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Pink noise image masks

#1

Hi guys,

I was wondering if anyome has created a pink noise mask from the images used in their experiments. I had a look at the NoiseStim component and it says that noiseFractalPower is controlling the frequency bias, with -1 being brownian noise. If that is the case would a value of, say -0.7, be closer to the pink noise distribution?

Best,
Miguel

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#2

Setting the noiseFractalPower sets the amplitude of each component in the noise spectrum to its spatial frequency raised to the indicated power. Pink noise is defined as a power spectral denisity this relates to the amplitude spectrum differently for 1D and 2D signals. So you need to work though the maths to find the most appropriate setting.

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