TMA 3

Q1. Describe how bit-mapped graphics are stored.

Q2. Describe how vector graphics are stored.

Q3. A company logo shown below has been created using a bitmapped graphics package. The image measures 300 * 200 pixels and the palette used consists of 256 greyscale. How many bytes will be needed to store the logo?

Q4. A scanner is used to scan a 4 inch * 6 inch photograph into a computer. The scanner resolution is set at 600 dpi with 256 colours.

How much memory would be required to store the scanned image?

Q5. A black and white photograph measures 2 inches * 2 inches. It is scanned at 600 dpi.

Calculate the size of file when this image is saved to the hard disk?

Q6. Describe the term “24 bit colour”.

Q7. Describe the term “floating point representation”?

Q8. A floating-point format uses four bytes for the mantissa and one byte for the exponent. If this is changed to three and two bytes respectively, what effect will this have on:

a) the accuracy and

b) range of the numbers stored?

Q9. Give one reason why a computer is often described as a “two-state machine”.

Extension Question.

All modern computers are stored program machines made from two-state devices.

a) Explain what is meant by the stored program concept.

b) Digital computers use binary codes to represent data. Give two reasons why computers are based on the binary number system.