ardour { ["type"] = "dsp", name = "Simple Amp", category = "Example", license = "MIT", author = "Ardour Lua Task Force", description = [[ An Example DSP Plugin for processing audio, to be used with Ardour's Lua scripting facility.]] } -- return possible i/o configurations function dsp_ioconfig () -- -1, -1 = any number of channels as long as input and output count matches return { [1] = { audio_in = -1, audio_out = -1}, } end -- optional function, called when configuring the plugin function dsp_configure (ins, outs) -- store configuration in global variable audio_ins = ins:n_audio(); local audio_outs = outs:n_audio() assert (audio_ins == audio_outs) end -- this variant asks for a complete *copy* of the -- audio data in a lua-table. -- after processing the data is copied back. -- -- this also exemplifies the direct "connect and run" process function, -- where the channel-mapping needs to be done in lua. function dsp_runmap (bufs, in_map, out_map, n_samples, offset) for c = 1,audio_ins do -- Note: lua starts counting at 1, ardour's ChanMapping::get() at 0 local ib = in_map:get(ARDOUR.DataType("audio"), c - 1); -- get id of mapped input buffer for given channel local ob = out_map:get(ARDOUR.DataType("audio"), c - 1); -- get id of mapped output buffer for given channel assert (ib ~= ARDOUR.ChanMapping.Invalid); assert (ob ~= ARDOUR.ChanMapping.Invalid); local a = bufs:get_audio (ib):data (offset):get_table(n_samples) -- copy audio-data from input buffer for s = 1,n_samples do a[s] = a[s] * 2; -- amplify data in lua table end bufs:get_audio(ob):data(offset):set_table(a, n_samples) -- copy back end end