Implement buffering of visualizer samples read from the fifo

src/Makefile.am

@@ -25,6 +25,7 @@ ncmpcpp_SOURCES = \
 	utility/comparators.cpp \
 	utility/html.cpp \
 	utility/option_parser.cpp \
+	utility/sample_buffer.cpp \
 	utility/string.cpp \
 	utility/type_conversions.cpp \
 	utility/wide_string.cpp \
@@ -90,6 +91,7 @@ noinst_HEADERS = \
 	utility/html.h \
 	utility/option_parser.h \
 	utility/readline.h \
+	utility/sample_buffer.h \
 	utility/scoped_value.h \
 	utility/storage_kind.h \
 	utility/shared_resource.h \

src/lastfm_service.h

@@ -58,6 +58,8 @@ struct ArtistInfo : public Service
 	ArtistInfo(std::string artist, std::string lang)
 	: Service({{"artist", artist}, {"lang", lang}}) { }
 
+	virtual ~ArtistInfo() { }
+	
 	virtual const char *name() { return "Artist info"; }
 	
 	virtual void beautifyOutput(NC::Scrollpad &w);

src/screens/visualizer.cpp

@@ -33,6 +33,9 @@
 #include <fcntl.h>
 #include <cassert>
 
+#include <arpa/inet.h>
+#include <sys/socket.h>
+
 #include "global.h"
 #include "settings.h"
 #include "status.h"
@@ -68,6 +71,9 @@ const NC::FormattedColor &toColor(size_t number, size_t max, bool wrap = true)
 
 Visualizer::Visualizer()
 : Screen(NC::Window(0, MainStartY, COLS, MainHeight, "", NC::Color::Default, NC::Border()))
+, m_sample_consumption_rate(5)
+, m_sample_consumption_rate_up_ctr(0)
+, m_sample_consumption_rate_dn_ctr(0)
 #	ifdef HAVE_FFTW3_H
 	,
   DFT_NONZERO_SIZE(1 << Config.visualizer_spectrum_dft_size),
@@ -131,13 +137,6 @@ void Visualizer::update()
 	if (m_fifo < 0)
 		return;
 
-	// PCM in format 44100:16:1 (for mono visualization) and
-	// 44100:16:2 (for stereo visualization) is supported.
-	const int buf_size = sizeof(int16_t)*m_read_samples;
-	ssize_t bytes_read = read(m_fifo, m_temp_sample_buffer.data(), buf_size);
-	if (bytes_read <= 0) // no data available in fifo
-		return;
-
 	if (m_output_id != -1 && Global::Timer - m_timer > Config.visualizer_sync_interval)
 	{
 		Mpd.DisableOutput(m_output_id);
@@ -146,11 +145,18 @@ void Visualizer::update()
 		m_timer = Global::Timer;
 	}
 
+	// PCM in format 44100:16:1 (for mono visualization) and
+	// 44100:16:2 (for stereo visualization) is supported.
+	ssize_t bytes_read = read(m_fifo, m_incoming_samples.data(),
+	                          sizeof(int16_t) * m_incoming_samples.size());
+	if (bytes_read > 0)
+	{
+		const auto begin = m_incoming_samples.begin();
+		const auto end = m_incoming_samples.begin() + bytes_read/sizeof(int16_t);
+
 		if (Config.visualizer_autoscale)
 		{
 			m_auto_scale_multiplier += 1.0/Config.visualizer_fps;
-		const auto begin = m_temp_sample_buffer.begin();
-		const auto end = m_temp_sample_buffer.begin() + bytes_read/sizeof(int16_t);
 			for (auto sample = begin; sample != end; ++sample)
 			{
 				double scale = std::numeric_limits<int16_t>::min();
@@ -172,25 +178,48 @@ void Visualizer::update()
 					*sample = tmp;
 			}
 		}
+		m_buffered_samples.put(begin, end);
+	}
 
