application Program Interface) used for defining 2D and 3D graphics images.

3. What is cell-based animation?

Cell-based animations consists of multiple drawings, each one a little different from

others. When displayed in rapid sequence the drawings appear to move.

4. What is the need for compression?

(Any two)

1. To reduce the file size

2. To reduce the amount of required storage

3. To increase the speed of data access

4. To increase the speed of data transmission through network

5. To reduce the storage cost and transmission cost.

5. Expand PNG.

PNG-Portable Network Graphics

PNG format is used for high resolution graphics images and animation.

6. What is the function of DSP?

Digital Signal Processor (DSP) controls the contrast and other details of the image and

compress it. Then the image is stored as files such as JPG and GIF.

7. What is client side scripting?

The scripting programs that run at the client machine is called client-side scripting.

8. What is MOD?

Media on demand is a system that allows the user to select and watch the audio or video

contents.

PART-B

Each question carries 3 marks. Answer five questions. Q.no.16 compulsory.

9. What is 3D technology? How is holography related to 3D technology?

If the pixel of an image is represented by three coordinate values X, Y, Z then it is a 3D

image.

Photographic recording of the light field of an image is known as hologram.

2

Holography is a technique of creating 3D images by applying light effects, laser beam

and optical illution on a photographic image.

10. Explain briefly about

(a) Dithering

Dithering is the process of changing the unavailable colors into the closest

available colors.

This is done by the help of color palette.

(b) Rendering

The process of converting 3-D objects into 2D objects on a computer display

with the realistic effect is called rendering.

11. What is object based animation?

Object based animations are created by moving an object across a screen. This type of

animations is usually seen in computer games.

For example, a car moving across the screen. In this animation only one picture is drawn.

Then the entire picture is moved slowly.

12. List down the advantages and disadvantages of fractal compression.

Advantages

Compression ratio is very high

Non-lossy compression.

Function are image resolution independent

When expanding the image, sharpness does not change.

Disadvantages

It takes longer time for compression

Asymmetric compression.

13. Write briefly about social media sharing.

Multimedia files are transferred and shared using storage devices such as CD, DVD and

pen drives. It becomes easy to share multimedia files using social media networks such as

Whatsapp, tweeter, facebook etc. Information can be shared through social media using

computers as well as mobile phones.

14. Explain the working of active LED matrix display.

An active LCD matrix display contains 640 x 480 pixels same as passive LCD matrix

display. It is faster than passive LCD matrix system because the number of transistors used is

very high.

For example there are 640 x 480 x 3 = 921600 transistors used for VGA and 800 x 600 x

3 =1,440, 000 transistors used for SVGA display.

15. Discuss briefly about bandwidth bottleneck.

Bandwidth is defined as the amount of data that can be transmitted in a given period of

time. It is usually measured in bits per second (bps).

Bottleneck is a situation occurring in a transmission medium when the bandwidth of

incoming data is very lower than the receiving end.

Bottleneck generally occurs due to poor transmission medium like telephone medium.

3

16. Compare MIDI and digital audio.

[Any Three]

S. No MIDI Digital Audio

1 Smaller file size 200 to 1000 times larger than MIDI.

2 Requires less CPU resources More CPU resources required

3 Can be load and play quickly on web

pages

Slower performance on web pages.

4 Quality depends on the synthesizer Quality depends on the file format

5 Does not support spoken dialogue Supports spoken dialogue

6 Less number of software tools available

for editing MIDI.

Very large number of software tools

available for editing digital audio.

7 Musical knowledge must be required. User need not be having musical

knowledge.

PART-C

Each question carries 10 marks. Answer division (a) or division (b).

17. (a) (i) Explain the various multimedia elements. [Any five] [5m]

Multimedia applications require dynamic handling of data consisting of a mix of

text, voice, audio components, video components and image animation.

Based on the definition of multimedia, its elements fall into 10 categories.

Fascimile: FAX was the first practical means of transmitting document images over

telephone lines. This basic technology has lower dpi of 100 to 200.

