Tech WondersPlay

Images, Screens & GamesImage Compression

How JPEG Shrinks Photos

Photos shrink by throwing away detail your eyes barely notice

Most photos online are shrunk to a fraction of their full size. So what gets thrown away, and why does it still look fine?

You'll find out

  • How a photo becomes 8-by-8 tiles
  • Which details vanish first
  • Where the blocks come from

Why it matters

It shows how files get small by spending detail where your eyes notice it least, a trick sound and video use too.

About 4 min7 interactive slides · 5 questionsLesson 213 · Zone 24

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