Digital Electronic MCQ Set 1
1. To convert a continuous sensed data into Digital form, which of the following is required?
a) Sampling
b) Quantization
c) Both Sampling and Quantization
d) Neither Sampling nor Quantization
Answer
Answer: c [Reason:] The output of the most sensor is a continuous waveform and the amplitude and spatial behavior of such waveform are related to the physical phenomenon being sensed.
2. To convert a continuous image f(x, y) to digital form, we have to sample the function in ____
a) Coordinates
b) Amplitude`
c) All of the mentioned
d) None of the mentioned
Answer
Answer: c [Reason:] An image may be continuous in the x- and y-coordinates or in amplitude, or in both.
3. For a continuous image f(x, y), how could be Sampling defined?
a) Digitizing the coordinate values
b) Digitizing the amplitude values
c) All of the mentioned
d) None of the mentioned
Answer
Answer: a [Reason:] Sampling is the method of digitizing the coordinate values of the image.
4. For a continuous image f(x, y), Quantization is defined as
a) Digitizing the coordinate values
b) Digitizing the amplitude values
c) All of the mentioned
d) None of the mentioned
Answer
Answer: b [Reason:] Sampling is the method of digitizing the amplitude values of the image.
5. Validate the statement:
“For a given image in one-dimension given by function f(x, y), to sample the function we take equally spaced samples, superimposed on the function, along a horizontal line. However, the sample values still span (vertically) a continuous range of gray-level values. So, to convert the given function into a digital function, the gray-level values must be divided into various discrete levels.”
a) True
b) False
Answer
Answer: a [Reason:] Digital function requires both sampling and quantization of the one-dimensional image function.
6. How is sampling been done when an image is generated by a single sensing element combined with mechanical motion?
a) The number of sensors in the strip defines the sampling limitations in one direction and Mechanical motion in the other direction.
b) The number of sensors in the sensing array establishes the limits of sampling in both directions.
c) The number of mechanical increments when the sensor is activated to collect data.
d) None of the mentioned.
Answer
Answer: c [Reason:] When an image is generated by a single sensing element along with mechanical motion, the output data is quantized by dividing the gray-level scale into many discrete levels. However, sampling is done by selecting the number of individual mechanical increments recorded at which we activate the sensor to collect data.
7. How does sampling gets accomplished with a sensing strip being used for image acquisition?
a) The number of sensors in the strip establishes the sampling limitations in one image direction and Mechanical motion in the other direction
b) The number of sensors in the sensing array establishes the limits of sampling in both directions
c) The number of mechanical increments when the sensor is activated to collect data
d) None of the mentioned
Answer
Answer: a [Reason:] When a sensing strip is used the number of sensors in the strip defines the sampling limitations in one direction and mechanical motion in the other direction.
8. How is sampling accomplished when a sensing array is used for image acquisition?
a) The number of sensors in the strip establishes the sampling limitations in one image direction and Mechanical motion in the other direction
b) The number of sensors in the sensing array defines the limits of sampling in both directions
c) The number of mechanical increments at which we activate the sensor to collect data
d) None of the mentioned
Answer
Answer: b [Reason:] When we use sensing array for image acquisition, there is no motion and so, only the number of sensors in the array defines the limits of sampling in both directions and the output of the sensor is quantized by dividing the gray-level scale into many discrete levels.
9. The quality of a digital image is well determined by _____
a) The number of samples
b) The discrete gray levels
c) All of the mentioned
d) None of the mentioned
Answer
Answer: c [Reason:] The quality of a digital image is determined mostly by the number of samples and discrete gray levels used in sampling and quantization.
Digital Electronic MCQ Set 2
1. Smoothing filter is used for which of the following work(s)?
a) Blurring
b) Noise reduction
c) All of the mentioned
d) None of the mentioned
Answer
Answer: c [Reason:] Smoothing filter is used for blurring and noise reduction.
2. The response of the smoothing linear spatial filter is/are ____
a) Sum of image pixel in the neighborhood filter mask
b) Difference of image in the neighborhood filter mask
c) Product of pixel in the neighborhood filter mask
d) Average of pixels in the neighborhood of filter mask
Answer
Answer: d [Reason:] The average of pixels in the neighborhood of filter mask is simply the output of the smoothing linear spatial filter.
3. Which of the following filter(s) results in a value as average of pixels in the neighborhood of filter mask.
a) Smoothing linear spatial filter
b) Averaging filter
c) Lowpass filter
d) All of the mentioned
Answer
Answer: d [Reason:] The output as an average of pixels in the neighborhood of filter mask is simply the output of the smoothing linear spatial filter also known as averaging filter and lowpass filter.
