Add Lua script to send 12TET tuning as MTS messages
This commit is contained in:
parent
89f91324d4
commit
c5cca7680e
GPG Key ID:
A090BCE02CF57F04
|
|
@ -0,0 +1,198 @@
|
|||
ardour {
|
||||
["type"] = "EditorAction",
|
||||
name = "MIDI Tuning",
|
||||
license = "MIT",
|
||||
author = "Ardour Team",
|
||||
description = [[generate MIDI tuning standard (MTS) messages for 12TET pitch changes]]
|
||||
}
|
||||
|
||||
function factory () return function ()
|
||||
|
||||
-- return table of all MIDI tracks, and all instrument plugins.
|
||||
--
|
||||
-- MidiTrack::write_immediate_event() injects MIDI events to the track's input
|
||||
-- PluginInsert::write_immediate_event() sends events directly to a plugin
|
||||
function midi_targets ()
|
||||
local rv = {}
|
||||
for r in Session:get_tracks():iter() do
|
||||
|
||||
if not r:to_track():isnil() then
|
||||
local mtr = r:to_track():to_midi_track()
|
||||
if not mtr:isnil() then
|
||||
rv["Track: '" .. r:name() .. "'"] = mtr
|
||||
end
|
||||
end
|
||||
|
||||
local i = 0;
|
||||
while true do
|
||||
local proc = r:nth_plugin (i)
|
||||
if proc:isnil () then break end
|
||||
local pi = proc:to_plugininsert ()
|
||||
if pi:is_instrument () then
|
||||
rv["Track: '" .. r:name() .. "' | Plugin: '" .. pi:name() .. "'"] = pi
|
||||
end
|
||||
i = i + 1
|
||||
end
|
||||
end
|
||||
return rv
|
||||
end
|
||||
|
||||
function log2 (v)
|
||||
return math.log (v) / math.log (2)
|
||||
end
|
||||
|
||||
-- calculate MIDI note-number and cent-offset for a given frequency
|
||||
--
|
||||
-- "The first byte of the frequency data word specifies the nearest equal-tempered
|
||||
-- semitone below the frequency. The next two bytes (14 bits) specify the fraction
|
||||
-- of 100 cents above the semitone at which the frequency lies."
|
||||
--
|
||||
-- 68 7F 7F = 439.9984 Hz
|
||||
-- 69 00 00 = 440.0000 Hz
|
||||
-- 69 00 01 = 440.0016 Hz
|
||||
--
|
||||
-- NB. 7F 7F 7F = no change (reserved)
|
||||
--
|
||||
function freq_to_mts (hz)
|
||||
local note = math.floor (12. * log2 (hz / 440) + 69.0)
|
||||
local freq = 440.0 * 2.0 ^ ((note - 69) / 12);
|
||||
local cent = 1200.0 * log2 (hz / freq)
|
||||
-- fixup rounding errors
|
||||
if cent >= 99.99 then
|
||||
note = note + 1
|
||||
cent = 0
|
||||
end
|
||||
if cent < 0 then
|
||||
cent = 0
|
||||
end
|
||||
return note, cent
|
||||
end
|
||||
|
||||
local dialog_options = {
|
||||
{ type = "number", key = "tuning", title = "Tuning A4 (Hz)", min= 220.0, max = 880.0, default = 440.0, digits = 1, step = 0.1 },
|
||||
{ type = "dropdown", key = "tx", title = "MIDI SysEx Target", values = midi_targets () }
|
||||
}
|
||||
|
||||
local rv = LuaDialog.Dialog ("MIDI Tuning", dialog_options):run ()
|
||||
dialog_options = nil -- drop references (track, plugins, shared ptr)
|
||||
collectgarbage () -- and release the references immediately
|
||||
|
||||
if not rv then return end -- user cancelled
|
||||
|
||||
-- prepare sending data
|
||||
local tx = rv["tx"] -- output port
|
||||
local ref_freq = rv["tuning"] -- ref freq (440.0)
|
||||
local parser = ARDOUR.RawMidiParser () -- construct a MIDI parser
|
||||
local checksum = 0
|
||||
|
||||
-- helper function to send MIDI
|
||||
function tx_midi (syx, len, hdr)
|
||||
for b = 1, len do
|
||||
--dump:write (string.char(syx:byte (b)))
|
||||
|
||||
-- calculate checksum, xor of all payload data
|
||||
-- (excluding the 0xf0, 0xf7, and the checksum field)
|
||||
if b >= hdr then
|
||||
checksum = checksum ~ syx:byte (b)
|
||||
end
|
||||
|
||||
-- parse message to C/C++ uint8_t* array (Validate message correctness. This
|
||||
-- also returns C/C++ uint8_t* array for direct use with write_immediate_event.)