Document Images: Document images are used for storing business documents that must

be retained for long periods of time or may need to be accessed by a large number of

people. Providing multimedia access to such documents removes the need for making

several copies of the original for storage or distribution.

Photographic images: Photographic images are used for a wide range of applications-

such as employee records for instant identification at a security desk, real estate systems

with photograph of houses in the database containing the description of houses and

medical case histories.

Geographic information systems map: Map created in GIS systems is being used

widely for natural resources and wild life management as well as urban planning. The

map containing database items contains wildlife statistics or details of the floors and

rooms and workers in an office building.

Voice commands and voice synthesis: Voice synthesis is used for presenting the results

of an action to the user in a synthesized voice. Application such as a patient monitoring

system in a surgical theatre will be prime beneficiaries of these capabilities. Voice

commands allow the user to direct computer operation by spoken commands.

Audio message: annotated voice mail already uses audio or voice messages as

attachments to memos and documents such as maintenance manuals.

Video messages: they are being used in a manner similar to annotated voice mail.

Stored and live full-motion video: Stored full-motion videos are used for e-mails and live

full-motion videos are used for presentations and video conferencing.

Fractals: The objects that are stored as computer generated algorithms are known as

fractals.

4

(ii) Explain in detail about the structure of a VRML file. [5m]

A VRML file contains the following

The file header

Comments - remarks to the user

Nodes - Scene information

Fields - Attributes of the node

Values - Values of the attributes

Node name - Names of the nodes.

Example

The following VRML code is written to create a 3D cylinder.

#VRML V.20 ut f8

#A cylinder

Shape

{

Appearance

{

Material matrial

{}

Geometry cylinder

{

Height 2.0

Radious 1.5

}

}

}

(Or)

(b) (i) Explain in detail about hypermedia documents. [5m]

Hypermedia documents are computer based documents that contains

text, graphics, audio and video on pages that are connected by navigational links

called hyperlinks. These links allow multiple views and non-linear interactions of

information. Hypermedia documents can be printed, written, read, sent and

received in electronic form through networks. Hypermedia documents are the

electronic documents that contain not only text but linked multimedia objects

such as image, audio and full-motion video.

The multimedia document with rich set of interlinks and hyperlinks is known as

hypermedia document. Hypermedia document contains HYPERTEXT and

HYPERSPEECH.

5

Hypertext – Text that contains link with another document or another page of the

same document is known as Hypertext.

Hyperspeech – is a speech only hypermedia application that explores issues of

speech user interfaces and navigations.

(ii) Write short notes on Windows and open source API. [5m]

The open source helpers like mGitHub and SourceForge provide

invaluable resources for those searching for assistance in creating their own

applications.

Most popular development tools, mobile development tools, APIs, text

editors and IDEs are available in open source.

Some of the Microsoft open source. Software are below.

(a) Software Development – GW-BASIC, JSript, VBscript, visual studio,

Visual Studio, Visual C#, Visual J#, Visual J++, Windows API.

(b) 3D softwares – Microsoft Softimage, Direct 3D, Windows 3D Builder,

Microsoft VRMI 2.0, Holo studio.

(c) Operating Systems – MS-DOS, Windows NT, Windows CE, Windows

Mobile, Windows XP, Windows 7, Xenix.

(d) Windows Components – Internet Explorer, Calculator, Paint, Notepad,

Windows Chat, Windows Media Player.

18. (a) (i) Explain about hypertext tools. [5m]

Hyper text writers need to work with complex structures. Hypertext tools

are used to displaying and manipulating these hypertext structures.

Example: Storyspace, Eastgate web squirrel

These tools are used to build the complex structures through direct manipulation.

Instead of describing the structure., the winter just up pick up the objects on the screen,

drag them into other objects or draw connection between the objects. The following

figure shows creating structure using the hypertext tool story space

In the above figure, the user paced nine objects and drew the links among them.

6

(ii) Write briefly about colour image processing. [5m]

Color image is a digital image in which each pixel having colour

information. A colour image has three values per pixel, they measure the intensity,

chrominance and brightness of light.

