Question 1
104.94
100.25
110.56
98.78

The IIT Madras BS Deep Learning for Computer Vision (Deep Learning for Computer Vision) Quiz 1 paper sat on 13 Jul 2025, in the May 2025 term: 34 questions for 79 marks in 120 minutes. Every question is below with its answer. Take it as a timed mock test to be marked, or read it through first.
104.94
100.25
110.56
98.78
Correct answer
104.94
Which of the following statements is false?
Histogram equalization is a global operation.
Gaussian filtering is a local operation.
Convolution in the spatial domain corresponds to multiplication in the frequency domain.
Median filtering is a global operation.
Correct answer
Median filtering is a global operation.
Which of the following statements is True?
Gaussian filter is a separable filter because it is linear.
Median filter is a non-separable filter.
Gaussian filter is a high-pass filter.
Mean filter is a non-separable filter because it is non-linear.
Correct answer
Gaussian filter is a separable filter because it is linear.
Correct answer
0.9820, 4.00, 1, 4.02, 4.00, 4.00
0.8808, 3.50, 1, 3.54, 3.50, 3.50
0.7311, 2.00, 1, 2.13, 2.00, 2.00
0.5000, 0.00, 0, 0.69, 0.00, 0.00
Correct answer
0.9820, 4.00, 1, 4.02, 4.00, 4.00
Identify the correct sequence of steps in a Canny edge detection pipeline. Steps are listed below:
Correct answer
Correct answer
During the double thresholding step in Canny edge detection, the high threshold is set at 100 and the low threshold is 40. A pixel gradient magnitude of 65 will be classified as:
Strong edge
Weak edge
Non-edge
Ambiguous edge
Correct answer
Weak edge
Match the derivative of activation functions with their counterparts on the right column accordingly.
| 1) Leaky ReLU | i) |
|---|---|
| 2) Tanh | ii) 0 if and 1 if |
| 3) ReLU | iii) |
| 4) Sigmoid | iv) 0.01 if and 1 if |
| v) 0 if and 1 if | |
| vi) 0.01 if and 1 if |
Correct answer
Correct answer
Which of the following statements are True?
Vanilla Gradient Descent converges faster than Momentum-based GD.
Momentum based GD oscillates around minima before convergence.
Noise in Stochastic Gradient descent weight updates – can lead to faster convergence.
None of these
Correct answer
Momentum based GD oscillates around minima before convergence.
0.16
0.08
0.20
0.12
Correct answer
0.16
Correct answer
Correct answer
Which of the following statements are true?(Select all that apply)
Correct answers
Which of the following statements are true ?(Select all that apply)
Correct answers
Consider the following statements. Which of the following statements are true?
Correct answers
Correct answers
Which of the following statements are false?
Momentum in optimization can cause oscillations around minima when encountering flat regions or saddle points due to the dominance of the momentum term over the small gradient.
Stochastic Gradient Descent (SGD) with its inherent noise can be beneficial in escaping local minima and saddle points, provided that there is enough gradient information in the neighborhood.
Adagrad is an optimization algorithm introduced to overcome the diminishing learning rate problem in techniques like RMSProp.
ADAM is introduced to solve problems in RMSProp by combining RMSProp and Adagrad techniques.
Correct answers
Adagrad is an optimization algorithm introduced to overcome the diminishing learning rate problem in techniques like RMSProp.
ADAM is introduced to solve problems in RMSProp by combining RMSProp and Adagrad techniques.
Consider the grayscale image shown below:
If a median filter with a neighborhood is applied to this image with a stride of 1 and no padding, __________ will be the value at position in the filtered image? (Assume that the top-left pixel coordinate of the output image is addressed as .)
Correct answer: 20
Correct answer: 4
Given a second moment matrix of edge pixels:
obtained during the Canny edge detection process, compute the measure of straightness defined as:
where and are the maximum and minimum eigenvalues of respectively.
The value of the straightness is __________
Correct answer: -2
Correct answer: 28
Correct answer: 8
Correct answer: 86400
Correct answer: -0.235 (accepted within ±0.025)
Consider the following numpy array
Now consider the following operations
Write the value of arr[0, 0]
Correct answer: 5
Consider the following numpy array
Now consider the following operations
Write the value of arr[0, 1]
Correct answer: 99
The gradient of an image I points in the direction of the most rapid change in intensity. Taking image derivatives accentuates (a)_________________ frequencies and hence amplifies noise, since the proportion of noise to signal is larger at (b) _________________frequencies. The common solution is to smooth the image prior to computing gradients.
Based on the above data, answer the given subquestions.
Enter the correct answer for Blank (a):
NOTE: Enter the exact answer without any extra space in the beginning or at the end.
Correct answer: high or higher or large or largest
The gradient of an image I points in the direction of the most rapid change in intensity. Taking image derivatives accentuates (a)_________________ frequencies and hence amplifies noise, since the proportion of noise to signal is larger at (b) _________________frequencies. The common solution is to smooth the image prior to computing gradients.
Based on the above data, answer the given subquestions.
Enter the correct answer for Blank (b):
NOTE: Enter the exact answer without any extra space in the beginning or at the end.
Correct answer: high or higher or large or largest
In Canny edge detection, a large value of the Gaussian kernel spread σ leads to (a)________________ edges, while a small value of σ leads to (b)_________________ edges.
Based on the above data, answer the given subquestions.
Enter the correct answer for Blank (a) :
NOTE: Enter the exact answer without any extra space in the beginning or at the end.
Correct answer: thick or coarse or large-scale
In Canny edge detection, a large value of the Gaussian kernel spread σ leads to (a)________________ edges, while a small value of σ leads to (b)_________________ edges.
Based on the above data, answer the given subquestions.
Enter the correct answer for Blank (b) :
NOTE: Enter the exact answer without any extra space in the beginning or at the end.
Correct answer: fine or thin
You have a visual codebook with 1500 visual words. From a test image, you extract 1200 SIFT descriptors, each of 128 dimensions. After assigning each descriptor to its nearest visual word, you compute the Bag-of-Words histogram by counting descriptor assignments.
Based on the above data, answer the given subquestions.
What is the dimensionality of the Bag-of-Words (BoW) feature vector for this
image?________________
Correct answer: 1500
You have a visual codebook with 1500 visual words. From a test image, you extract 1200 SIFT descriptors, each of 128 dimensions. After assigning each descriptor to its nearest visual word, you compute the Bag-of-Words histogram by counting descriptor assignments.
Based on the above data, answer the given subquestions.
If instead, you concatenate all the 1200 descriptors into a single vector (without using BoW), what will be the dimensionality of that vector?__________________
Correct answer: 153600