Upwork Digital Imaging Test

1. A compandor is a

Answers:

• comparator-expander

• compressor-expander

• comparator-modulator

• compressor-demodulator

2. A CRO screen has 10 divisions on the horizontal line. If a voltage signal 5sin(314t + 45) is examined with a line base setting of 5 ms/divisions, the number of cycles in the signal displayed on the screen will be_______.

Answers:

• 0.5

• 2.5

• 5

• 10

3. A certain oscilloscope with a 4cm by 4cm screen has its sweep output fed to its input. If the x and y sensitivities are the same, the oscillosope will display a_______.

Answers:

• triangular wave

• diagonal line

• sine wave

• circle

4. Which type of vision is provided by the rods in the human eye?

Answers:

• Isotopic vision

• Orthographic vision

• Scotopic vision

• Isotropic vision

(hold on, will be updated soon)

5. In the image representation , a picture-element is also called  a _____.

Answers:

• bit

• pixel

• dit

• point

6. In which of the following image segmentation techniques are quad- trees used?

Answers:

• Feature extraction

• Segmentation

• Classification

• None of the above

7. Which of the following is a linear filtering method?

Answers:

• Wiener filter

• FIR filter

• Kalman filter

• All of the above

8. Which of the following is an image data compression technique?

Answers:

• Pixel coding

• Predictive coding

• Transform coding

• All of the above

9. Which of the following is an application of the digital image processing?

Answers:

• Geographical mapping

• Prediction of agricultural crops

• Weather forecasting

• All of the above

10. Inter-frame coding technique exploits the ______ between successive frames.

Answers:

• gaps

• redundancy

• time

• space

11. Which of the following types of photoreceptors does the retina of the human eye contain?

Answers:

• rods and cones

• cones and lens

• rods and lens

• lens and eyelid

12. In which of the following processes is the binary ladder used?

Answers:

• Analog to digital conversion

• Digital to analog conversion

• Analog to analog conversion

• Digital to digital conversion

13. To read the RMS value of which of the following waveforms are true RMS reading voltmeters used?

Answers:

• Only the sinusoidal waveform

• Only the non-sinusoidal waveform

• Both a and b

• Only the square waveform

14. White Block Skipping (WBS) is a method used for_______.

Answers:

• image filtering

• image compression

• image sampling

• image perception

15. What is the range of wavelength of the light in the visible region?

Answers:

• 150nm to 250nm

• 380nm to 750nm

• 350mm to780 mm

• 350um to 780um

16. Which of the following statements represents the Bloch's law?

Answers:

• Light flashes of different duration but equal energy are indistinguishable.

• When a slowly flashing light is observed, the individual flashes are distinguishable.

• The eye is more sensitive to the flickering of high spatial frequencies than low spatial frequencies

• All of the above

17. On how many input samples does the zero memory quantizer operate at a time?

Answers:

• One input sample

• Zero input sample

• Two input samples

• Four input samples

18. The Wiener filter can be implemented in the frequency domain via_______.

Answers:

• fast binary transform

• slow binary transform

• fast unitary transform

• slow unitary transform

19. For which of the following image data compression techniques is PCM used as a method?

Answers:

• Predictive coding

• Transform coding

• Pixel coding

• Color image coding

20. For which of following techniques is vector quantization used as a method?

Answers:

• Image perception

• Image segmentation

• Image compression

• Image sampling

21. The term digital image generally refers to the processing of a _____.

Answers:

• two-dimensional picture

• three-dimensional picture

• one-dimensional picture

• All of the above

22. Under which of the following conditions is the phenomenon called contouring used?

Answers:

• If the number of quantization levels is more than that required in gray scale quantization.

• If the number of quantization levels is less than that required in grey scale quantization.

• When there is not a single level of quantization in gray scale quantization.

