Computer Science 9618/12 — May/June 2022
Cambridge AS Level · Theory Fundamentals · worked solutions for every part, with the mark scheme
Topics Information Representation · Hardware · Processor Fundamentals · Security, Privacy and Data Integrity · Databases · System Software · +2 more
Draw one line from each image representation term to its correct definition.
| Term | Definition |
|---|---|
| Pixel | The number of pixels wide by the number of pixels high |
| Bit depth | The smallest identifiable component of an image |
| Image resolution | Stores data about the image file, e.g. file format, number of bits per pixel, file size |
| File header | The number of bits used to represent each colour |
The following section of a bitmap image is 10 pixels wide and 5 pixels high. In this example, each colour is represented by a letter, e.g. B is blue.
| B | B | B | B | B | B | B | B | B | B |
| Y | Y | P | Y | Y | Y | P | Y | Y | Y |
| R | R | M | R | P | K | T | T | R | R |
| B | O | P | Y | Y | Y | P | G | P | P |
| R | O | R | P | P | P | R | R | R | R |
The complete image can have up to 256 colours.
Identify the smallest number of bits that can be used to represent each colour in the complete bitmap image.
Calculate an estimate for the file size of the section of the bitmap image shown, giving your answer in bytes. Use your answer from part (b)(i).
Show your working.
Working .............................................................................................................................
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Answer ................................... bytes
Describe how changing the colour depth of an image affects its file size.
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The first row of pixels in the image from part (b) is shown:
| B | B | B | B | B | B | B | B | B | B |
|---|
Explain how this row of pixels can be compressed using lossless compression.
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The rest of this paper
8 more questions- Q2Hardware5M
- Q3Processor Fundamentals · Information Representation9M
- Q4Security, Privacy and Data Integrity10M
- Q5Databases17M
- Q6System Software8M
- Q7Hardware2M
- Q8Ethics and Ownership3M
- Q9Communication11M