2marks_cg

8/2/2019 2marks_CG

1/8

Computer Graphics Department of CSE

TWO MARKS QUESTIONSUNIT I

1. Define Computer graphics.Computer graphics remains one of the most existing and rapidlygrowing computer fields. Computer graphics may be defined as apictorial representation or graphical representation of objects in acomputer.

2. Name any four input devices.Four input devices are keyboard, mouse, image scanners, andtrackball.

3. What is resolution? The maximum number of points that can be displayed without overlapon a CRT is referred to as the resolution.

4. Write the types of clipping?Point clipping, line clipping, area clipping, text clipping and curveclipping.

5. Define pixel?Pixel is shortened forms of picture element. Each screen point isreferred to as pixel or pel.

6. What is frame buffer?Picture definition is stored in a memory area called frame buffer orrefresh buffer.

7. What is point in the computer graphics system? The point is a most basic graphical element & is completely definedby a pair of user coordinates (x, y).

8. Write short notes on lines?A line is of infinite extent can be defined by an angle of slope q andone point on the line P=P(x,y). This can also be defined as y=mx+Cwhere C is the Yintercept.

9. Define Circle?Circle is defined by its center xc, yc and its radius in user coordinateunits. The equation of the circle is (x-xc) + (y-yc) = r2.

10. What are the various attributes of a line? The line type, width and color are the attributes of the line. The linetype include solid line, dashed lines, and dotted lines.

11.What is Transformation? Transformation is the process of introducing changes in the shape

size and orientation of the object using scaling rotation reflectionshearing & translation etc.

12. What is translation? Translation is the process of changing the position of an object in astraight-line path from one coordinate location to another. Everypoint (x , y) in the object must under go a displacement to (x|,y|). thetransformation is: x = x + tx ; y = y+ty.

13. What is rotation?

A 2-D rotation is done by repositioning the coordinates along acircular path, in the x-y plane by making an angle with the axes. Thetransformation is given by:X = r cos (q + f) and Y = r sin (q + f).

P a g e | 1

8/2/2019 2marks_CG

2/8


14. What is scaling?A 2-D rotation is done by repositioning the coordinates along acircular path, in the x-y plane by making an angle with the axes.

The transformation is given by:X = r cos (q + f) and Y|= r sin (q +f).

15. What is shearing? The shearing transformation actually slants the object along the Xdirection or the Y direction as required. ie; this transformation slantsthe shape of an object along a required plane.

16. What is reflection? The reflection is actually the transformation that produces a mirrorimage of an object. For this use some angles and lines of reflection.

17. Distinguish between window port & view port?A portion of a picture that is to be displayed by a window is knownas window port. The display area of the part selected or the form inwhich the selected part is viewed is known as view port.

18. Define clipping?Clipping is the method of cutting a graphics display to neatly fit apredefined graphics region or the view port

19. What is the need of homogeneous coordinates? To perform more than one transformation at a time, usehomogeneous coordinates or matrixes. They reduce unwantedcalculations intermediate steps saves time and memory andproduce a sequence of transformations.

20. Distinguish between uniform scaling and differentialscaling?When the scaling factors sx and sy are assigned to the same value,a uniform scaling is produced that maintains relative objectproportions. Unequal values for sx and sy result in a differentialscaling that is often used in design application

21. What is fixed point scaling? The location of a scaled object can be controlled by a position calledthe fixed point that is to remain unchanged after the scalingtransformation.

22. What is Zooming?

Zooming means enlarging a digital image to see it more clearly ormake it easier to alter. It allows the user to see more detail for aspecific area of the image.

23. What is Rubber Banding?Rubber Banding is another form of zooming. The user can use amouse to define two corners of a rectangle. The selected area canbe copied to a clipboard, cut, moved or zoomed.

UNIT II1. Define Projection?

The process of displaying 3D into a 2D display unit is known as

projection. The projection transforms 3D objects into a 2D projectionplane2. What are the steps involved in 3D transformation?

Modeling Transformation

P a g e | 2

8/2/2019 2marks_CG

3/8


Viewing Transformation Projection TransformationWorkstation Transformation

3. What do you mean by view plane?A view plane is nothing but the film plane in camera which ispositioned and oriented for a particular shot of the scene.

4. Define projection? The process of converting the description of objects from worldcoordinates to viewing coordinates is known as projection

5. What you mean by parallel projection?Parallel projection is one in which z coordinates is discarded andparallel lines from each vertex on the object are extended until theyintersect the view plane.

6. What do you mean by Perspective projection?Perspective projection is one in which the lines of projection are notparallel. Instead, they all converge at a single point called the centerof projection.