4. What is/are the resultant image of a smoothing filter?
a) Image with high sharp transitions in gray levels
b) Image with reduced sharp transitions in gray levels
c) All of the mentioned
d) None of the mentioned
Answer
Answer: b [Reason:] Random noise has sharp transitions in gray levels and smoothing filters does noise reduction.
5. At which of the following scenarios averaging filters is/are used?
a) In the reduction of irrelevant details in an image
b) For smoothing of false contours
c) For noise reductions
d) All of the mentioned
Answer
Answer: d [Reason:] Averaging filter or smoothing linear spatial filter is used: for noise reduction by reducing the sharp transitions in gray level, for smoothing false contours that arises because of use of insufficient number of gray values and for reduction of irrelevant data i.e. the pixels regions that are small in comparison of filter mask.
6. A spatial averaging filter having all the coefficients equal is termed ___
a) A box filter
b) A weighted average filter
c) A standard average filter
d) A median filter
Answer
Answer: a [Reason:] An averaging filter is termed as box filter if all the coefficients of spatial averaging filter are equal.
7. What does using a mask having central coefficient maximum and then the coefficients reducing as a function of increasing distance from origin results?
a) It results in increasing blurring in smoothing process
b) It results to reduce blurring in smoothing process
c) Nothing with blurring occurs as mask coefficient relation has no effect on smoothing process
d) None of the mentioned
Answer
Answer: a [Reason:] Use of a mask having central coefficient maximum and then the coefficients reducing as a function of increasing distance from origin is a strategy to reduce blurring in smoothing process.
8. What is the relation between blurring effect with change in filter size?
a) Blurring increases with decrease of the size of filter size
b) Blurring decrease with decrease of the size of filter size
c) Blurring decrease with increase of the size of filter size
d) Blurring increases with increase of the size of filter size
Answer
Answer: d [Reason:] Using a size 3 filter 3*3 and 5*5 size squares and other objects shows a significant blurring with respect to object of larger size.
The blurring gets more pronounced while using filter size 5, 9 and so on.
Digital Electronic MCQ Set 3
1. The length of a boundary is one of the boundary descriptors.
a) True
b) False
Answer
Answer: a [Reason:] The length of a boundary is one of the simple boundary descriptor. The length of the boundary is approximately given by the number of pixels along that boundary.
2. Which of the following of a boundary is defined as the line perpendicular to the major axis?
a) Equilateral axis
b) Equidistant axis
c) Minor axis
d) Median axis
Answer
Answer: c [Reason:] The minor axis of a boundary is defined as the line perpendicular to the major axis and of such length that a box passing through the outer four points of intersection of the boundary with the two axes completely encloses the boundary.
3. Which of the following is the useful descriptor of a boundary, whose value is given by the ratio of length of the major axis to the minor axis?
a) Radius
b) Perimeter
c) Area
d) Eccentricity
Answer
Answer: d [Reason:] Eccentricity, which is the ratio of major axis to the minor axis which is one of the important parameter that is used to describe a boundary.
4. The term, Curvature is defined as:
a) Rate of change of area
b) Rate of change of slope
c) Slope
d) Rate of change of diameter
Answer
Answer: b [Reason:] Curvature of a boundary is defined as the rate of change of slope. In general, as the boundaries tend to be locally ragged, it is difficult to obtain reliable measures of curvature at a point on a digital boundary.
5. If the boundary is traversed in the clockwise direction, a vertex point ‘p’ is said to be a part of the convex segment if the rate of change of slope at ‘p’ is:
a) Negative
b) Zero
c) Non negative
d) Cannot be determined
Answer
Answer: c [Reason:] If the boundary is traversed in the clockwise direction and the rate of change of slope at the vertex point is non negative, then that point is said to be in the convex segment.
6. A point ‘p’ is said to be corner point, if the change of slope is less than 100.
a) True
b) False
Answer
Answer: b [Reason:] In general, a point ‘p’ is said to be on the straight line segment if the change of slope is less than 100 and said to be at the corner point if the change exceeds 900.
7. Based on the 4-directional code, the first difference of smallest magnitude is called as:
a) Shape number
b) Chain number
c) Difference
d) Difference number
Answer
Answer: a [Reason:] We know that, the first difference of a chain coded boundary depends on the starting point. Based on such 4 directional boundary, the first difference of smallest magnitude is called as the shape number of the boundary.
8. The order of shape number for a closed boundary is:
a) Odd
b) Even
c) 1
d) Any positive value
Answer
Answer: b [Reason:] The order of shape number gives the number of digits in its representation. The value of this order is even for closed boundary and limits the number of possible different shapes.
