ardour { ["type"] = "dsp", name = "Spike Synth", category = "Instrument", license = "MIT", author = "Ardour Lua Task Force", description = [[A debug and test-instrumentation synth. This plugin is useful with Ardour's "Dummy" backend "Engine-Pulse" mode to verify capture alignment. This plugin generate the exact same audio-signal from MIDI data that the backend also generates: Note-on: +1, Note-off: -1.]] } function dsp_ioconfig () return { { midi_in = 1, audio_in = 0, audio_out = 1} } end function dsp_run (ins, outs, n_samples) local a = {} for s = 1, n_samples do a[s] = 0 end for c = 1,#outs do ARDOUR.DSP.memset (outs[c], 0, n_samples) end assert (type(midiin) == "table") for _,b in pairs (midiin) do local t = b["time"] -- t = [ 1 .. n_samples ] local d = b["data"] -- get midi-event if (#d == 3 and (d[1] & 240) == 144) then -- note on for c = 1,#outs do outs[c]:array()[t] = 1.0 end end if (#d == 3 and (d[1] & 240) == 128) then -- note off for c = 1,#outs do outs[c]:array()[t] = -1.0 end end end end