This function uses brownian noise to determine the degree to which random fluctuations will occur in the pattern. This is a kind of melodic and harmonic humanizer that generates natural fluctuations breaking the rigid fractal structure (of gen-trans, for example) and yet still preserving the characteristics of the original.
Seed and smooth-value initializes the brownian generator. Lower and upper control the lower and upper limits of the modifications. Note that rest symbol = is preserved as it is. The transpose values are not touched but the symbol values can be variated.