Understanding Colour Depth in Images

What is colour depth?

• The number of pixels in an image

• The number of bits used to represent the colour of a single pixel

• The width of an image in pixels

• The brightness of an image

How many colours can be represented in an image with a colour depth of 8 bits?

• 16

• 64

• 256

• 1024

How many different colours can be represented with a colour depth of 4 bits?

• 4

• 8

• 16

• 32

What is the formula used to calculate the number of colours available given the colour depth?

• <katex latex="2^{\text{number of pixels}}"></katex>

• <katex latex="2^{\text{colour depth}}"></katex>

• <katex latex="\text{colour depth} \times 2"></katex>

• <katex latex="\text{colour depth}^2"></katex>

An image has a colour depth of 2 bits. How many different colours can be represented?

• 2

• 4

• 8

• 16

A bitmap image is 800 pixels wide and 600 pixels tall, with a colour depth of 24 bits. What is the size of the image in bytes?

• 1,440,000 bytes

• 480,000 bytes

• 14,400 bytes

• 2,400 bytes

An image is stored using 256 different colours. What is the colour depth of the image in bits?

• 4 bits

• 6 bits

• 8 bits

• 16 bits

Which of the following best explains the effect of increasing colour depth on file size?

• File size decreases

• File size stays the same

• File size increases

• File size is not affected

Which of the following best explains the effect of increasing colour depth on image quality?

• Image quality decreases

• Image quality stays the same

• Image quality increases

• Image quality is not affected

If you are designing a game for mobile devices, what is a likely trade-off between using a 16-bit colour depth versus a 24-bit colour depth?

• 16-bit uses more storage but has better quality

• 24-bit uses less storage but has worse quality

• 16-bit uses less storage but has slightly lower quality

• 24-bit uses less storage and has better quality