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Representing Images — Pixels & Colour Depth

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  • 8 questions
  • 25 marks
  • about 30 minutes
  • marked instantly

Question types: multi-part, short answer, multiple choice, true or false, matching.

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A photo is zoomed in so far that you can see individual solid-colour squares making up the image. What is each of these squares called?

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About this resource

Computing — Binary & the Language of Computers, Lesson 5. How a bitmap image is a grid of pixels, each pixel's colour stored as a binary number, and how resolution and colour depth affect quality and file size.

11 slides.

Lesson outline

  1. Do Now — Retrieval
  2. Every Picture is a Grid
  3. Quick Check — What is a Pixel?
  4. Pixel Grid Explorer
  5. How Many Colours? Colour Depth
  6. Hinge Check — Blocky or Dull?
  7. Resolution, File Size, and the Trade-off
  8. Main Activity — Calculate Image File Size
  9. Plenary — Back to Our Objectives
Unit bundleBinary
Part of: Binary: the whole unitEvery resource in the unit in one zip.

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