Symmetrical Pixel Puzzles: Easter

In symmetrical colour by number pictures you are only given the numbers for half the pictures. Use symmetry to work out the rest of the numbers and so the rest of the picture.

If you know something about the properties of a picture you can reconstruct the image despite storing fewer numbers! That is called image compression.


EasterChickSymmetry16x16Some squares have a number that tells you the colour to colour in that square. Look up the colours in the key. Other squares have no number. Work out what colour they are by symmetry.

So, for example with a colour lookup table  1 Blue, 2 Red  a row with numbers (where _ means blank)  1 1 1 1 1 2 2 2 _ _ _ _ _ _ _ _  would mean colour five pixels blue and then by symmetry three pixels red,  then three pixels red and five pixels blue.

Complete them in either of two ways (two algorithms). Either:

  1.  Use symmetry to first fill out the rest of the grid of numbers to create a normal colour by number pixel, OR
  2. Colour in the numbers given, then copy the colours on to the other side.

Easter Picture

by Elisa Huen

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