• All of the above

23. Which of the following filters is used for image restoration?

Answers:

• Matched filter

• Dumb filter

• Weiner filter

• Band stop filter

24. Which of the following effects shows that brightness is not a monotonic function of luminance?

Answers:

• Background law

• Dark shadow effect

• Mach band effect

• Power band effect

25. In the structural patterns of the surfaces of which object is texture observed?

Answers:

• Wood

• Cloth

• Grain

• All of the above

26. Which of the following is an image restoration model?

Answers:

• Noise model

• Sampled observation model

• Iimage formation model

• All of the above

27. Which of the following is an advantage of the vacuum tube voltmeter over the transistorized voltmeter (TVM)?

Answers:

• The VTVM requires warm-up time

• The VTVM has high input impedance

• The power consumption of the VTVM is more in comparison with the TVM

• The VTVM cannot be operated on a low voltage source

28. Which of the following can be termed a two- tone image?

Answers:

• Line drawings

• Letters

• Newsprints

• All of the above

29. Which of the following statement is not true?

Answers:

• Any color can be matched by mixing at the most three colored lights.

• The luminance of a color mixture is equal to the sum of the luminance of its components.

• The human eye can resolve the components of a color mixture.

• A color match at one luminance level holds over a wide range of luminances.

30. To which of the following types does Weiner filtering belong?

Answers:

• Non-linear filters

• Linear filters

• Non-recursive filter

• Inverse filters

31. Contrast stretching is an_______.

Answers:

• image restoration technique

• image enhancement technique

• image analysis technique

• image segmentation technique

32. Which type of target is there in the vidicon tube?

Answers:

• Photoconductive

• Photo emissive

• Photosensitive

• All the above

33. Which of the following expressions can define the Q -factor of a coil?

Answers:

• C/R

• R/C

• L/R

• R/L

34. In the intermediate region of illumination,both rods and cones are active and provide _____.

Answers:

• photopic vision

• isotopic vision

• photographic vision

• mesopic vision

35. If two sinusoidal voltage signals, between 0 and 90 degree out of phase and of equal amplitude and equal frequencies: in a CRO are applied to the horizontal and vertical deflection plates, what shape will appear on the screen?

Answers:

• A straight line with 45 degree angle with +ve x-axis

• An ellipse

• A square

• A straight line with 135 degree angle with +ve x-axis

36. Which of the following techniques does Kalman filtering employs?

Answers:

• Least square filtering

• Fourier domain filtering

• Recursive filtering

• Interpolation filtering

37. Two objects with different surroundings can have identical _______ but different ________.

Answers:

• luminance, brightness

• brightness, luminance

• hue, brightness

• brightness, hue

38. Which of the following is a moment based feature of an image?

Answers:

• Centre of mass

• Orientation

• Bounding rectangle

• All of the above

39. Which of the following is an image segmentation technique?

Answers:

• Template matching

• Texture matching

• Boundary detection

• All of the above

40. Which of the following techniques is used in analog to digital (ADc)conversion?

Answers:

• Ramp conversion

• Dual slope conversion

• Successive- approximation conversion

• All of the above

41. Which of the following is not an image filtering method?

Answers:

• Speckle noise reduction

• Maximum entropy

• Bosch Method

• Bayesian method

42. The phenomenon in which overlapping of frequency spectrum takes place in sampling is called _______.

Answers:

• Nyquist rate

• Aliasing

• Quantization

• Digitization

43. Which of the following methods is used to analyse the structure of patterns in image analysis?

Answers:

• Medial axis transform

• Skeleton algorithms

• Thinning algorithm

• All of the above

44. Which of the following steps follows sampling in image digitization?

Answers:

• Modulation

• Filtering

• Quantization

• Demodulation

45. Which of the following filters can effectively remove the aliasing effect?

Answers:

• High pass filter

• Low pass filter

• Band pass filter

• Band stop filter

46. Of which of the following types is the general response of image detectors and recorders?

Answers:

• Non-linear

• Linear

• Exponential

• None of the above

47. Which of the following is an image analysis technique?

Answers:

• Feature extraction

• Segmentation

• Classification

• All of the above

48. About which of the following domains does image transform during image analysis provide information?

Answers:

• Frequency domain

• Time domain

• Both frequency and time domain

49. Which of the following is not a method of predictive coding?

Answers:

• Delta modulation

• Zonal coding

• Adaptive coding

• Interframe techniques

50. Which of the following is a type of digital voltmeters?

Answers:

• Ramp type

• Dual slope integrating type

• Integrating type

• All of the above