7. What is Projection reference point?In Perspective projection, the lines of projection are not parallel.Instead, they all converge at a single point called Projectionreference point.

8. Define computer graphics animation?Computer graphics animation is the use of computer graphicsequipment where the graphics output presentation dynamicallychanges in real time. This is often also called real time animation.

9. What is tweening?It is the process, which is applicable to animation objects defined bya sequence of points, and that change shape from frame to frame.

10. Define frame?One of the shape photographs that a film or video is made of isknown as frame.

11. What is key frame?One of the shape photographs that a film or video is made of the

shape of an object is known initially and for a small no of otherframes called keyframe12. Define Random scan/Raster scan displays?

Random scan is a method in which the display is made by theelectronic beam which is directed only to the points or part of thescreen where the picture is to be drawn.

The Raster scan system is a scanning technique in which theelectrons sweep from top to bottom and from left to right. Theintensity is turned on or off to light and unlight the pixel.

UNIT III1. State the properties of Holographic images?Holographic images are

not clear diagrams 3-dimensional

P a g e | 3

8/2/2019 2marks_CG

4/8


can also be recorded on materials other than photographic plates records intensity of light and phase created by coherent light using a laser beam

2. Define Fractals?Fractals are regular objects with a high degree of irregular shapes. Itis a lossy compression technique but it doesnt change the shape of the image. Fractals are decompressed images that result from acompression format

3. Explain Fractal Compression?Fractal Compression is based on image content i.e., it is based onsimilarity of patterns within an image. The steps in Fractalcompression are

a digitized image is broken into segments

the individual segments are checked against a library of fractals the library contains a compact set of numbers called iteratedfunction system codes. these system codes will reproduce thecorresponding fractal

4. State the applications of Document Imaging?Document Imaging is used in organizations such as

Insurance agencies Law offices Country and State Governments Federal Government Department of Defence (DOD)

Define Compression Efficiency?Compression Efficiency is defined as the ratio in bytes of anuncompressed image to the same image after compression.

5. What is Image Processing?Image Processing refers to processing a digital image using a digitalcomputer. An image processing system will alter the contents of theimage. It involves Image Recognition, Image Enhancement, ImageSynthesis and Image Reconstruction.

6. Explain Image Calibration? The overall image density is calibrated. In Image calibration the imagepixels are adjusted to a predefined level.

7. What is Grayscale Normalization? The overall grayscale of an image or picture is evaluated to determine if it is skewed in one direction and if it needs correction.8. What is Frame Averaging?

The intensity level of the frame is averaged to overcome the effects of very dark or very light areas by adjusting the middle tones.9. What is Image Animation?

Images are displayed sequentially at controlled display speeds toprovide image animation. Image Animation is the basic concept of displaying successive images at short intervals to give the perceptionof motion. Image Animation is a technology developed by Walt Disneyand brought to every home in the form of cartoons.

P a g e | 4

8/2/2019 2marks_CG

5/8


10. How Image Annotation is done?Image Annotation can be performed in two ways

as a text file stored along the image. as a small image stored with the original image.

11. State the resolution of Facsimile, Document Images andPhotographic Images? Facsimile 100 to 200 dpi Document images 300 dpi (dots/pixels per inch) Photographic images 600 dpi

12. What is the compression technique used in Facsimile andDocument Images? Facsimile - CCITT Group3 Document Images - CCITT Group4

13. What are the applications of Photographic Images?

Photographic images are used in Imaging Systems that are used foridentification such as Security Badges Fingerprint Cards Photo Identification Systems

UNIT IV

1. Define collaborative computing environment? The recent infrastructure of networked workstations and pcs, and theavailability of audio and video at these end points, makes it easier topeople to cooperate and bridge space and time. In this way, networkconnectivity and endpoint integration of multimedia provide userswith a collaborative computing environment. It is generally known ascomputer supported cooperative work (CSCW).2. List out the tools for collaborative computing

The tools used for collaborative computing are as follows: Electronic mail Bulletin boards(e.g. Usenet news) Screen sharing tools(e.g. show me from sunsoft)

Text-based conferencing systems (e.g. Internet relay chat,CompuServe,America online). Telephone conference systems. Conference rooms(e.g. video window from Bellcore) Video conference systems(e.g.,Mbone tools)3. What is group communication (GC)?Group communication (GC) involves the communication of multipleusers in a synchronous or an asynchronous mode with centralized ordistributed control.4. What are the consistent of a group communication?Group communication architecture consists of the following: Support model System model Interface model

P a g e | 5

8/2/2019 2marks_CG

6/8


The GC support model includes group communication agents thatcommunicate via a multi-point multi-cast communication network.