|
||||
if parser:process_byte (syx:byte (b)) then
|
||||
tx:write_immediate_event (Evoral.EventType.MIDI_EVENT, parser:buffer_size (), parser:midi_buffer ())
|
||||
-- Slow things down a bit to ensure that no messages as lost.
|
||||
-- Physical MIDI is sent at 31.25kBaud.
|
||||
-- Every message is sent as 10bit message on the wire,
|
||||
-- so every MIDI byte needs 320usec.
|
||||
ARDOUR.LuaAPI.usleep (400 * parser:buffer_size ())
|
||||
end
|
||||
end
|
||||
end
|
||||
|
||||
-- show progress dialog
|
||||
local pdialog = LuaDialog.ProgressWindow ("MIDI Tuning", true)
|
||||
pdialog:progress (0, "Tuning");
|
||||
|
||||
-- MIDI Tuning message
|
||||
-- http://technogems.blogspot.com/2018/07/using-midi-tuning-specification-mts.html
|
||||
-- http://www.ludovico.net/download/materiale_didattico/midi/08_midi_tuning.pdf
|
||||
local syx = string.char (
|
||||
0xf0, 0x7e, -- non-realtime sysex
|
||||
0x00, -- target-id
|
||||
0x08, 0x01, -- tuning, bulk dump reply
|
||||
0x00, -- tuning program number 0 to 127 in hexadecimal
|
||||
-- 16 chars name (zero padded)
|
||||
0x53, 0x63, 0x6C, 0x2D, 0x4D, 0x54, 0x53, 0x00, -- Scl-MTS
|
||||
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
|
||||
)
|
||||
tx_midi (syx, 22, 1)
|
||||
|
||||
-- iterate over MIDI notes
|
||||
for nn = 0, 127 do
|
||||
if pdialog:canceled () then break end
|
||||
|
||||
-- calculate the frequency of the note
|
||||
local fq = ref_freq * 2 ^ ((nn - 69) / 12)
|
||||
|
||||
-- and then convert this frequency to the MIDI note number (and cent offset)
|
||||
local base, cent = freq_to_mts (fq)
|
||||
|
||||
-- MTS uses two MIDI bytes (2^14) for cents
|
||||
local cc = math.floor (163.83 * cent + 0.5) | 0
|
||||
local cent_msb = (cc >> 7) & 127
|
||||
local cent_lsb = cc & 127
|
||||
|
||||
--[[
|
||||
print (string.format ("MIDI-Note %3d | Freq: %8.2f Hz = note: %3d + %6.3f ct (0x%02x 0x%02x 0x%02x)",
|
||||
nn, fq, base, cent, base, cent_msb, cent_lsb))
|
||||
--]]
|
||||
|
||||
if (base < 0 or base > 127) then
|
||||
if base < 0 then
|
||||
base = 0
|
||||
else
|
||||
base = 127
|
||||
end
|
||||
cent_msb = 0
|
||||
cent_lsb = 0
|
||||
end
|
||||
|
||||
local syx = string.char (
|
||||
base, -- semitone (MIDI note number to retune to, unit is 100 cents)
|
||||
cent_msb, -- MSB of fractional part (1/128 semitone = 100/128 cents = .78125 cent units)
|
||||
cent_lsb, -- LSB of fractional part (1/16384 semitone = 100/16384 cents = .0061 cent units)
|
||||
0xf7
|
||||
)
|
||||
tx_midi (syx, 3, 0)
|
||||
|
||||
-- show progress
|
||||
pdialog:progress (nn / 127, string.format ("Note %d freq: %.2f (%d + %d)", nn, fq, base, cc))
|
||||
if pdialog:canceled () then break end
|
||||
|
||||
::continue::
|
||||
end
|
||||
|
||||
if not pdialog:canceled () then
|
||||
tx_midi (string.char ((checksum & 127), 0xf7), 2, 2)
|
||||
end
|
||||
|
||||
-- hide modal progress dialog and destroy it
|
||||
pdialog:done ();
|
||||
|
||||
tx = nil
|
||||
parser = nil
|
||||
collectgarbage () -- and release any references
|
||||
|
||||
--dump:close ()
|
||||
|
||||
end end
|
||||
|
||||
-- simple icon
|
||||
function icon (params) return function (ctx, width, height, fg)
|
||||
ctx:set_source_rgba (ARDOUR.LuaAPI.color_to_rgba (fg))
|
||||
local txt = Cairo.PangoLayout (ctx, "ArdourMono ".. math.ceil(math.min (width, height) * .45) .. "px")
|
||||
txt:set_text ("MTS")
|
||||
local tw, th = txt:get_pixel_size ()
|
||||
ctx:move_to (.5 * (width - tw), .5 * (height - th))
|
||||
txt:show_in_cairo_context (ctx)
|
||||
end end
|
||||
Loading…
Reference in New Issue