Why camera enables vision-based projects in Raspberry Pi - Test Your Understanding

Practice - 5 Tasks

1fill in blank

easy

Complete the code to capture an image using the Raspberry Pi camera.

Raspberry Pi

import picamera
with picamera.PiCamera() as camera:
    camera.[1]('image.jpg')

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

Aopen

Bstart

Crecord

Dcapture

Attempts:

3 left

💡 Hint

Common Mistakes

Using start() instead of capture()

Using open() which is not a camera method

The capture() method takes a picture with the camera.

2fill in blank

medium

Complete the code to set the resolution of the camera before capturing an image.

Raspberry Pi

import picamera
with picamera.PiCamera() as camera:
    camera.[1] = (640, 480)
    camera.capture('image.jpg')

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Aformat

Bsize

Cresolution

Dquality

Attempts:

3 left

💡 Hint

Common Mistakes

Using size instead of resolution

Using format which is for file type

The resolution property sets the width and height of the image.

3fill in blank

hard

Fix the error in the code to correctly initialize the camera and capture an image.

Raspberry Pi

import picamera
camera = picamera.PiCamera()
camera.[1]('photo.jpg')

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

Acapture

Bcapture()

Ccapture('photo.jpg')

Attempts:

3 left

💡 Hint

Common Mistakes

Not calling PiCamera() as a function

Calling capture without parentheses

You must create an instance by calling PiCamera() with parentheses, and then call capture() method with the filename.

4fill in blank

hard

Fill both blanks to create a dictionary of image filenames with their resolutions, filtering only images with width greater than 800.

Raspberry Pi

images = {'img1.jpg': (1024, 768), 'img2.jpg': (640, 480), 'img3.jpg': (1280, 720)}
filtered = {filename: res for filename, res in images.items() if res[0] [1] [2]

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A>

B<

C800

D1024

Attempts:

3 left

💡 Hint

Common Mistakes

Using < instead of >

Using 1024 instead of 800

The code filters images where the width (res[0]) is greater than 800 pixels.

5fill in blank

hard

Fill all three blanks to create a dictionary of images with width greater than 700 and height less than 800.

Raspberry Pi

images = {'a.jpg': (800, 600), 'b.jpg': (640, 480), 'c.jpg': (1024, 900)}
filtered = {filename: res for filename, res in images.items() if res[0] [1] [2] and res[1] [3] 800}

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

A>

B700

C<

D600

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing up > and <

Using wrong threshold numbers

The dictionary comprehension filters images where width is greater than 700 and height is less than 800.