Work through the list without notes. If you cannot do a statement, follow its link, then come back. Guide = study guide; Practice = practice questions.
Understanding
- I can explain what data compression is and why fewer bits does not necessarily mean less information. (Guide: “Why compress data?”; Practice Q2)
- I can explain what lossless compression guarantees. (Guide: “Lossless compression”; Practice Q1)
- I can explain what lossy compression allows and why it can usually reduce size more. (Guide: “Lossy compression”; Practice Q5)
- I can say what the saving depends on (redundancy and algorithm). (Guide: “Why compress data?”; Practice Q7)
Skills
- I can run-length encode a string and decode a run-length code. (Guide: Worked example 1; Practice Q3, Q4)
- I can calculate the percentage saved from the original and compressed sizes. (Guide: Worked examples 1 and 2; Practice Q8)
- I can show that a scheme is lossless by decoding it. (Guide: Worked example 1 part (c); Practice question 10)
Reasoning
- I can choose lossless or lossy for a situation and justify it with the priority. (Guide: “Choosing between them”; Practice Q6, Q9)
- I can name the trade-off of a compression choice. (Guide: Worked example 2; Practice Q9)
- I can give an example where a compression method fails to save space and explain why. (Guide: “Lossless compression”; Practice question 10)
All ticked? Move on to the Topic 2.3 study guide, Extracting Information from Data.