Capturing still images in Raspberry Pi - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is the basic command to capture a still image using the Raspberry Pi camera module?

The basic command is raspistill -o image.jpg, which captures an image and saves it as image.jpg.

beginner

What does the -o option specify in the raspistill command?

The -o option specifies the output filename where the captured image will be saved.

intermediate

How can you add a delay before capturing an image with raspistill?

Use the -t option followed by the delay time in milliseconds. For example, raspistill -t 5000 -o image.jpg waits 5 seconds before taking the picture.

beginner

What Python library can you use to capture still images programmatically on a Raspberry Pi?

You can use the picamera Python library to control the Raspberry Pi camera and capture images in your Python scripts.

beginner

How do you capture a still image using the picamera library in Python?

Example code:<br><pre>import picamera
with picamera.PiCamera() as camera:
    camera.capture('image.jpg')</pre>This captures and saves an image named <code>image.jpg</code>.

Which command captures a still image immediately and saves it as 'photo.jpg'?

A raspistill -t 5000 -o photo.jpg

B raspivid -o photo.jpg

C raspistill -o photo.jpg

D raspivid -t 1000 -o photo.jpg

raspistill is used for still images; the -o option sets the output file.

What does the -t option do in the raspistill command?

A Sets a delay before capturing the image

B Sets the image resolution

C Specifies the output filename

D Starts video recording

The -t option sets the delay time in milliseconds before the image is taken.

Which Python library is commonly used to control the Raspberry Pi camera?

A opencv

B picamera

C pygame

D matplotlib

picamera is designed specifically for Raspberry Pi camera control.

In Python, which method captures an image using picamera?

A camera.record()

B camera.snap()

C camera.take_photo()

D camera.capture()

The capture() method takes a still image and saves it.

What file format does raspistill save images in by default?

A JPEG

B BMP

C PNG

D GIF

raspistill saves images in JPEG format by default.

Explain how to capture a still image on a Raspberry Pi using both the command line and Python.

Think about the command line tool and the Python library.

Describe the steps to add a delay before taking a picture with the Raspberry Pi camera.

The delay is set in milliseconds using a command option.