Anya scans an image into her computer for a school project.
The scanned image is a bitmapped image.
(a)(i) Complete the following table to describe the two terms about graphics.
| Term | Description |
|---|---|
| Pixel | |
| File header |
(a)(ii) The image is scanned with an image resolution of 1024 × 512 pixels, and a colour depth of 8 bits per pixel.
Calculate an estimate for the file size, giving your answer in mebibytes. Show your working.
(b) The image is compressed using lossless compression.
Identify one method of lossless compression that can be used to compress the image and describe how the method will reduce the file size.
(c)(i) One of the colours used in the image has the hexadecimal colour code: #FC238A
FC is the amount of red, 23 is the amount of green and 8A is the amount of blue in the colour.
Convert the hexadecimal code FC into denary.
(c)(ii) The amount of green in binary is 00100011. This has the denary number 15 added to it to create a second colour.
Add the denary number 15 to the binary number 00100011 and give your answer in binary. Show your working.
(c)(iii) Hexadecimal 23 in two's complement representation is 00100011. The denary number 10 needs to be subtracted from this value.
Subtract the denary number 10 from the two's complement representation 00100011. Give your answer in binary. Show your working.