4 ms·
The DFF-Mono pattern is interesting because of how if you reduce the high-cut you can see the bands disappearing step-wise in decreasing density... I assume thi
by phab 6y ago
The DFF-Mono pattern is interesting because of how if you reduce the high-cut you can see the bands disappearing step-wise in decreasing density... I assume this occurs as the Nyquist frequency is passed for those pixels?
- klodolph 6y ago> I assume this occurs as the Nyquist frequency is passed for those pixels? No, the Nyquist frequency isn’t the relevant parameter here. What is happening here is that you have a low-pass filter with a very steep cutoff (or high-pass, depending on what you are sweeping). As you sweep the cutoff, because the filter is so steep, the band suddenly disappears when the content moves from one side of the cutoff to the other.
- DougBTX 6y agoThe "grid" example shows a similar effect, but the difference is even more stark. With Low Cut Frequency at 0%, slowly move the High Cut Frequency between 7% and 9%, on the "Modulus view" you should see the white dots which represent vertical bands in the "Inverse transform" get cut out, so the "Inverse transform" switches from a fuzzy grid to just horizontal bands.