1.2 text, sound and images Flashcards
1
Q
how computer represents text
A
- text converted into binary
- to be processed by computer
- use character sets
2
Q
what is a character set
A
- collection of characters
- and corresponding binary codes that represent them
3
Q
unicode vs ascii
A
- unicode greater range of characters and symbols than ascii
- unicode require more bits per character than ascii
4
Q
how does computer represent sound
A
- sound wave sampled for sound to be converted into binary
- analogue to digital form
- which is processed by computer
5
Q
how is sound recorded
A
- amplitude of sound wave determined at set time intervals
- value converted to digital form
- each sample of sound wave encoded as binary
- series of readings gives approx representation of sound wave
6
Q
what is sample resolution
A
- number of bits per sample
7
Q
effects of sample resolution
A
- accuracy of sound (detail stored about amplitude of sound)
- memory usage of file as bits used to store data
8
Q
what is sample rate
A
number of bits per sample
9
Q
what is image resolution
A
number of pixels in image
9
Q
effect of image resolution
A
- more detail
- use more memory
9
Q
effects of sample rate
A
- more accurate sound (fewer estimations between samples)
- increase file size
10
Q
how computer represents image
A
- series of pixels
- converted to binary
- processed by computer
11
Q
what is image resolution
A
number of pixels that make up an image
12
Q
what is colour depth
A
number of bits representing each colour
12
Q
effect of colour depth
A
- higher quality (more colours)
- increase file size
