Storing Images

Question 1

Bitmap Images

Answer 1

Made up of pixels
most images e.g. photos are stored in bitmap

Question 2

How is the colour of each pixel represented?

Answer 2

Binary
Number of colours available -> number of bits the code has

Question 3

How many bits do black and white images have

Answer 3

2 bits
0 = white
1 = black

Question 4

Colour Depth

Answer 4

number of bits for each pixel
Total number of pixels = 2’n

Question 5

Image Resolution

Answer 5

Number of pixels in the image

Width x Height

Higher resolution = higher quality image

Question 6

File Size

Answer 6

How many bits an image will take up

File size (in bits) = image resolution x colour depth

OR
File size (in bits) = width x height x colour depth

Question 7

Metadata

Answer 7

information stored in an image file which helps the computer recreate the image on screen from binary data each pixel

Question 8

Metadata includes:

Answer 8

File format
Height
Width
Colour depth
Resolution

-> without metadata devices wouldn’t be able to display the image on screen as intended

Question 9

Vector images

Answer 9

Made up of simple shapes that are different blocks of colour

e.g. computer made graphics