Face recognition concept in Computer Vision - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to load an image for face recognition.

Computer Vision

import cv2
image = cv2.imread([1])
print(image.shape)

Drag options to blanks, or click blank then click option'

Aload('face.jpg')

B'face.jpg'

Cface.jpg

Dread('face.jpg')

Attempts:

3 left

💡 Hint

Common Mistakes

Forgetting quotes around the file name

Using a function that does not exist like load() or read()

The cv2.imread function requires the file path as a string, so it must be in quotes.

2fill in blank

medium

Complete the code to convert the image to grayscale for face detection.

Computer Vision

gray_image = cv2.cvtColor(image, [1])
print(gray_image.shape)

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Acv2.COLOR_BGR2GRAY

Bcv2.COLOR_BGR2RGB

Ccv2.COLOR_RGB2GRAY

Dcv2.COLOR_GRAY2BGR

Attempts:

3 left

💡 Hint

Common Mistakes

Using RGB instead of BGR conversion codes

Converting grayscale back to color by mistake

To convert a color image to grayscale, use cv2.COLOR_BGR2GRAY.

3fill in blank

hard

Fix the error in the face detection code by filling the correct method name.

Computer Vision

face_cascade = cv2.CascadeClassifier('haarcascade_frontalface_default.xml')
facedetect = face_cascade.[1](gray_image, scaleFactor=1.1, minNeighbors=5)
print(len(facedetect))

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AdetectMultiScale

BdetectFaces

CfindFaces

Ddetect_face

Attempts:

3 left

💡 Hint

Common Mistakes

Using incorrect method names that do not exist

Confusing method names with other libraries

The correct method to detect faces using Haar cascades in OpenCV is detectMultiScale.

4fill in blank

hard

Fill both blanks to create a dictionary of face locations with width and height.

Computer Vision

faces_info = {i: (x, y, [1], [2]) for i, (x, y, w, h) in enumerate(facedetect)}
print(faces_info)

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Aw

Bh

Cx

Dy

Attempts:

3 left

💡 Hint

Common Mistakes

Using x or y instead of width and height

Mixing up the order of values

The width and height of each detected face are w and h respectively.

5fill in blank

hard

Fill all three blanks to draw rectangles around detected faces on the image.

Computer Vision

for (x, y, w, h) in facedetect:
    cv2.rectangle(image, ([1], [2]), (x + w, y + h), [3], 2)
cv2.imshow('Faces', image)
cv2.waitKey(0)
cv2.destroyAllWindows()

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Ax

By

C(255, 0, 0)

D(0, 255, 0)

Attempts:

3 left

💡 Hint

Common Mistakes

Swapping x and y coordinates

Using wrong color tuples

The rectangle starts at (x, y) and uses blue color (255, 0, 0) in BGR format.