1.2.4 Data Storage

Question 1

ASCII Character Set.

Answer 1

• 7 bits per character
• 128 max characters
• represents English

Question 2

Advantage of ASCII.

Answer 2

• takes up less space as it only has 128 characters

Question 3

Disadvantage of ASCII.

Answer 3

• limited amount of characters can be held

Question 4

Extended ASCII Character Set.

Answer 4

• 8 bits per character
• 256 max characters
• represents English

Question 5

What is included with Metadata?

Answer 5

Location
Date
Width
Height
Colour Depth

Question 6

How do you calculate file size of an image?

Answer 6

Height x Width x Colour Depth

Question 7

What is Sample Rate?

Answer 7

How many samples are recorded per second.

Question 8

What is Bit Depth?

Answer 8

Amount of information stored with each sample.

Question 9

How do you calculate Bit Rate?

Answer 9

Sample rate x Bit Depth x No. of Channels (1/2/3 bit etc.)

Question 10

How do you calculate file size of a sample?

Answer 10

Bit Depth x Duration

Question 11

Lossy Compression.

Answer 11

Original data can be disregarded (permanently), so less data needs to be stored.
File size decreases massively.
Doesn’t work on written documents.
Works on music, images, videos.

Question 12

Lossless Compression.

Answer 12

Reduces file sizes by using patterns.
No loss of quality.
Less effective at reducing file sizes.
Reversible.
Works on audio, images, text documents.