+	size_t requested_samples =
+		44100.0 / Config.visualizer_fps * pow(1.1, m_sample_consumption_rate);
+	if (Config.visualizer_in_stereo)
+		requested_samples *= 2;
+
+	Statusbar::printf("Samples: %1%, %2%, %3%", m_buffered_samples.size(),
+	                  requested_samples, m_sample_consumption_rate);
+
+	size_t new_samples = m_buffered_samples.move(requested_samples, m_rendered_samples);
+	if (new_samples == 0)
+		return;
+
+	if (m_buffered_samples.size() > 0)
+	{
+		if (++m_sample_consumption_rate_up_ctr > 8)
+		{
+			m_sample_consumption_rate_up_ctr = 0;
+			++m_sample_consumption_rate;
+		}
+	}
+	else if (m_sample_consumption_rate > 0)
+	{
+		if (++m_sample_consumption_rate_dn_ctr > 2)
 		{
-		// create int8_t pointers for arithmetic
+			m_sample_consumption_rate_dn_ctr = 0;
-		int8_t *const sdata = (int8_t *)m_sample_buffer.data();
+			--m_sample_consumption_rate;
-		int8_t *const temp_sdata = (int8_t *)m_temp_sample_buffer.data();
+		}
-		int8_t *const sdata_end = sdata + buf_size;
+		m_sample_consumption_rate_up_ctr = 0;
-		memmove(sdata, sdata + bytes_read, buf_size - bytes_read);
-		memcpy(sdata_end - bytes_read, temp_sdata, bytes_read);
 	}
 
 	w.clear();
 	if (Config.visualizer_in_stereo)
 	{
-		auto chan_samples = m_read_samples/2;
+		auto chan_samples = m_rendered_samples.size()/2;
 		int16_t buf_left[chan_samples], buf_right[chan_samples];
-		for (size_t i = 0, j = 0; i < m_read_samples; i += 2, ++j)
+		for (size_t i = 0, j = 0; i < m_rendered_samples.size(); i += 2, ++j)
 		{
-			buf_left[j] = m_sample_buffer[i];
+			buf_left[j] = m_rendered_samples[i];
-			buf_right[j] = m_sample_buffer[i+1];
+			buf_right[j] = m_rendered_samples[i+1];
 		}
 		size_t half_height = w.getHeight()/2;
 
@@ -198,14 +227,14 @@ void Visualizer::update()
 	}
 	else
 	{
-		(this->*draw)(m_sample_buffer.data(), m_read_samples, 0, w.getHeight());
+		(this->*draw)(m_rendered_samples.data(), m_rendered_samples.size(), 0, w.getHeight());
 	}
 	w.refresh();
 }
 
 int Visualizer::windowTimeout()
 {
-	if (m_fifo >= 0 && Status::State::player() == MPD::psPlay)
+	if (m_fifo >= 0)// && Status::State::player() == MPD::psPlay)
 		return 1000/Config.visualizer_fps;
 	else
 		return Screen<WindowType>::windowTimeout();
@@ -596,42 +625,51 @@ void Visualizer::GenLogspace()
 
 void Visualizer::InitVisualization()
 {
+	size_t rendered_samples = 0;
 	switch (Config.visualizer_type)
 	{
 	case VisualizerType::Wave:
 		// Guarantee integral amount of samples per column.
-		m_read_samples = ceil(44100.0 / Config.visualizer_fps / w.getWidth());
+		rendered_samples = ceil(44100.0 / Config.visualizer_fps / w.getWidth());
-		m_read_samples *= w.getWidth();
+		rendered_samples *= w.getWidth();
+		// Slow the scolling 10 times to make it watchable.
+		rendered_samples *= 10;
 		draw = &Visualizer::DrawSoundWave;
 		drawStereo = &Visualizer::DrawSoundWaveStereo;
 		break;
 	case VisualizerType::WaveFilled:
 		// Guarantee integral amount of samples per column.
-		m_read_samples = ceil(44100.0 / Config.visualizer_fps / w.getWidth());
+		rendered_samples = ceil(44100.0 / Config.visualizer_fps / w.getWidth());
-		m_read_samples *= w.getWidth();
+		rendered_samples *= w.getWidth();
+		// Slow the scolling 10 times to make it watchable.
+		rendered_samples *= 10;
 		draw = &Visualizer::DrawSoundWaveFill;
 		drawStereo = &Visualizer::DrawSoundWaveFillStereo;
 		break;
 #	ifdef HAVE_FFTW3_H
 	case VisualizerType::Spectrum:
-		m_read_samples = DFT_NONZERO_SIZE;
+		rendered_samples = DFT_NONZERO_SIZE;
 		draw = &Visualizer::DrawFrequencySpectrum;
 		drawStereo = &Visualizer::DrawFrequencySpectrumStereo;
 		break;
 #	endif // HAVE_FFTW3_H
 	case VisualizerType::Ellipse:
 		// Keep constant amount of samples on the screen regardless of fps.
-		m_read_samples = 44100 / 25;
+		rendered_samples = 44100 / 30;
 		draw = &Visualizer::DrawSoundEllipse;
 		drawStereo = &Visualizer::DrawSoundEllipseStereo;
 		break;
 	}
 	if (Config.visualizer_in_stereo)
-		m_read_samples *= 2;
+		rendered_samples *= 2;
-	m_sample_buffer.resize(m_read_samples);
+	m_rendered_samples.resize(rendered_samples);
-	m_temp_sample_buffer.resize(m_read_samples);
+
-	std::fill(m_sample_buffer.begin(), m_sample_buffer.end(), 0);
+	// Keep 500ms worth of samples in the incoming buffer.
-	std::fill(m_temp_sample_buffer.begin(), m_temp_sample_buffer.end(), 0);
+	size_t buffered_samples = 44100.0 / 2;
+	if (Config.visualizer_in_stereo)
+		buffered_samples *= 2;
+	m_incoming_samples.resize(buffered_samples);
+	m_buffered_samples.resize(buffered_samples);
 }
 
