Chapter 1 - Data Storage, part b

General Outcomes

This chapter is "long." So to make it more manageable, we have divided into two sections and test over them separately.
  • Apply an understanding of how computers represent various kinds of values to a variety of situations in both a CS classroom and daily life, e.g.,
    • Explain bits and bytes and how they are organized.
    • Explain how the same sequence of bits can be interpreted as different types of data (numbers, images, sound, text, etc.)
    • Explain standard encodings for various forms of "media" (text, images, and sound).
    • Estimate storage requirements for various forms of "media" based on size needed for representation and elements being represented (e.g., bits needed for individual values and the number of values needed).
    • Explain surprising or incorrect results from computer programs.
    • Discuss situations where inexactness of computer calculations matter and don't matter explaining the source of the inexactness.

  • Recognize that computers are not infallible—that errors can occur and can, in some cases, be recognized and corrected.

 

Learning Outcomes

By the end of this unit students should be able to:

  • Explain overflow errors.
  • Explain truncation (round-off) errors.
  • Discuss situations where inexactness of computer calculations matter (and situations where it doesn't matter) explaining the source of the inexactness.
  • Explain how a photo is encoded in [24 | 32] bit format.
  • Calculate the size in memory of an uncompressed photo in [24|32]-bit format.
  • Explain how a sound file is encoded.
  • Calculate the size in memory of an uncompressed sound file.
  • Explain how a text file is encoded in [ASCII | UNICODE] format.
  • Calculate the size in memory of an uncompressed text file in [ASCII | UNICODE] format.
  • Define [Lossy | Lossless] compression.
  • Explain the difference between Lossy/Lossless compression.
  • Give an example of a Lossy Compression technique and how it works.
  • Give an example of a Lossless Compression technique and how it works.
  • Given a description of a compression technique, explain if it is lossy or lossless.
  • Explain communication errors.
  • Explain how parity bits can be used to detect communication errors.
  • Explain the difference between error detection and error correction.