AP CSP - Data Compression

Front

A student is recording a song on her computer. When the recording is finished, she saves a copy on her computer. The student notices that the saved copy is of lower sound quality than the original recording. Which of the following could be a possible explanation for the difference in sound quality? Options: The song was saved using fewer bits per second than the original song., The song was saved using more bits per second than the original song., The song was saved using a lossless compression technique., Some information is lost every time a file is saved from one location on a computer to another location.

Back

The song was saved using fewer bits per second than the original song.

Front

What is abstraction?

Back

Hiding the complexity with something simpler

Front

When visiting a museum Sue takes a photo of a painting with a smartphone which stores the photo as an image file. Which of the following best describes the differences between the painting itself and the photo of the painting stored on the smartphone?

Back

The photo is a digital representation of the analog painting

Front

Ryan is designing an app that needs to quickly send low quality photos between users. Most smartphones take much higher quality photos than Ryan needs for his app. Which answer best describes the type of compression Ryan should choose and why?

Back

Lossy compression since it typically results in smaller data sizes.

Front

What is the process called when converting analog data into digital?

Back

Sampling

Front

Which of the following is a reason to use lossy compression? You want the compressed file to be larger than the original. You want the highest quality audio file possible, with no modifications. You want the highest quality image file possible, with no modifications. You want to save space and are not concerned if the file is the highest quality possible.

Back

You want to save space and are not concerned if the file is the highest quality possible.

Front

Which of the file types is an audiofile type? Options: jpg, mp3, png, csv

Back

mp3

Front

An original file is 100 MB, it is compressed to 80 MB (including dictionary). What is its compression rate?

Back

20%

Front

Values that change smoothly, rather than in discrete intervals, over time. For example, the pitch and volume of a live concert.

Back

analog data

Front

Compressing data in a way that discards some data and makes it impossible to recover the original.

Back

lossy