 /**********************************************************************/
@@ -639,7 +677,7 @@ void Visualizer::InitVisualization()
 void Visualizer::Clear()
 {
 	w.clear();
-	std::fill(m_sample_buffer.begin(), m_sample_buffer.end(), 0);
+	std::fill(m_rendered_samples.begin(), m_rendered_samples.end(), 0);
 }
 
 void Visualizer::ToggleVisualizationType()
@@ -671,6 +709,38 @@ void Visualizer::ToggleVisualizationType()
 
 void Visualizer::SetFD()
 {
+/*
+	if (m_fifo >= 0)
+		return;
+
+	sockaddr_in si_me;
+
+	if ((m_fifo = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP)) < 0)
+	{
+		Statusbar::printf("socket failed: %s", strerror(errno));
+		return;
+	}
+
+	int flags = fcntl(m_fifo, F_GETFL, 0);
+	fcntl(m_fifo, F_SETFL, flags | O_NONBLOCK);
+
+	memset(&si_me, 0, sizeof(si_me));
+
+	si_me.sin_family = AF_INET;
+	si_me.sin_port = htons(5555);
+	si_me.sin_addr.s_addr = INADDR_ANY;
+
+	// bind socket to port
+	if (bind(m_fifo, (sockaddr *)&si_me, sizeof(si_me)) < 0)
+	{
+		Statusbar::printf("bind failed: %s", strerror(errno));
+		return;
+
+	}
+
+	return;
+*/
+
 	if (m_fifo < 0 && (m_fifo = open(Config.visualizer_fifo_path.c_str(), O_RDONLY | O_NONBLOCK)) < 0)
 		Statusbar::printf("Couldn't open \"%1%\" for reading PCM data: %2%",
 			Config.visualizer_fifo_path, strerror(errno)
@@ -679,6 +749,8 @@ void Visualizer::SetFD()
 
 void Visualizer::ResetFD()
 {
+	if (m_fifo > 0)
+		close(m_fifo);
 	m_fifo = -1;
 }
 

src/screens/visualizer.h

@@ -29,11 +29,13 @@
 #include "curses/window.h"
 #include "interfaces.h"
 #include "screens/screen.h"
+#include "utility/sample_buffer.h"
 
