by DeepWebLabs
GATE-GE SERIES
Geo-informatics-engineering

Digital Image Processing

12 previous year questions.

Volume: 12 Ques
Yield: Medium

High-Yield Trend

5
2025
7
2023

Chapter Questions
12 MCQs

01
PYQ 2023
medium
geo-informatics-engineering ID: gate-ge-

In the grid below, the four corners A, B, C and D are the pixel locations on an image. The brightness values at pixels A, B, C and D are 10, 20, 5 and 30, respectively. Using bilinear interpolation, the brightness value determined at point P is ................. (Rounded off to 1 decimal place).

1
20.3
2
20.2
3
20.1
4
20.5
02
PYQ 2023
medium
geo-informatics-engineering ID: gate-ge-
The variance–covariance matrix for a 3-band image is given below (bands in the order 1, 2, 3). Which of the statement(s) is/are CORRECT?
1
The standard deviation of all bands is the same
2
The bands 1 and 2 are positively correlated
3
The bands 2 and 3 are positively correlated
4
A line fitted to the scattergram between band 1 and band 3 will have a positive slope
03
PYQ 2023
medium
geo-informatics-engineering ID: gate-ge-

The value at the center pixel of the image at (1) obtained after applying the filter given at (2) is ..................

1
70
2
68
3
69
4
71
04
PYQ 2023
medium
geo-informatics-engineering ID: gate-ge-
Which of the following statement(s) is/are TRUE regarding color theory:
1
Subtractive color theory is used for color printing
2
Additive color theory is used to display images on a color television screen
3
White light projected on a translucent filter made of yellow dye would subtract the blue light
4
White light projected on a translucent filter made of cyan dye would subtract the green light
05
PYQ 2023
medium
geo-informatics-engineering ID: gate-ge-
Which of the following statement(s) is/are CORRECT in the context of image enhancement?
1
Histogram equalization carries out a contrast stretch such that output values are displayed on the basis of their frequency of occurrence
2
Compared to a linear contrast stretch, histogram equalization is computationally more expensive
3
Both histogram equalization and linear contrast stretch are neighborhood operators
4
Histogram equalization and linear contrast stretch will produce identical results if the histogram of the input image is uniform
06
PYQ 2023
medium
geo-informatics-engineering ID: gate-ge-
Pixel indicates a pixel at location in the image coordinate system. Which of the following statement(s) is/are CORRECT?
1
Pixels and are the adjacent horizontal and vertical neighbors of pixel , respectively
2
The digital number at pixel will always be the average of the digital numbers of pixels and
3
Pixel is not an adjacent neighbor of pixel
4
Pixel has only four diagonal adjacent neighbors
07
PYQ 2023
medium
geo-informatics-engineering ID: gate-ge-
Which one of the following is NOT a linear operation?
1
Convolution
2
Moving average
3
Filtering with a median filter
4
Similarity transformation
08
PYQ 2025
medium
geo-informatics-engineering ID: gate-ge-

The error matrix resulting from randomly selected test pixels for a classified image is given below. The Producer’s accuracy of class 1 is __________ % (rounded off to 1 decimal place).

Reference Data
Class 1Class 2Class 3Class 4
Classified DataClass 1320873
Class 21227062
Class 3964105
Class 41423350

09
PYQ 2025
medium
geo-informatics-engineering ID: gate-ge-

The brightness values of four pixels in the input image are shown in the table below. The image is rectified using nearest neighbor intensity interpolation, and the pixel at location in the output image is to be filled with the value from coordinate in the input image. The brightness value of the pixel at location in the rectified output image is __________ (Answer in integer).

Location of pixels in input image
(Row, Column)		Brightness Value
(5, 3)9
(5, 4)11
(6, 3)14
(6, 4)12

10
PYQ 2025
medium
geo-informatics-engineering ID: gate-ge-

The error matrix resulting from randomly selected test pixels for a classified image is given below.
The Producer’s accuracy of class 1 is % (rounded off to 1 decimal place).

Reference Data
Class 1Class 2Class 3Class 4
Classified DataClass 1320873
Class 21227062
Class 3964105
Class 41423350
11
PYQ 2025
medium
geo-informatics-engineering ID: gate-ge-

The brightness values of four pixels in the input image are shown in the table below. The image is rectified using nearest neighbor intensity interpolation, and the pixel at location (5, 4) in the output image is to be filled with the value from coordinate (5.3, 3.7) in the input image. The brightness value of the pixel at location (5, 4) in the rectified output image is 11. (Answer in integer)

Location of pixels in input image
(Row, Column)		Brightness Value
(5, 3)9
(5, 4)11
(6, 3)14
(6, 4)12

12
PYQ 2025
medium
geo-informatics-engineering ID: gate-ge-
In case of normalized difference vegetation index (NDVI), which of the following statements is/are correct?
1
It is functionally equivalent to a simple ratio of red to near infra-red reflectance
2
It reduces many forms of multiplicative noise
3
It reduces additive noise
4
It is sensitive to canopy background variations