Provides a function to reduce the number of colours in an image.

func doQuantising(in image.Image) image.Image {
  return quantise.Quantise(in, quantise.OctreeQuantiser{
    Depth: 6,
    Size: 50,
    Strategy: quantise.LEAST,
  })
}

• Depth gives the maximum depth the tree can reach, the deeper the tree the greater the detail can be captured, kinda anyway.

• Size is the number of colours to use in the final image.

• Strategy is either LEAST in which case the colours representing the fewest pixels are merged, or MOST which merges the colours representing the most.

The results aren't very accurate.

There is a simple command line wrapper available:

$ go get hawx.me/code/quantise/cmd/quantise
$ quantise --depth 6 --size 128 < input.png > output.png