Multimedia - Graphics — practice questions

1. Calculate total pixels: $1024 \times 768 = 786,432$ pixels
2. Calculate total bits: Total pixels $\times$ Colour Depth $786,432 \times 16 = 12,582,912$ bits
3. Convert bits to bytes: Divide by 8 $12,582,912 \div 8 = 1,572,864$ bytes
4. Convert bytes to kilobytes (KB): Divide by 1024 $1,572,864 \div 1024 = 1,536$ KB
5. Convert kilobytes to megabytes (MB): Divide by 1024 $1,536 \div 1024 = 1.5$ MB

Answer: 1.5 MB

1. Understand the relationship: The number of colours is determined by $2^{\text{colour depth}}$. We need to find the colour depth (let's call it $d$).
2. Set up the equation: $2^d = 4096$
3. Solve for d: We need to find the power to which 2 must be raised to get 4096. This is the logarithm base 2. $d = \log_2(4096)$
4. Calculation: You can solve this by recognising powers of 2: $2^{10} = 1024$ $2^{11} = 2048$ $2^{12} = 4096$

Answer: The colour depth is 12 bits.