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Pink noise image masks

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

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.