A colour image is usually stored in memory as a two dimensional array

of small integer triplets. The number of bits used to indicate the colour of a single pixel is

known as colour depth. Colour image processing includes the following:

Colour balance: It is the adjustment of the intensities of the primary colors Red, Green,

Blue.

Colour mapping: It is a function that transforms the colors of one image to the colors of

another image.

Colour normalization: It is a function that is used to compensate the variations in colour

values of each pixel.

Colour constancy: It allows the user to assign a constant colour to the object even under

different illumination conditions.

Colour Quantization: This is a process that reduces the number of distinct colours in an

image.

Colour indexing: In this technique, colour information is not stored in the pixel data, but

it is stored in a separate piece of data called palette. This is only for memory saving

purpose.

Colour moments: This technique is used for scaling and rotating the colour images using

algorithms.

(b) (i) Explain the various audio formats supported by internet. [5m]

The sound formats supported by internet are based on the web browser. There are

various sound formats supported by internet.

The WAVE Format: The WAVE format was developed by IBM and Microsoft. It is one

of the more popular formats it is not only supported by computers running the windows

operating system, but also by all popular web browsers. Files in the wave format have the

extension .WAV

The MP3 Format: This format is developed by Motion Pictures group for storing music.

They offer good compression and high quality. They are supported by most popular web

browsers. The MP3 files have the extension .MP3.

The windows media format: the windows media format was developed by Microsoft. It is

one of the very popular formats on the internet and on computers with the windows

operating systems. It should be noted that this format requires the installation of an

additional components in non-windows computers. Files in the windows media format

have the extension .WMV

The MIDI format: The Musical Instrument Digital Interface is an internationally

accepted file format used to store MIDI data. Most of the popular browsers support MIDI

files. These files are stored with extension .MID.

The shock wave format: The shock wave format was developed by Macromedia and is

used to store multimedia components created using Flash. This format requires an extra

component to play. The additional component comes preinstalled with the latest version

of Netscape and Internet Explorer Files in the shockwave format have the extension

.SWF.

(ii) Explain briefly about image enhancement. [5m]

The process of improving the quality of a digitally stored image is known

as image enhancement. For example to increase or decrease the contrast of the image, to

make an image lighter or darker etc.

7

Advanced image enhancement software tools are available, to provide better

human view and better input images to multimedia projects.

Image enhancement includes:

Image stretching: It is also known as normalization that is used to change the range of

pixel intensity values of an image. This technique is used to improve the contrast of a

photograph with poor contrast.

Image sharpening: Sharpening is a technique for increasing the apparent sharpness of an

image. It is done by increasing the resolution and acutance.

Image shrinking: Shrinking is the process of decreasing the contrast by making brighter

pixels less bright and darker pixels less dark.

Image sliding: Sliding is the process of changing the overall visible effects by

brightening or darkening the image.

Image Scaling: Scaling is the process of enlarging or shrinking the whole part of an

image.

Image rotation: Rotation is the process of rotating the whole image about a center point.

Image Filtering: Filtering is the process of reducing the noise and highlighting the edge

of an image.

19. (a) (i) Explain non-lossy compression schemes. [5m]

Non-lossy compression is a standard that can retain all information in the original

multimedia object.

The CCITT (International consultative Committee for Telephone and Telegraph)

group introduced many algorithms for non-lossy compression.

CCITT Group2

It is very earlier compression scheme for low resolution images. It is not in use

anymore.

CCITT Group 3 – ID

This compression scheme is used for black and white images. It is also known as

run-length encoding.

CCITT Group 3 – 2D

This compression scheme is used for document imaging systems. It is also

known as modified run-length encoding. This compression gives a better compression

ratio.

CCITT Group 4

This compression is a 2D coding scheme for images with high resolution. This

scheme also gives the best compression ratio.

CCITT Group 5

This compression scheme is used for gray scale and 256 colour images.