9. What is the order of the shape number of a rectangular boundary with the dimensions of 3×3?
a) 3
b) 6
c) 9
d) 12
Answer
Answer: d [Reason:] The order of shape number is also defined as the perimeter of the boundary. Since, given is a rectangle of dimensions 3×3, the perimeter of the rectangle is given as 2(3+3) = 12.
10. The chain code for the following shape is given as:
a) 000030032232221211
b) 003010203310321032
c) 022332103210201330
d) 012302301023100321
Answer
Answer: a [Reason:] The effective boundary for the given figure is given as
So, the chain code is given as 000030032232221211.
11. What is the shape number for the boundary given in the previous figure?
a) 003231023101230123
b) 012301220331023010
c) 133021030012330120
d) 000310330130031303
Answer
Answer: d [Reason:] The chain code for the boundary is given as 000030032232221211.
We know that, shape number is the first difference of a chain coded boundary. Thus the shape number of the above given boundary will be 000310330130031303.
12. Statistical moments are used to describe the shape of boundary segments quantitatively.
a) True
b) False
Answer
Answer: a [Reason:] Statistical moments like mean, variance and higher order moments can quantitatively describe the shape of boundary segments.
13. Which of the following techniques of boundary descriptions have the physical interpretation of boundary shape?
a) Fourier transform
b) Statistical moments
c) Laplace transform
d) Curvature
Answer
Answer: b [Reason:] The statistical moments have an advantage over the other techniques that it helps in the physical interpretation of the shape of the boundary.
14. Statistical moments is sensitive to rotation.
a) True
b) False
Answer
Answer: b [Reason:] The statistical moment technique of describing the shape of boundary is insensitive of the rotation of the shape. If desired, size normalization can be achieved by scaling the range of values of ‘g’ and ‘r’.
Digital Electronic MCQ Set 4
1. Which of the following fact is true for a image?
a) An image is the addition of illumination and reflectance component
b) An image is the subtraction of illumination component from reflectance component
c) An image is the subtraction of reflectance component from illumination component
d) An image is the multiplication of illumination and reflectance component
Answer
Answer: d [Reason:] An image is expressed as the multiplication of illumination and reflectance component.
2. If an image is expressed as the multiplication of illumination and reflectance component i.e. f(x, y)= i(x, y) * r(x, y), then Validate the statement “We can directly use the equation f(x, y)= i(x, y) * r(x, y) to operate separately on the frequency component of illumination and reflectance” .
a) True
b) False
Answer
Answer: b [Reason:] For an image is expressed as the multiplication of illumination and reflectance component i.e. f(x, y)= i(x, y) * r(x, y), the equation can’t be used directly to operate separately on the frequency component of illumination and reflectance because the Fourier transform of the product of two function is not separable.
3. In Homomorphic filtering which of the following operations is used to convert input image to discrete Fourier transformed function?
a) Logarithmic operation
b) Exponential operation
c) Negative transformation
d) None of the mentioned
Answer
Answer: a [Reason:] For an image is expressed as the multiplication of illumination and reflectance component i.e. f(x, y) = i(x, y) * r(x, y), the equation can’t be used directly to operate separately on the frequency component of illumination and reflectance because the Fourier transform of the product of two function is not separable. So, the logarithmic operation is used.I{z(x,y)}=I{ln(f(x,y)) }=I{ln(i(x,y)) }+I{ln(r(x,y))}.
4. A class of system that achieves the separation of illumination and reflectance component of an image is termed as ____
a) Base class system
b) Homomorphic system
c) Base separation system
d) All of the mentioned
Answer
Answer: b [Reason:] Homomorphic system is a class of system that achieves the separation of illumination and reflectance component of an image.
5. Which of the following image component is characterized by a slow spatial variation?
a) Illumination component
b) Reflectance component
c) All of the mentioned
d) None of the mentioned
Answer
Answer: a [Reason:] The illumination component of an image is characterized by a slow spatial variation.
6. Which of the following image component varies abruptly particularly at the junction of dissimilar objects?
a) Illumination component
b) Reflectance component
c) All of the mentioned
d) None of the mentioned
Answer
Answer: b [Reason:] The reflectance component of an image varies abruptly particularly at the junction of dissimilar objects.
7. The reflectance component of an image varies abruptly particularly at the junction of dissimilar objects. The characteristic lead to associate illumination with ____
a) The low frequency of Fourier transform of logarithm of the image
b) The high frequency of Fourier transform of logarithm of the image
c) All of the mentioned
d) None of the mentioned
Answer
Answer: b [Reason:] The reflectance component of an image varies abruptly, so, is associated with the high frequency of Fourier transform of logarithm of the image.
