Digital Image Processing Multiple Choice Questions & Answers on “Basics Of Image Sampling & Quantization”.
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: C
Clarification: 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: C
Clarification: 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: A
Clarification: 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: B
Clarification: 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: A
Clarification: 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: C
Clarification: 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: A
Clarification: 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: B
Clarification: 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: C
Clarification: The quality of a digital image is determined mostly by the number of samples and discrete gray levels used in sampling and quantization.