Information rep

Question 1

Bit depth

Answer 1

The number of bits used to represent a single pixel

Question 2

Color depth

Answer 2

Maximum number of color that an image can contain also depends on the bit depth

Question 3

Image resolution

Answer 3

refers to the number of pixels that make up an image

Question 4

Screen resolution

Answer 4

Refers to the number of horizontal pixels and vertical pixels that make up the screen display

Question 5

Advantages of vector graphics

Answer 5

No pixelation when it is zoomed in
It is easier to edit
Vector graphics are stored as instructions

Question 6

Lossless and lossy compression

Answer 6

lossless - Doesn’t lose data, no corruption of data
Uses RLE
lossy - loses data, data file is corrupted, cannot be restored back to its original form.

Question 7

Why does sound need to be digitized
What coverts it from analogue to digital

Answer 7

Sound in an analogue form so it needs to be digitized to store it in a computer
ADC - analogue to digital convertor

Question 8

Sampling resolution

Answer 8

resolution is the number of distinct values available to encode/represent each
sample
• specified by the number of bits used to store/record each sample
• sometimes referred to as bit depth
• the higher the sampling resolution, the smaller the quantization error
• a higher sampling resolution results in less distortion of the sound
• usually 8 bit, 16 bit, 24 bit or 32 bit

Question 9

What affects the size of a bit map image

Answer 9

Color depth- when decreased file size decreases

Question 10

What affects the accuracy of a sound file

Answer 10

Sampling rate and sampling resolution

Question 11

Calculations
File size
Image size

Answer 11

File size - sampling frequency(rate) x sampling size( resolution) x time
Image size -( width x height x color depth(in bits))/8 (which converts it to bytes)