1.2.5 Compression

Question 1

What is compression?

Answer 1

The process of encoding data so that it needs fewer bits/bytes to represent it.

Question 2

What are the needs of compression?

Answer 2

Takes less space when storing
Uses less bandwidth if you’re going to send it
Decompressing uses extra processing

Question 3

What is lossy compression?

Answer 3

Lossy compression compresses data files but does lose some of the information.

Question 4

What are the advantages and disadvantages of lossy compression?

Answer 4

ADVANTAGE:
Can produce smaller data files.
DISADVANTAGE:
No good if 100% accuracy required e.g. text files

Question 5

What is lossless compression?

Answer 5

Lossless compression can compress data files without losing any of the information.

Question 6

What are advantages and disadvantage of lossless compression?

Answer 6

ADVANTAGES:
Lossless compression schemes are reversible so that the original data can be reconstructed
DISADVANTAGES:
However not all data files can be compressed using lossless compression