Intensity Transformation MCQ [Free PDF] – Objective Question Answer for Intensity Transformation Quiz

21. What is the name of the process used to correct the power-law response phenomena?

A. Beta correction
B. Alpha correction
C. Gamma correction
D. Pie correction

Answer: C

A variety of devices used for image capture, printing, and display respond according to a power law. By convention, the exponent in the power-law equation is referred to as gamma. The process used to correct these power-law response phenomena is called gamma correction.

 

22. Which of the following transformation function requires much information to be specified at the time of input?

A. Log transformation
B. Power transformation
C. Piece-wise transformation
D. Linear transformation

Answer: C

The practical implementation of some important transformations can be formulated only as piecewise functions. The principal disadvantage of piecewise functions is that their specification requires considerably more user input.

 

23. In contrast to stretching, if r1=s1 and r2=s2 then which of the following is true?

A. The transformation is not a linear function that produces no changes in gray levels
B. The transformation is a linear function that produces no changes in gray levels
C. The transformation is a linear function that produces changes in gray levels
D. The transformation is not a linear function that produces changes in gray levels

Answer: B

The locations of points (r1,s1) and (r2,s2) control the shape of the transformation function. If r1=s1 and r2=s2 then the transformation is a linear function that produces no changes in gray levels.

 

24. In contrast to stretching, if r1=r2, s1=0, and s2=L-1 then which of the following is true?

A. The transformation becomes a thresholding function that creates an octal image
B. The transformation becomes an override function that creates an octal image
C. The transformation becomes a thresholding function that creates a binary image
D. The transformation becomes a thresholding function that does not create an octal image

Answer: C

If r1=r2, s1=0 and s2=L-1,the transformation becomes a thresholding function that creates a binary image.

 

25. In contrast to stretching, if r1≤r2 and s1≤s2 then which of the following is true?

A. The transformation function is double valued and exponentially increasing
B. The transformation function is double valued and monotonically increasing
C. The transformation function is single-valued and exponentially increasing
D. The transformation function is single-valued and monotonically increasing

Answer: D

The locations of points (r1,s1) and (r2,s2) control the shape of the transformation function. If r1≤r2 and s1≤s2 then the function is single-valued and monotonically increasing.

 

26. In which type of slicing, highlighting a specific range of gray levels in an image often is desired?

A. Gray-level slicing
B. Bit-plane slicing
C. Contrast stretching
D. Byte-level slicing

Answer: A

Highlighting a specific range of gray levels in an image often is desired in gray-level slicing. Applications include enhancing features such as masses of water in satellite imagery and enhancing flaws in X-ray images.

 

27. Which of the following depicts the main functionality of the Bit-plane slicing?

A. Highlighting a specific range of gray levels in an image
B. Highlighting the contribution made to total image appearance by specific bits
C. Highlighting the contribution made to total image appearance by a specific byte
D. Highlighting the contribution made to total image appearance by specific pixels

Answer: B

Instead of highlighting gray-level ranges, highlighting the contribution made to total image appearance by specific bits might be desired. Suppose, each pixel in an image is represented by 8 bits. Imagine that the image is composed of eight 1-bit planes, ranging from bit-plane 0 for the least significant bit to bit-plane 7 for the most significant bit. In terms of 8-bit bytes, plane 0 contains all the lowest order bits in the bytes comprising the pixels in the image, and plane 7 contains all the high-order bits.

 

28. Which of the following is the primary objective of sharpening an image?

A. Blurring the image
B. Highlight fine details in the image
C. Increase the brightness of the image
D. Decrease the brightness of the image

Answer: B

The sharpening of the image helps in highlighting the fine details that are present in the image or to enhance the details that are blurred due to some reason like adding noise.

 

29. Image sharpening process is used in electronic printing.

A. True
B. False

Answer: A

The applications of image sharpening are present in various fields like electronic printing, autonomous guidance in military systems, medical imaging, and industrial inspection.

