@hackage hdf0.15

hdf - haskell data flow

Haskell library for uniform rate audio signal processing.

It generates C code that requires either RDL (from sc3-rdu) or jack-dl (from rju).

The SC2 analog bubbles graph can be written:

  let o = lf_saw (mce2 8.0 7.23) 0.0 * 3.0 + 80.0
      m = lf_saw 0.4 0.0 * 24.0 + o
      s = sin_osc (midi_cps m) 0.0 * 0.04
      c = comb_n [0,1] 0.4 s 0.2 4.0
  in out c

The data flow graph this generates is:

The generated C-code (for jack-dl) is c/gen/analog-bubbles.c.

Slightly more elaborate, the berlin 1977 graph can be written:

    let clock_rate = 9
        clock_time = 1 / clock_rate
        clock = impulse clock_rate 0 -- sequencer trigger
        tr = trigger clock
        note = sequ 0 [55,60,63,62,60,67,63,58] tr -- midi note pattern sequencer
        tr_16 = pulse_divider tr 16 0 -- divide tr by 16
        note' = sequ 1 [-12,-7,-5,0,2,5] tr_16 + note -- transpose
        freq = midi_cps note' -- convert midi note to cycles per second
        env = decay2 clock (0.05 * clock_time) (2 * clock_time)
        amp = env * 0.1 + 0.02 -- amplitude envelope
        filt = env * (sin_osc 0.17 0 * 800) + 1400 -- filter frequency
        pw = sin_osc (mce2 0.08 0.09) 0 * 0.45 + 0.5 -- pulse width LFO(s)
        s = lf_pulse freq 0 pw * amp -- not bandlimited
    in out (comb_n [0,1] 0.2 (rlpf s filt 0.15) (mce2 0.2 0.17) 1.5)

The data flow graph this generates is:

The generated C-code (for jack-dl) is c/gen/berlin-1977.c.

hdf implements text-dl for testing.

© rohan drape, 2006-2014, gpl