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Why is this on Hacker News?

• jonmrodriguez 13y ago
  It's great content, relevant to our readership, and it's new (dated July 27, 2013). It's a cool "aha! moment" when you realize that using Look-Up Tables you can implement any Single-Point image transformation entirely using array lookup operations (no if statements or nonlinear math).
  • DougWebb 13y ago
    You need the if statements and nonlinear math to create the look-up tables.
    • enigmoid 13y ago
      Not to create the lookup table in the example. And I love reading about applications of linear algebra like this. Makes me want to write my own image processing algorithms as practice.
  • OMBUG 13y ago
    To be fair you can implement any function over a finite domain using a sufficiently large lookup table. The OP seems weird - it's clearly a beginner asking, but the answers assume an understanding of spatial frequency and Fourier transforms. I think it would be more intuitive to explain in terms of convolutions with small kernels.
  • theoh 13y ago
    Really? For my money cool would be something like http://www.graficaobscura.com/interp/ http://www.graficaobscura.com/interp/
    • GrantS 13y ago
      That's great, both conceptually and from an ease-of-implementation perspective. Somehow I've never encountered that work, thanks for pointing it out!