8. The illumination component of an image is characterized by a slow spatial variation. The characteristic lead to associate illumination with ____
a) The low frequency of Fourier transform of logarithm of the image
b) The high frequency of Fourier transform of logarithm of the image
c) All of the mentioned
d) None of the mentioned
Answer
Answer: a [Reason:] The illumination component of an image is characterized by a slow spatial variation, so, is associated with the low frequency of Fourier transform of logarithm of the image.
9. If the contribution made by illumination component of image is decreased and the contribution of reflectance component is amplified, what will be the net result?
a) Dynamic range compression
b) Contrast enhancement
c) All of the mentioned
d) None of the mentioned
Answer
Answer: c [Reason:] The illumination component of an image is characterized by a slow spatial variation and the reflectance component of an image varies abruptly particularly at the junction of dissimilar objects, so, if the contribution made by illumination component of image is decreased and the contribution of reflectance component is amplified then there is simultaneous dynamic range compression and contrast stretching.
Digital Electronic MCQ Set 5
1. Color model is also named as (another name):
a) Color space
b) Color gap
c) Color space & color system
d) Color system
Answer
Answer: c [Reason:] A color model is also called as color space or color system .Its purpose is to facilitate the specification of colors in some standard, generally accepted way.
2. What do you mean by the term pixel depth?
a) It is the number of bits used to represent each pixel in RGB space
b) It is the number of bytes used to represent each pixel in RGB space
c) It is the number of units used to represent each pixel in RGB space
d) It is the number of mm used to represent each pixel in RGB space
Answer
Answer: a [Reason:] Images are represented in the RGB color model consist of three component images one for each primary color. When fed into RGB monitor, these three images combine on the phosphor screen to produce a composite color image. The number of bits used to represent each pixel in RGB space is called the pixel depth.
3. How many bit RGB color image is represented by full-color image?
a) 32-bit RGB color image
b) 24-bit RGB color image
c) 16-bit RGB color image
d) 8-bit RGB color image
Answer
Answer: b [Reason:] The term full-color image is used often to denote a 24-bit RGB color image. The total number of colors in a 24-bit RGB color image is (28)3=16777216.
4. What is the equation used to obtain S component of each RGB pixel in RGB color format?
a) S=1+3/(R+G+B) [min(R,G,B)].
b) S=1+3/(R+G+B) [max(R,G,B)].
c) S=1-3/(R+G+B) [max(R,G,B)].
d) S=1-3/(R+G+B) [min(R,G,B)].
Answer
Answer: d [Reason:] If an image is given in RGB format then the saturation component is obtained by the equation.
5. What is the equation used to obtain I(Intensity) component of each RGB pixel in RGB color format?
a) I=1/2(R+G+B)
b) I=1/3(R+G+B)
c) I=1/3(R-G-B)
d) I=1/3(R-G+B)
Answer
Answer: b [Reason:] If an image is given in RGB format then the intensity (I) component is obtained by the equation, I=1/3 (R+G+B).
6. What is the equation used for obtaining R value in terms of HSI components?
a) R=I[1-(S cosH)/cos(60°-H) ].
b) R=I[1+(S cosH)/cos(120°-H)].
c) R=I[1+(S cosH)/cos(60°-H) ].
d) R=I[1+(S cosH)/cos(30°-H) ].
Answer
Answer: c [Reason:] Given values of HSI in the interval [0, 1], the R value in the RGB components is given by the equation:
7. What is the equation used for calculating B value in terms of HSI components?
a) B=I(1+S)
b) B=S(1-I)
c) B=S(1+I)
d) B=I(1-S)
Answer
Answer: d [Reason:] Given values of HSI in the interval [0, 1], the B value in the RGB components is given by the equation: B=I(1-S).
8. What is the equation used for calculating G value in terms of HSI components?
a) G=3I-(R+B)
b) G=3I+(R+B)
c) G=3I-(R-B)
d) G=2I-(R+B)
Answer
Answer: a [Reason:] Given values of HSI in the interval [0, 1], the B value in the RGB components is given by the equation: G=3I-(R+B).
9. Which of the following color models are used for color printing?
a) RGB
b) CMY
c) CMYK
d) CMY and CMYK
Answer
Answer: d [Reason:] The hardware oriented models which are prominently used in the color printing process are CMY (cyan, magenta and yellow) and CMYK (cyan, magenta, yellow and black).
