3 name = "Voice/Level Activate",
5 author = "Ardour Lua Task Force",
7 description = [[Roll the transport when the signal level on the plugin's input exceeds a given threshold.]]
10 function dsp_ioconfig ()
13 -- support all in/out as long as input port count equals output port count
14 { audio_in = -1, audio_out = -1},
18 function dsp_params ()
21 { ["type"] = "input", name = "Threshold", min = -20, max = 0, default = -6, doc = "Threshold in dBFS for all channels" },
22 { ["type"] = "output", name = "Level", min = -120, max = 0 },
26 function dsp_configure (ins, outs)
27 n_channels = ins:n_audio()
30 function dsp_runmap (bufs, in_map, out_map, n_samples, offset)
31 local ctrl = CtrlPorts:array() -- get control port array (read/write)
33 if Session:transport_rolling() then
34 -- don't do anything if the transport is already rolling
35 ctrl[2] = -math.huge -- set control output port value
39 local threshold = 10 ^ (.05 * ctrl[1]) -- dBFS to coefficient
40 local level = -math.huge
42 for c = 1,n_channels do
43 local b = in_map:get(ARDOUR.DataType("audio"), c - 1) -- get id of audio-buffer for the given channel
44 if b ~= ARDOUR.ChanMapping.Invalid then -- check if channel is mapped
45 local a = ARDOUR.DSP.compute_peak(bufs:get_audio(b):data(offset), n_samples, 0) -- compute digital peak
47 Session:request_transport_speed(1.0, true)
49 if a > level then level = a end -- max level of all channels
52 ctrl[2] = ARDOUR.DSP.accurate_coefficient_to_dB (level) -- set control output port value