Harmonizing with the Background
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3. Create a never-ending tune from based upon the base frequency.
Via OSC I can send the FFT-derived base-frequency to a Raspberry Pi running Pd-extended. With PD, tone generation is as simple as connecting a few nodes, and song generation is just a little bit more complicated than that.
A series of specific whole-number ratios multiplied by a frequency result in natural harmonies: for example, the base-frequency times five-fourths results in a Major Third above the base; fifteen-eights is a Major Seventh.
Using this knowledge in combination with a basic chord progression and a little randomness, I can create a never-ending song that perpetually realigns itself to the incoming frequency.