ardour { ["type"] = "dsp", name = "NoiseGen", category = "Instrument", license = "MIT", author = "Ardour Team", description = [[Noise Generator (v-1.02)]] } function dsp_params () return { { ["type"] = "input", name = "White/Pink", min = 0, max = 1, default = 0, toggled = true }, { ["type"] = "input", name = "Gain", min = -60, max = 0, default = -18, unit="dB" }, } end function dsp_ioconfig () return { [1] = { audio_in = -1, audio_out = -1}, } end local ao = 0 function dsp_run (ins, outs, n_samples) local a = {} -- init array local ctrl = CtrlPorts:array () local noise = ctrl[1] or 0 local amplitude = ARDOUR.DSP.dB_to_coefficient (ctrl[2]) or ARDOUR.DSP.dB_to_coefficient (-18) local b0 = 0.0 local b1 = 0.0 local b2 = 0.0 local b3 = 0.0 local b4 = 0.0 local b5 = 0.0 local b6 = 0.0 --Pink noise generation courtesy of Paul Kellet's refined method --http://www.musicdsp.org/files/pink.txt --If 'white' consists of uniform random numbers, --the pink noise will have an almost gaussian distribution. for s = 1, n_samples do if noise == 0 then a[s] = amplitude * 2 * (math.random() - 0.5) end if noise == 1 then white = (amplitude * 0.25) * 2 * (math.random() - 0.5) b0 = 0.99886 * b0 + white * 0.0555179; b1 = 0.99332 * b1 + white * 0.0750759; b2 = 0.96900 * b2 + white * 0.1538520; b3 = 0.86650 * b3 + white * 0.3104856; b4 = 0.55000 * b4 + white * 0.5329522; b5 = -0.7616 * b5 - white * 0.0168980; b6 = white * 0.115926; a[s] = b0 + b1 + b2 + b3 + b4 + b5 + b6 + white * 0.5362; end end -- passes array a {} into buffer for c = 1,#outs do outs[c]:set_table(a, n_samples) end if (a ~= ao) then self:queue_draw() end ao = amplitude end function render_inline (ctx, w, max_h) --inline display local ctrl = CtrlPorts:array() h = 30 p = 0 inc = 0 ycy = 0.5 pink = false local amplitude = ARDOUR.DSP.dB_to_coefficient(ctrl[2]) if ctrl[1] == 1 then pink = true end if pink then inc = 0.7/w end --draw rectangle ctx:rectangle(0, 0, w, h) ctx:set_source_rgba(0, 0, 0, 1.0) ctx:fill() ctx:set_line_width(1.5) ctx:set_source_rgba(0.8, 0.8, 0.8, 1.0) l_x = 0 l_y = 0 for x = 0,w do if pink then ycy = 0.3 else ycy = 0.5 end --slant slightly like an actual pink noise spectrum y = math.log(20^amplitude) * (math.random() - 0.5) - p yc = ycy * h + ((-0.5 * h) * y) ctx:move_to (x, yc + 3) ctx:line_to (l_x, l_y + 3) l_x = x l_y = yc ctx:stroke() p = p + inc end return {w, h + 6} end