Selecting the Effects Levels 1.1 2006/12/20 15:26:24.055 US/Central 2006/12/20 16:26:02.788 US/Central Rob Smith rob@rice.edu Rob Smith rob@rice.edu distortion Effects Electric Guitar flange Guitar Guitar Effects reverb This module talks about how the proper effects levels are selected from the provided data. Once the song has been processed by findChords and beatDetect, the proper effects levels need to selected. The levels are calculated 6 times a second throughout the song using the values returned by the findChords and beatDetect methods.

Beats and Chords Over Song This graph holds the beat and chord information for the length of Mixed Phantom and Riff.wav This data is used to calculate the proper effects levels.

This beat and chord data is compared with presets in the program to determine the proper effects levels for each 1/6th of a second chunk of the song. These presets are designed for heavy metal music, but they could be easily adapted for any other music styleEffects Presets Fast Playing Slow Playing Single Notes 100% Distortion, No Reverb 75% Distortion, 40% Reverb Chords 75% Distortion, No Reverb 60% Distortion, 100% Reverb Flange is handled differently than the other two effects. Flange is proportionally added whenever the beat count drops below two. If the beat count is zero, the piece will have 100% flange applied.The effects quantity calculations produce a vector for each effect with values ranging for 0 to 1. A value of 0 means do not apply any effect at all, while 1 means apply the maximum quantity of that effect.

Effect Levels Over Song The quantity of each effect to apply during each section of the song.

These vectors are low pass filtered before the effects are applied to the song. This guarantees a smooth and musical transition between different effects styles, and also prevents any momentary deviations in our detection algorithms from changing the output. In practice, you don't want the effect style changing for every different note you hit, so our low pass filter does an excellent job of melding segments together to create a consistant level of effects for your current overall style of play.

This is the sample file used for the graphs in this article without any effects applied.

This is the sample file used for the graphs in this article with the effets applied by our program.