(ii) Explain TWAIN architectures. [5m]

The multimedia objects such as text, images, audio and video are created

and captured using different types of input devices such as scanners, cameras and

microphones. When data are created from different sources with the help of

different software applications, the data had to be stored in a number of disk files.

The stored data can be accessed by different applications at anytime through

network. This is very complex and conjuctive.

The architecture of TWAIN is shown in the following figure.

8

Application Layer

This layer makes the connection between the application and device.

Protocol Layer

It is the most important layer in the TWAIN architecture. This layer is

responsible for communication between the application layer and the acquisition

layer.

Acquistion Layer

This layer contains the virtual device driver to interacts directly with the

device driver. This layer is also called source layer.

Device Layer

The purpose of device layer is to receive the software commands and

control the device hardware accordingly.

(b) (i) Explain briefly about JPEG compression. [5m]

JPEG is a compression standard for colour and gray scale images. It is a

lossy compression. The major concept of this compression scheme is removing

the data redundancy.

The JPEG compression algorithm is done through three major steps.

Discrete cosine Transform (DCT)

Quantization

Entropy Encoder

Discrete Cosine Transform

DCT is a mathematical function that removes the data redundancy by

transforming data from the spatial domain to a frequency domain.

Quantization

Quantization is the process of determining whether the information

discarded by DCT without a significant loss of visual performance. Quantization

is done by a Quantizer that uses many-to-one mapping fundamental.

Entropy Encoder

Entropy is defined as a measure of disorder, randomness and the measure

of systems ability. The Entropy encoder compresses the quantized DCT

coefficients.

9

The following figure shows the JPEG compression methodology.

The JPEG compression is a symmetrical algorithm that means the

decompression is the exact reverse process of compression.

(ii) Explain in detail about user generated media content sharing. [5m]

User generated content (UGC) or User Created Content is any form of

content created by the users of a system and made available publicly on that

system.

The content may be images, videos and audios and they can be shared to

online platforms such as any social media web sites.

UGC is used for a wide range of applications including news,

advertising, entertainment and research. Social media sites like Face book,

Twitter and Instagram allows the user to interact with other people chatting,

messaging and image postings.

Media hosting sites such as YouTube allow users to post media contents.

The following figure shows that how much do sites profit from UGC in 2010.

Advantages of UGC

Better understanding of the customer

More site engagement

Increased customer satisfaction

Stronger community

Increasing SEO.

20. (a) (i) Explain the various types of video image processing. [5m]

Image processing is a process of manipulating images such as brightening, sharpening

and other several image operations.

Types:

1. Pixel processing

2. Interframe image processing

3. Frame processing

4. Filter processing

Pixel Processing

Histogram sliding: Histogram sliding is used to change the overall visible effect

by brightening or darkening of the image.

10

Histogram stretching: Histogram stretching is used to increase the contrast by

making the brighter pixels even more brighter and the darker pixels even more

darker.

Histogram shrinking: Histogram shrinking is the process of decreasing the

contrast by making the brighter pixels less bright and darker pixels less dark.

Pixel threshold: Pixel threshold is the process of set a limit on the bright and

darkness of a picture.

Interframe image processing

Image averaging: Image averaging is the process of minimizing the effect of

random noise.

Image subtraction: Image subtraction is the process of determining the change

from one frame to the next frame.

Frame Processing

Image scaling: Image scaling is the process of enlarging or shrinking the whole

part of an image.

Image rotation: Image rotation is the process of rotating the whole image about a

center point.

Image translation: Image translation is the process of moving the image from up,

down, left or right.

Filter processing

Low pass filter: Low pass filter is used to blurring the image by reducing noice.

High pass filter: High pass filter is the process of emphasizing the edges of an

image.

Laplacian Filter: Laplacian filter is the process of highlighting all edges of an

image.

(ii) Write about instant multimedia. [5m]

Size of a multimedia project is measured by the duration of development process and

number of persons in the team. Mostly multimedia projects are developed in a couple of

weeks or months by a team of 10 to 20 members. Some multimedia projects are

developed in a couple of hours by a single person. This product is called Instant

Multimedia.