 

30. In the spatial domain, which of the following operation is done on the pixels in sharpening the image?

A. Integration
B. Average
C. Median
D. Differentiation

Answer: D

We know that, in blurring the image, we perform the average of pixels which can be considered as integration. As sharpening is the opposite process of blurring, logically we can tell that we perform differentiation on the pixels to sharpen the image.

 

31. Image differentiation enhances the edges, and discontinuities and deemphasizes the pixels with slow varying gray levels.

A. True
B. False

Answer: A

Fundamentally, the strength of the response of the derivative operative is proportional to the degree of discontinuity in the image. So, we can state that image differentiation enhances the edges, and discontinuities and deemphasizes the pixels with slow varying gray levels.

 

32. In which of the following cases, we wouldn’t worry about the behavior of the sharpening filter?

A. Flat segments
B. Step discontinuities
C. Ramp discontinuities
D. Slow varying gray values

Answer: D

We are interested in the behavior of derivatives used in sharpening in the constant gray level areas i.e., flat segments, and at the onset and end of discontinuities, i.e., step and ramp discontinuities.

 

33. Which of the following is the valid response when we apply the first derivative?

A. Non-zero at flat segments
B. Zero at the onset of gray level step
C. Zero in flat segments
D. Zero along ramps

Answer: C

The derivations of digital functions are defined in terms of differences. The definition we use for the first derivative should be zero in flat segments, nonzero at the onset of a gray level step or ramp, and nonzero along the ramps.

 

34. Which of the following is not a valid response when we apply a second derivative?

A. Zero response at the onset of gray level step
B. Nonzero response at the onset of gray level step
C. Zero response at flat segments
D. Nonzero response along the ramps

Answer: B

The derivations of digital functions are defined in terms of differences. The definition we use for the second derivative should be zero in flat segments, zero at the onset of a gray level step or ramp, and nonzero along the ramps.

 

35. If f(x,y) is an image function of two variables, then the first order derivative of a one dimensional function, f(x) is:

A. f(x+1)-f(x)
B. f(x)-f(x+1)
C. f(x-1)-f(x+1)
D. f(x)+f(x-1)

Answer: A

The first order derivative of a single dimensional function f(x) is the difference between f(x) and f(x+1).

That is, ∂f/∂x=f(x+1)-f(x).

 

36. Isolated point is also called a noise point.

A. True
B. False

Answer: A

The point which has a very high or very low gray-level value compared to its neighbors, then that point is called an isolated point or noise point. The noise point is of one-pixel size.

 

37. What is the thickness of the edges produced by first-order derivatives when compared to that of second-order derivatives?

A. Finer
B. Equal
C. Thicker
D. Independent

Answer: C

We know that the first-order derivative is nonzero along the entire ramp while the second order is zero along the ramp. So, we can conclude that the first-order derivatives produce thicker edges and the second-order derivatives produce much finer edges.

 

38. First-order derivative can enhance the fine detail in the image compared to that of a second-order derivative.

A. True
B. False

Answer: B

The response at and around the noise point is much stronger for the second-order derivative than for the first-order derivative. So, we can state that the second-order derivative is better to enhance the fine details in the image including noise when compared to that of the first-order derivative.

 

39. Which of the following derivatives produce a double response at step changes in gray level?

A. First-order derivative
B. Third-order derivative
C. Second-order derivative
D. First and second-order derivatives

Answer: C

Second-order derivatives produce a double-line response for the step changes in the gray level. We also note of second-order derivatives that, for similar changes in gray-level values in an image, their response is stronger to a line than to a step, and to a point than to a line.

 

40. The objective of sharpening spatial filters is/are to ___________

A. Highlight fine detail in an image
B. Enhance detail that has been blurred because of some error
C. Enhance detail that has been blurred because of some natural effect of some method of image acquisition
D. All of the mentioned

Answer: D

Highlighting the fine detail in an image or Enhancing detail that has been blurred because of some error or some natural effect of some method of image acquisition, is the principal objective of sharpening spatial filters.

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