View Single Post
Old 13th March 2018, 16:52   #2
Major Dude
Join Date: Mar 2008
Location: Erlangen
Posts: 926
Virtually all presets react to changes of bass, mid and treb signal. These signals are what their name implies, and sum over left and right channel. A number of different schemes have been devised, using different weighting, time constants and other mysterious factors but basically they all react to changes in these signals. Some try to create a trigger signal (a "beat") on which they react, others change zoom or other movement or distortion parameters by volume (or by any mixture of bass,mid,treb; by a weighted mixture; by a nonlinearly weighted mixture, using sqare or square root or whatever else).

A qualitatively different scheme is my own harmonic beat detection. It is still based on bass,mid,treb, but rather than reacting instantaneously it tries to fall into pace with the music and find the rhythm, like a pendulum. It can be quite impressive but only works well with rhythmic music, may take a few seconds to find the rhythm, and it may appear off-beat, therefore I used it sparingly.

AFAIK there are no presets that react to pitch or notes (other than showing a waveform or harmonic spectrum). Left and right channel have neither been used either, and none of this would have been possible anyway with milkdrop before Benski introduced the ns-eel language extension in 2009.

You may of course study the code in the per frame section but trust me that will hardly give you any insight. The appearance of presets depends on much more than the beat detection, and some of the schemes devised are so convoluted that you have no chance to understand them anyway.
Give me a few examples of what presets suits you, maybe I can tell you more.
Nitorami is offline   Reply With Quote