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livetrax/scripts/spectrogram.lua

333 lines
9.2 KiB
Lua

ardour {
["type"] = "dsp",
name = "Inline Spectrogram",
category = "Visualization",
license = "GPLv2",
author = "Robin Gareus",
email = "robin@gareus.org",
site = "http://gareus.org",
description = [[An Example DSP Plugin to display a spectrom on the mixer strip]]
}
-- 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
function dsp_params ()
return
{
{ ["type"] = "input", name = "Logscale", min = 0, max = 1, default = 0, toggled = true },
{ ["type"] = "input", name = "1/f scale", min = 0, max = 1, default = 1, toggled = true },
{ ["type"] = "input", name = "FFT Size", min = 0, max = 4, default = 3, enum = true, scalepoints =
{
["512"] = 0,
["1024"] = 1,
["2048"] = 2,
["4096"] = 3,
["8192"] = 4,
}
},
{ ["type"] = "input", name = "Height (Aspect)", min = 0, max = 3, default = 1, enum = true, scalepoints =
{
["Min"] = 0,
["16:10"] = 1,
["1:1"] = 2,
["Max"] = 3
}
},
{ ["type"] = "input", name = "Range", min = 20, max = 160, default = 60, unit="dB"},
{ ["type"] = "input", name = "Offset", min = -40, max = 40, default = 0, unit="dB"},
}
end
-- a C memory area.
-- It needs to be in global scope.
-- When the variable is set to nil, the allocated memory is free()ed.
-- the memory can be interpeted as float* for use in DSP, or read/write
-- to a C++ Ringbuffer instance.
-- http://manual.ardour.org/lua-scripting/class_reference/#ARDOUR:DSP:DspShm
local cmem = nil
function dsp_init (rate)
-- global variables (DSP part only)
dpy_hz = rate / 25
dpy_wr = 0
-- create a ringbuffer to hold (float) audio-data
-- http://manual.ardour.org/lua-scripting/class_reference/#PBD:RingBufferF
rb = PBD.RingBufferF (2 * rate)
-- allocate memory, local mix buffer
cmem = ARDOUR.DSP.DspShm (8192)
-- create a table of objects to share with the GUI
local tbl = {}
tbl['rb'] = rb;
tbl['samplerate'] = rate
-- "self" is a special DSP variable referring
-- to the plugin instance itself.
--
-- "table()" is-a http://manual.ardour.org/lua-scripting/class_reference/#ARDOUR.LuaTableRef
-- which allows to store/retrieve lua-tables to share them other interpreters
self:table ():set (tbl);
end
-- "dsp_runmap" uses Ardour's internal processor API, eqivalent to
-- 'connect_and_run()". There is no overhead (mapping, translating buffers).
-- The lua implementation is responsible to map all the buffers directly.
function dsp_runmap (bufs, in_map, out_map, n_samples, offset)
-- here we sum all audio input channels channels and then copy the data to a ringbuffer
-- for the GUI to process later
local audio_ins = in_map:count (): n_audio () -- number of audio input buffers
local ccnt = 0 -- processed channel count
local mem = cmem:to_float(0) -- a "FloatArray", float* for direct C API usage from the previously allocated buffer
for c = 1,audio_ins do
-- see http://manual.ardour.org/lua-scripting/class_reference/#ARDOUR:ChanMapping
-- Note: lua starts counting at 1, ardour's ChanMapping::get() at 0
local ib = in_map:get (ARDOUR.DataType ("audio"), c - 1) -- get index of mapped input buffer
local ob = out_map:get (ARDOUR.DataType ("audio"), c - 1) -- get index of mapped output buffer
-- check if the input is connected to a buffer
if (ib ~= ARDOUR.ChanMapping.Invalid) then
-- http://manual.ardour.org/lua-scripting/class_reference/#ARDOUR:AudioBuffer
-- http://manual.ardour.org/lua-scripting/class_reference/#ARDOUR:DSP
if c == 1 then
-- first channel, copy as-is
ARDOUR.DSP.copy_vector (mem, bufs:get_audio (ib):data (offset), n_samples)
else
-- all other channels, add to existing data.
ARDOUR.DSP.mix_buffers_no_gain (mem, bufs:get_audio (ib):data (offset), n_samples)
end
ccnt = ccnt + 1;
-- copy data to output (if not processing in-place)
if (ob ~= ARDOUR.ChanMapping.Invalid and ib ~= ob) then
ARDOUR.DSP.copy_vector (bufs:get_audio (ob):data (offset), bufs:get_audio (ib):data (offset), n_samples)
end
end
end
-- Clear unconnected output buffers.
-- In case we're processing in-place some buffers may be identical,
-- so this must be done *after processing*.
for c = 1,audio_ins do
local ib = in_map:get (ARDOUR.DataType ("audio"), c - 1)
local ob = out_map:get (ARDOUR.DataType ("audio"), c - 1)
if (ib == ARDOUR.ChanMapping.Invalid and ob ~= ARDOUR.ChanMapping.Invalid) then
bufs:get_audio (ob):silence (n_samples, offset)
end
end
-- Normalize gain (1 / channel-count)
if ccnt > 1 then
ARDOUR.DSP.apply_gain_to_buffer (mem, n_samples, 1 / ccnt)
end
-- if no channels were processed, feed silence.