5. Define the term Group Rendezvous?Group rendezvous denotes a method, which allows one to organizemeetings and to get information about the group, ongoing meetingsand other static and dynamic information.6. List out some examples for interface model protocols.Synchronous rendezvous methods use: Directory services Explicit invitationsDirectory services access information stored in a knowledge baseabout the conference, such as the name of the conference,registered participants, authorized users and name and role of theparticipants.7. What are the advantages and disadvantages of replicated

architecture? The advantages of replicated architecture are: Low network traffic Low response timesLow network traffic is because only input events are distributoramong the sites and low response times, since all participants gettheir output from local copies of the application. The disadvantagesare the requirement of the same execution environment for theapplication of each site, and the difficulty in maintaining consistency.8. What are the advantages and disadvantages of

centralized conference control? The advantage of the centralized conference control is guaranteedconsistency of the conference state. The disadvantage is that when anew participant (outside of the invited group) wants to join, explicitexchange of the conference state must be performed among allparticipants, which causes large delays.9. What are the advantages of distributed conference

control?Advantages of distributed conference control are: Inherent fault tolerance-If a network connection breaks down in themiddle of a conference and it is repaired, it is easier to re-establishthe shared conference state since there is no strict consistencyrequirement. Scaling properties-At some point refresh periodicity needs to adaptto the size and scope of the conference, otherwise, the conferencemay be in danger of flooding itself with session reports.10. What is a session manager?

Session management architecture is built around an entity sessionmanager, which separates the control from the transport. By creatinga reusable session manager, which is separated from the userinterface, conference oriented tools avoid a duplication of their effort.

P a g e | 6

8/2/2019 2marks_CG

7/8


11. List the various functionalities of session managerSession manager includes local and remote functionalities. Localfunctionalities include: Membership control management Floor control Media control management Configuration management Conference control management12. What are the contents of synchronization ?Synchronization in multimedia systems comprises of content, spatialandtemporal relations between media objects.13. What is presentation requirement?Presentation requirements consist of intra-object synchronization, theaccuracy concerning delays in the presentation of LDUs and, forinter-object synchronization, the accuracy in the parallel presentationof media objects.

UNIT V1. State the applications of Non-Textual Image Recognition? Recognition of human faces Interpretation of facial expressions Designing, Manufacturing and Medical fields Security systems2. What is Hypermedia?

The linking of media for easy access is called Hypermedia. The media

may be of any type such as text, audio, video etc. A hypermediadocument contains a text and any other sub objects such as images,sound, full-motion video etc

3. What is Hypertext? The linking of associated data for easy access is called Hypertext. It isan application of indexing text to provide a rapid search of specifictext strings in one or more documents. It is an integral component of Hypermedia. Hypermedia document is the basic object and text is asub object.

4. What is multimedia PC:

A multimedia PC is a computer that has a CD-ROM or DVD drive andsupports 8-bit and 16-bit waveform audio recording and playback,MIDI soundsynthesis, and MPEG movie watching, with a centralprocessor fast enough and aRAM large enough to enable the user toplay and interact with these media in real time, and with a hard disklarge enough to store multimedia works that the user can create.

5. Where to use multimedia?Multimedia improves information relation. Multimedia applicationsincludes the following:BusinessSchoolsHome 6. What is meant by Multimedia User Interface?

P a g e | 7

8/2/2019 2marks_CG

8/8


Multimedia user interface is a computer interface that communicateswith users multiple media.

BIG QUESTIONS

1. Explain about general three dimensional rotation.2. Discuss in detail about basic 3D transformations3. Explain about projections.4. Explain the depth buffer method of visible surface detection

method.5. Explain about scan-line method6. explain briefly about depth sorting method.

7. Explain about area-subdivision method.8. What is color model?9. Define hue, saturation and value.10. Explain XYZ color model.11. Explain RGB color model.12. Explain YIQ color model.13. Explain CMY color model.14. Explain HSV color model.15. Give the procedure to conv ert HSV & RGB color model.What are called halftones?

16. Explain 2d Rotation17. Explain 2D Translation18. Explain 2D Scaling19. Explain Line Clipping20. Explain Polygon Clipping21. Write notes on Images on Web22. Explain about Still Images23. Discuss on Digital Imaging24. Writ note on Picture Construction Techniques25. Explain Illustrated Images and Tex26. Write note on Presentation requirements27. Explain presentation Function28. Explain presentation Architecture29. write note on Illustrated Zooming.

----------------*********** ALL THE BEST ***********-------------

P a g e | 8

2marks_cg

Documents