Instant multimedia projects need the following requirements.

1. Developer must have skill in all types of multimedia tools such as text

editing tools, audio editing tools, movie editing tools and animation tools.

2. Computers must be able to run all types of multimedia software.

3. Computers must have all types of multimedia related devices.

4. Computers must have a large number of collections in already captured

images, audio, videos and clipart.

(b) (i) Explain the architecture of a video capture board. [5m]

A full-motion video capture board is a circuit card that is used to capture videos. It

consists of the following architecture.

Video input

S-video input

Video compression decompression processor

Audio compression-decompression processor

ADC

DAC

Audio input

11

The following figure shows the architecture of video capture board.

Video input-Video input system accepts video signals in RS170 standard. Video

compression decompression processor- Video compression and decompression processor

is used to compress and decompress the video data. Audio compression-decompression

processor- Audio compression and decompression processor is used to compress and

decompress the audio data. ADC- (Analog to digital converter) converts the input data

into digital. DAC- (Digital to analog converter) converts the digital data into analog for

output. Audio input- Audio input system accepts audio inputs from microphone, line-in

and CD-in.

(ii) Explain how multimedia applications are produced for web. [5m]

Multimedia applications can be developed for the web that means they can be

accessed through internet.

To create web based multimedia applications the following languages are used.

HTML (Hypertext Markup Language)

XML (Extensible Markup Language)

Java

Java script

AJAX (Asynchronous Java Script And XML)

CSS (Cascading Style Sheet)

ASP (Active Server Pages)

12

21. (a) (i) Explain the various user interfaces. [5m]

User interface can be done by the following.

Menus

Dialog boxes

Buttons

Icons

Menus

Menus are the most common elements in multimedia user interface. Menus are

used for grouping the commands so that the user can easily access them. Each command

in the menu is called menu items. When the user selects a menu item the corresponding

operation is processed.

Dialog Boxes

Dialog boxes are small text boxes that provides place to the user for entering any

information.

Buttons

Buttons are the small clickable text that is covered by a rectangle. When the user

clicks a button the corresponding action will be performed.

Icons

Icons are the graphical symbolic representation of processes. When clicking an

icon, the corresponding process is executed.

(ii) What are the various factors to be considered when adding video on web? [5m]

When adding video on web, the developer must consider the following:

Video must be compressed for increasing the bandwidth.

Use high speed cable modems for internet connection.

Convert the video file format into MPEG format.

Avoid using more video files in an application.

Edit the video such as trimming, cutting before embedding the video in

the application.

b. (i) Define plug-in. Explain its types. [5m]

Plug-ins are helper applications that are used by browsers to view and

interact with new types of documents and images. With the help of plug-ins,

browsers can view any type of information.

Types:

There are several plug-ins

Text Plug-ins

Image Plug-ins

Sound Plug-ins

Text Plug-ins

Text plug-ins are used to download large text documents with special

fonts.

Example: Adobe Acrobat Reader

Acrobat Reader is a plug-in that is used to deliver a text document from internet

to the client in the PDF format.

Image Plug-ins

Image plug-ins are used to enable viewing the vector formats. They are

used to decompress the images and display on client machine.

Example: Adobe Photo-viewer

13

Sound Plug-ins

Sound plug-ins are used to receive and playback any kind of sound files

from the web.

Example: Windows Media Player, Real-time Player etc.

(ii) Explain briefly about E-learning and education. [5m]

A learning system with the help of electronic resources instead of traditional

class room is known as E-Learning.

E- Learning can be termed as a network based transfer of skills and knowledge in

which education is delivered to a large number of recipients at the same or different time.

Advantages of E-learning:

Web based distance education

No face-to-face interaction

Flexible timing and place

Students can share their problems with teachers

Faster delivery of notes and syllabus

Lower cost

Lower environmental impact

Not necessary for physical presence to the class room.

---------------------------

Prepared by

PUSHPA SHEELA E [41205212]

Part Time / Guest Lecturer

120, Government Polytechnic College,

Purasawalkam, Chennai – 12.