Add some lua scripts

scripts/voice_activate.lua

@@ -0,0 +1,49 @@
+ardour {
+	["type"]    = "dsp",
+	name        = "Voice/Level Activate",
+	license     = "MIT",
+	author      = "Robin Gareus",
+	authoremail = "robin@gareus.org",
+	site        = "http://gareus.org",
+	description = [[
+	An Example Audio Plugin that rolls the transport
+	when the signal level on the plugin's input a given threshold.]]
+}
+
+function dsp_ioconfig ()
+	return
+	{
+		{ audio_in = -1, audio_out = -1},
+	}
+end
+
+function dsp_params ()
+	return
+	{
+		{ ["type"] = "input", name = "Threshold", min = -20, max = 0, default = -6, doc = "Threshold in dBFS for all channels" },
+		{ ["type"] = "output", name = "Level", min = -120, max = 0 },
+	}
+end
+
+function dsp_configure (ins, outs)
+	n_channels = ins:n_audio();
+end
+
+-- use ardour's vectorized functions
+function dsp_runmap (bufs, in_map, out_map, n_samples, offset)
+	local ctrl = CtrlPorts:array() -- get control port array (read/write)
+	if Session:transport_rolling() then ctrl[2] = -math.huge return end
+	local threshold = 10 ^ (.05 * ctrl[1]) -- dBFS to coefficient
+	local level = -math.huge
+	for c = 1,n_channels do
+		local b = in_map:get(ARDOUR.DataType("audio"), c - 1); -- get id of buffer for given cannel
+		if b ~= ARDOUR.ChanMapping.Invalid then
+			local a = ARDOUR.DSP.compute_peak(bufs:get_audio(b):data(offset), n_samples, 0)
+			if a > threshold then
+					Session:request_transport_speed(1.0, true)
+			end
+			if a > level then level = a end
+		end
+	end
+	ctrl[2] = ARDOUR.DSP.accurate_coefficient_to_dB (level)
+end