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Compressing a picture by counting repeats

A black-and-white icon often contains long rows of identical white pixels followed by a few black ones. Instead of listing every single pixel one by one, run-length encoding stores the color once and counts how long the streak lasts, shrinking simple graphics dramatically, though a noisy photograph can actually grow larger.

3–5 min

Questions you could explore

  • What rules allow the original picture to be reconstructed?
  • When could counting runs take more space than storing pixels directly?

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Compressing a picture by counting repeats | Speech Topic | speaking.app