update lua-scripts:

* add an inline spectrum display
* fix re-init HP/LP and Biquad
* add some comments, labels etc

1 files changed, 296 insertions, 0 deletions

diff --git a/scripts/spectrogram.lua b/scripts/spectrogram.lua
new file mode 100644
index 0000000..94ae043
--- /dev/null
+++ b/scripts/spectrogram.lua
@@ -0,0 +1,296 @@
+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
+
+function dsp_init (rate)
+	-- global variables (DSP part only)
+	samplerate = rate
+	bufsiz = 2 * rate
+	dpy_hz = rate / 25
+	dpy_wr = 0
+end
+
+function dsp_configure (ins, outs)
+	-- store configuration in global variable
+	audio_ins = ins:n_audio ()
+	-- allocate shared memory area, ringbuffer between DSP/GUI
+	self:shmem ():allocate (4 + bufsiz)
+	self:shmem ():clear ()
+	self:shmem ():atomic_set_int (0, 0)
+	local cfg = self:shmem ():to_int (1):array ()
+	cfg[1] = samplerate
+	cfg[2] = bufsiz
+end
+
+function dsp_runmap (bufs, in_map, out_map, n_samples, offset)
+	local shmem = self:shmem ()
+	local write_ptr = shmem:atomic_get_int (0)
+
+	-- sum channels, copy to ringbuffer
+	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 cannel
+		local ob = out_map:get (ARDOUR.DataType ("audio"), c - 1) -- get id of mapped output buffer for given cannel
+		if (ib ~= ARDOUR.ChanMapping.Invalid) then
+			-- check ringbuffer wrap-around
+			if (write_ptr + n_samples < bufsiz) then
+				if c == 1 then
+					ARDOUR.DSP.copy_vector (shmem:to_float (4 + write_ptr), bufs:get_audio (ib):data (offset), n_samples)
+				else
+					ARDOUR.DSP.mix_buffers_no_gain (shmem:to_float (4 + write_ptr), bufs:get_audio (ib):data (offset), n_samples)
+				end
+			else
+				local w0 = bufsiz - write_ptr
+				if c == 1 then
+					ARDOUR.DSP.copy_vector (shmem:to_float (4 + write_ptr), bufs:get_audio (ib):data (offset), w0)
+					ARDOUR.DSP.copy_vector (shmem:to_float (4)            , bufs:get_audio (ib):data (offset + w0), n_samples - w0)
+				else
+					ARDOUR.DSP.mix_buffers_no_gain (shmem:to_float (4 + write_ptr), bufs:get_audio (ib):data (offset), w0)
+					ARDOUR.DSP.mix_buffers_no_gain (shmem:to_float (4)            , bufs:get_audio (ib):data (offset + w0), n_samples - w0)
+				end
+			end
+			-- 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
+		else
+			-- invalid (unconnnected) input
+			if (write_ptr + n_samples < bufsiz) then
+				ARDOUR.DSP.memset (shmem:to_float (4 + write_ptr), 0, n_samples)
+			else
+				local w0 = bufsiz - write_ptr
+				ARDOUR.DSP.memset (shmem:to_float (4 + write_ptr), 0, w0)
+				ARDOUR.DSP.memset (shmem:to_float (4)            , 0, n_samples - w0)
+			end
+		end
+	end
+
+	-- normalize  1 / channel-count
+	if audio_ins > 1 then
+		if (write_ptr + n_samples < bufsiz) then
+			ARDOUR.DSP.apply_gain_to_buffer (shmem:to_float (4 + write_ptr), n_samples, 1 / audio_ins)
+		else
+			local w0 = bufsiz - write_ptr
+			ARDOUR.DSP.apply_gain_to_buffer (shmem:to_float (4 + write_ptr), w0, 1 / audio_ins)
+			ARDOUR.DSP.apply_gain_to_buffer (shmem:to_float (4)            , n_samples - w0, 1 / audio_ins)
+		end
+	end
+
+	-- clear unconnected inplace buffers
+	for c = 1,audio_ins do
+		local ib = in_map:get (ARDOUR.DataType ("audio"), c - 1) -- get id of mapped input buffer for given cannel
+		local ob = out_map:get (ARDOUR.DataType ("audio"), c - 1) -- get id of mapped output buffer for given cannel
+		if (ib == ARDOUR.ChanMapping.Invalid and ob ~= ARDOUR.ChanMapping.Invalid) then
+			bufs:get_audio (ob):silence (n_samples, offset)
+		end
+	end
+
+	write_ptr = (write_ptr + n_samples) % bufsiz
+	shmem:atomic_set_int (0, write_ptr)
+
+	-- emit QueueDraw every FPS
+	-- TODO: call every 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
+
+function render_inline (ctx, w, max_h)
+	local ctrl = CtrlPorts:array () -- get control port array (read/write)
+	local shmem = self:shmem () -- get shared memory region
+	local cfg = shmem:to_int (1):array () -- "cast" into lua-table
+	local rate = cfg[1]
+	local buf_size = cfg[2]
+
+	if buf_size == 0 then
+		return
+	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)
+	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)
+	end
+
+	-- read ring-buffer, analyze
+	local write_ptr = shmem:atomic_get_int (0)
+	local avail = (write_ptr + buf_size - read_ptr) % buf_size
+
+	local ictx = img:context ()
+
+	while (avail >= fft_size) do
+		-- process one line / buffer
+		if read_ptr + fft_size < buf_size then
+			fft:set_data_hann (shmem:to_float (read_ptr + 4), fft_size, 0)
+		else
+			local r0 = buf_size - read_ptr
+			fft:set_data_hann (shmem:to_float (read_ptr + 4), r0, 0)
+			fft:set_data_hann (shmem:to_float (4), fft_size - r0, r0)
+		end
+
+		fft:execute ()
+
+		read_ptr = (read_ptr + fft_size) % buf_size
+		avail = (write_ptr + buf_size - read_ptr ) % buf_size
+
+		-- draw spectrum
+		local bins = fft_size / 2 - 1
+		local bpx = bins / w
+		local fpb = rate / fft_size
+		assert (bpx >= 1)
+
+		local f_e = rate / 2 / fpb
+		-- 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
+
+	return {w, h}
+end