AMIETE – IT (OLD SCHEME)

 

Code: AT14                               Subject: IMAGE PROCESSING & COMPUTER GRAPHICS

Flowchart: Alternate Process: JUNE 2009Time: 3 Hours                                                                                                     Max. Marks: 100

 

 

NOTE: There are 9 Questions in all.

·      Question 1 is compulsory and carries 20 marks. Answer to Q. 1. must be written in the space provided for it in the answer book supplied and nowhere else.

·      Out of the remaining EIGHT Questions answer any FIVE Questions. Each question carries 16 marks.

·      Any required data not explicitly given, may be suitably assumed and stated.

 

 

Q.1       Choose the correct or the best alternative in the following:                                  (210)

       

             a.  The property of phosphors to continue to emit light after the CRT beam is removed is called _______________.

 

                  (A) Persistence                                     (B) Resolution

                  (C) Illuminance                                     (D) Retrace

 

             b.  Applications of this input device include virtual reality, CAD and animation.

 

                  (A) Keyboard                                      (B) Z mouse

                  (C) Digitizer                                          (D) Touch panel

 

             c.  This line drawing algorithm is a scan-conversion line algorithm based on calculating either Dy or Dx.

 

(A) Bresenham’s line algorithm             

(B) Parallel line algorithms

                  (C) Digital Differential Analyzer algorithm                                                                          

                  (D) None of the above

 

d.    The transformation matrix for a 2D reflection relative to the coordinate origin is given by

 

(A)   .                     (B)   .

(C)  .                    (D)   .

 

             e.  This projection is generated by aligning the projection plane so that it intersects each coordinate axis in which the object is defined at the same distance from the origin.

 

                  (A)  Parallel                                          (B) Oblique

                  (C)  Cavalier                                        (D) Isometric

             f.   ______________ image has a histogram that will be narrow and will be centered toward the middle of the gray scale.

 

                  (A) Bright                                             (B) Dark

                  (C) High Contrast                                 (D) Low Contrast

 

             g.  This filter is a constant function with a hole at the origin.

 

                  (A) Low pass filter                                (B) High pass filter

                  (C) Bandpass filter                                (D) Notch filter

 

             h.  The code is called ___________ as each code word in a string of code symbols can be decoded without referencing succeeding symbols.

 

                  (A) Instantaneous code                         (B) Uniquely decodable code

                  (C) Variable length code                       (D) Block code

 

             i.   The ___________ coding system of JPEG is used for progressive reconstruction applications.

 

                  (A) Lossy baseline                                (B) Extended

                  (C) Independent                                   (D) Sequential baseline

 

             j.   The ___________ of the second derivative is used to determine whether an edge pixel lies on the dark or light side of an edge.

 

                  (A) Magnitude                                      (B) Phase angle

                  (C) Sign                                               (D) Absolute value

 

 

Answer any FIVE Questions out of EIGHT Questions.

Each question carries 16 marks.

 

 

  Q.2     a.   Write short notes on

                   (i) Scanners                                         (ii) Touch panels                                     (8)

 

             b.   Explain the algorithm to generate a circle using the mid point technique.               (8)

 

  Q.3     a.   Three dimensional Tilting is defined as a rotation about the x-axis followed by a rotation about the y-axis. Find the tilting matrix. Find out whether the order of performing the rotation matters.           (8)

 

             b.   Determine the transformation matrix corresponding to a 2D reflection about (i) a horizontal line (ii) an arbitrary line.                                       (8)

 

  Q.4     a.   Clip a line with end points (0, 0) and (12, 12) using Cohen Sutherland line clipping algorithm.  The clipping rectangle diagonally opposite edges as     (-1, -1) and (10, 10).                                          (8)

 

             b.   Explain the following 3D transformations with examples.

                   (i) Translation                                      (ii) Rotation

                   (iii) Shear                                                                                                           (8)

 

  Q.5     a.   With necessary assumptions, derive the perspective matrix for perspective transformation.              (8)

 

             b.   What are visible surface detection algorithms? How are these algorithms classified? Explain the back face detection algorithm.                              (8)                                                             

 

  Q.6     a.   A common measure of transmission for digital data is the baud rate, defined as the number of bits transmitted per second. Generally, transmission is accomplished in packets consisting of a start bit, a byte (8 bits) of information, and a stop bit. (i) How many bits would it take to transmit a 1024 x 1024 image with 256 gray levels using a 56K baud modem? (ii) What would the time be at 750K baud, a representative speed of a phone DSL connection?                                                                                     (8)

 

             b.   Explain the histogram specification technique for image enhancement.                  (8)

 

  Q.7     a.   For the example image strip given, find the first derivative and second derivative. Analyze the result and find the locations of a ramp, isolated point, flat segment, thin line and step edge.

                   [5 5 4 3 2 1 0 0 0 6 0 0 0 0 1 3 1 0 0 0 0 7 7 7 7]                                             (8)

 

b.      Explain frequency domain sharpening filters. Write short notes on:

                                                                 (i) Ideal Highpass filters (ii) Butterworth Highpass filters

                                                                 (iii) Gaussian Highpass filters                                   (8)

 

  Q.8     a.   Explain the transform coding technique for still image compression with a block diagram. Provide equations for different transforms.                        (8)

 

             b.   The arithmetic decoding process is the reverse of the encoding procedure. Decode the message 0.23355 given the following coding model.         (8)

 

Symbol

Probability

A

0.2

E

0.3

I

0.1

O

0.2

U

0.1

K

0.1

                                                                                                                                                                                                                                                                                                                 

  Q.9     a.   Explain global processing via Hough Transform with necessary diagrams.            (8)

 

b.      Explain the following region based segmentation techniques:

                                                                 (i) Region growing (ii) Region splitting and merging  (8)