if ccnt == 0 then
ARDOUR.DSP.memset (mem, 0, n_samples)
end
-- write data to the ringbuffer
-- http://manual.ardour.org/lua-scripting/class_reference/#PBD:RingBufferF
rb:write (mem, n_samples)
-- emit QueueDraw every FPS
-- TODO: call every FFT window-size worth of samples, at most every FPS
dpy_wr = dpy_wr + n_samples
if (dpy_wr > dpy_hz) then
dpy_wr = dpy_wr % dpy_hz
self:queue_draw ()
end
end
----------------------------------------------------------------
-- GUI
local fft = nil
local read_ptr = 0
local line = 0
local img = nil
local fft_size = 0
local last_log = false
function render_inline (ctx, w, max_h)
local ctrl = CtrlPorts:array () -- get control port array (read/write)
local tbl = self:table ():get () -- get shared memory table
local rate = tbl['samplerate']
if not cmem then
cmem = ARDOUR.DSP.DspShm (0)
end
-- get settings
local logscale = ctrl[1] or 0; logscale = logscale > 0 -- x-axis logscale
local pink = ctrl[2] or 0; pink = pink > 0 -- 1/f scale
local fftsizeenum = ctrl[3] or 3 -- fft-size enum
local hmode = ctrl[4] or 1 -- height mode enum
local dbrange = ctrl[5] or 60
local gaindb = ctrl[6] or 0
local fftsize
if fftsizeenum == 0 then fftsize = 512
elseif fftsizeenum == 1 then fftsize = 1024
elseif fftsizeenum == 2 then fftsize = 2048
elseif fftsizeenum == 4 then fftsize = 8192
else fftsize = 4096
end
if fftsize ~= fft_size then
fft_size = fftsize
fft = nil
end
if dbrange < 20 then dbrange = 20; end
if dbrange > 160 then dbrange = 160; end
if gaindb < -40 then dbrange = -40; end
if gaindb > 40 then dbrange = 40; end
if not fft then
fft = ARDOUR.DSP.FFTSpectrum (fft_size, rate)
cmem:allocate (fft_size)
end
if last_log ~= logscale then
last_log = logscale
img = nil
line = 0
end
-- calc height
if hmode == 0 then
h = math.ceil (w * 10 / 16)
if (h > 44) then
h = 44
end
elseif (hmode == 2) then
h = w
elseif (hmode == 3) then
h = max_h
else
h = math.ceil (w * 10 / 16)
end
if (h > max_h) then
h = max_h
end
-- re-create image surface
if not img or img:get_width() ~= w or img:get_height () ~= h then
img = Cairo.ImageSurface (Cairo.Format.ARGB32, w, h)
line = 0
end
local ictx = img:context ()
local bins = fft_size / 2 - 1 -- fft bin count
local bpx = bins / w -- bins per x-pixel (linear)
local fpb = rate / fft_size -- freq-step per bin
local f_e = rate / 2 / fpb -- log-scale exponent
local f_b = w / math.log (fft_size / 2) -- inverse log-scale base
local f_l = math.log (fft_size / rate) * f_b -- inverse logscale lower-bound
local rb = tbl['rb'];
local mem = cmem:to_float (0)
while (rb:read_space() >= fft_size) do
-- process one line / buffer
rb:read (mem, fft_size)
fft:set_data_hann (mem, fft_size, 0)
fft:execute ()
-- draw spectrum
assert (bpx >= 1)
-- scroll
if line == 0 then line = h - 1; else line = line - 1; end
-- clear this line
ictx:set_source_rgba (0, 0, 0, 1)
ictx:rectangle (0, line, w, 1)
ictx:fill ()
for x = 0, w - 1 do
local pk = 0
local b0, b1
if logscale then
-- 20 .. 20k
b0 = math.floor (f_e ^ (x / w))
b1 = math.floor (f_e ^ ((x + 1) / w))
else
b0 = math.floor (x * bpx)
b1 = math.floor ((x + 1) * bpx)
end
if b1 >= b0 and b1 <= bins and b0 >= 0 then
for i = b0, b1 do
local level = gaindb + fft:power_at_bin (i, pink and i or 1) -- pink ? i : 1
if level > -dbrange then
local p = (dbrange + level) / dbrange
if p > pk then pk = p; end
end
end
end
if pk > 0.0 then
if pk > 1.0 then pk = 1.0; end
ictx:set_source_rgba (ARDOUR.LuaAPI.hsla_to_rgba (.70 - .72 * pk, .9, .3 + pk * .4));
ictx:rectangle (x, line, 1, 1)
ictx:fill ()
end
end
end
-- copy image surface
if line == 0 then
img:set_as_source (ctx, 0, 0)
ctx:rectangle (0, 0, w, h)
ctx:fill ()
else
local yp = h - line - 1;
img:set_as_source (ctx, 0, yp)
ctx:rectangle (0, yp, w, line)
ctx:fill ()
img:set_as_source (ctx, 0, -line)
ctx:rectangle (0, 0, w, yp)
ctx:fill ()
end
-- draw grid on top
function x_at_freq (f)
if logscale then
return f_l + f_b * math.log (f)
else
return 2 * w * f / rate;
end
end
function grid_freq (f)
-- draw vertical grid line
local x = .5 + math.floor (x_at_freq (f))
ctx:move_to (x, 0)
ctx:line_to (x, h)
ctx:stroke ()
end
-- draw grid on top
local dash3 = C.DoubleVector ()
dash3:add ({1, 3})
ctx:set_line_width (1.0)
ctx:set_dash (dash3, 2) -- dotted line
ctx:set_source_rgba (.5, .5, .5, .8)
grid_freq (100)
grid_freq (1000)
grid_freq (10000)
ctx:unset_dash ()
return {w, h}
end