Compression

Lesson Instructions

Watch and follow the YouTube video, the lesson contains three parts:

  1. Key Information and content - all you need to do here is watch and listen

  2. Learning activity - this activity involves answering different questions about Compression

  3. Consolidation - these are past exam question and are for deliberate practice to check your understanding.

Task - Lossy Vs Lossless

Task - Exam Questions - Deliberate Practice

Exam Questions - Web

Mark Scheme

Question 8 (a)

  • Reduce the size of the file

  • Transmits more quickly / uses less bandwidth - Accept other advantages to do with sending files.

Question 8 (b) (i)

  • Lossless compression

  • The code has to be exactly as it was originally written...

  • ...Or else it will not work

Question 8 (b) (ii)

  • Lossy compression

  • Achieves higher compression / smaller file size / faster streaming than lossless

  • Video can still be viewed at a lower quality (from the data compressed)