Measure PWM using Free Software and a 192KHz Sound Card

[ToyKeeper]

@jeff51

Taking a look at these lights, especially the ones with a crappy PWM, perhaps some minimum standards could be established …

There’s already something we call the “snob index”:

Approximating flicker visibility

Just wanted to share a little thing I and mostly parametrek have been doing to assess the visibility of flickering/pwm on lights. The basic idea came from derlichtpeter.de whose CFD index tries to convey in a single value how visible flickering is. We just call it the snob index, but the technique is similar. This is still very much work in progress and uses a modified curve from the CFD. It takes into account the modulation/flicker frequency and its other fft harmonics, percent modulation and …

Basically, for a standard, we could say that lights must have a snob index of less than 5%, or something like that?