 #ifdef HAVE_FFTW3_H
 # include <fftw3.h>
 #endif
 
+
 struct Visualizer: Screen<NC::Window>, Tabbable
 {
 	Visualizer();
@@ -86,9 +88,14 @@ private:
 	boost::posix_time::ptime m_timer;
 
 	int m_fifo;
-	size_t m_read_samples;
+
-	std::vector<int16_t> m_sample_buffer;
+	std::vector<int16_t> m_rendered_samples;
-	std::vector<int16_t> m_temp_sample_buffer;
+	std::vector<int16_t> m_incoming_samples;
+	SampleBuffer m_buffered_samples;
+	size_t m_sample_consumption_rate;
+	size_t m_sample_consumption_rate_up_ctr;
+	size_t m_sample_consumption_rate_dn_ctr;
+
 	double m_auto_scale_multiplier;
 #	ifdef HAVE_FFTW3_H
 	size_t m_fftw_results;

src/utility/sample_buffer.cpp

@@ -0,0 +1,93 @@
+/***************************************************************************
+ *   Copyright (C) 2008-2017 by Andrzej Rybczak                            *
+ *   electricityispower@gmail.com                                          *
+ *                                                                         *
+ *   This program is free software; you can redistribute it and/or modify  *
+ *   it under the terms of the GNU General Public License as published by  *
+ *   the Free Software Foundation; either version 2 of the License, or     *
+ *   (at your option) any later version.                                   *
+ *                                                                         *
+ *   This program is distributed in the hope that it will be useful,       *
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
+ *   GNU General Public License for more details.                          *
+ *                                                                         *
+ *   You should have received a copy of the GNU General Public License     *
+ *   along with this program; if not, write to the                         *
+ *   Free Software Foundation, Inc.,                                       *
+ *   51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.              *
+ ***************************************************************************/
+
+#include <stdexcept>
+
+#include "utility/sample_buffer.h"
+
+void SampleBuffer::put(SampleBuffer::Iterator begin, SampleBuffer::Iterator end)
+{
+	size_t elems = end - begin;
+	if (elems > m_buffer.size())
+		throw std::out_of_range("Size of the buffer is smaller than the amount of elements");
+
+	size_t free_elems = m_buffer.size() - m_offset;
+	if (elems > free_elems)
+	{
+		size_t to_remove = elems - free_elems;
+		std::copy(m_buffer.begin() + to_remove, m_buffer.end() - free_elems,
+		          m_buffer.begin());
+		m_offset -= to_remove;
+	}
+	std::copy(begin, end, m_buffer.begin() + m_offset);
+	m_offset += elems;
+}
+
+size_t SampleBuffer::move(size_t elems, std::vector<int16_t> &dest)
+{
+	if (m_offset == 0)
+		return 0;
+
+	// If the amount of requested samples is bigger than available, return only
+	// available.
+	if (elems > m_offset)
+		elems = m_offset;
+
+	if (elems >= dest.size())
+	{
+		// If dest is smaller than the available amount of samples, discard the
+		// ones that come first.
+		size_t elems_lost = elems - dest.size();
+		std::copy(m_buffer.begin() + elems_lost, m_buffer.begin() + elems, dest.begin());
+	}
+	else
+	{
+		// Copy samples to the destination buffer.
+		std::copy(dest.begin() + elems, dest.end(), dest.begin());
+		std::copy(m_buffer.begin(), m_buffer.begin() + elems, dest.end() - elems);
+	}
+
+	// Remove them from the internal buffer.
+	std::copy(m_buffer.begin() + elems, m_buffer.begin() + m_offset, m_buffer.begin());
+	m_offset -= elems;
+
+	return elems;
+}
+
+void SampleBuffer::resize(size_t n)
+{
+	m_buffer.resize(n);
+	clear();
+}
+
+void SampleBuffer::clear()
+{
+	m_offset = 0;
+}
+
+size_t SampleBuffer::size() const
+{
+	return m_offset;
+}
+
+const std::vector<int16_t> &SampleBuffer::buffer() const
+{
+	return m_buffer;
+}

src/utility/sample_buffer.h

@@ -0,0 +1,47 @@
+/***************************************************************************
+ *   Copyright (C) 2008-2017 by Andrzej Rybczak                            *
+ *   electricityispower@gmail.com                                          *
+ *                                                                         *
+ *   This program is free software; you can redistribute it and/or modify  *
+ *   it under the terms of the GNU General Public License as published by  *
+ *   the Free Software Foundation; either version 2 of the License, or     *
+ *   (at your option) any later version.                                   *
+ *                                                                         *
+ *   This program is distributed in the hope that it will be useful,       *
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
+ *   GNU General Public License for more details.                          *
+ *                                                                         *
+ *   You should have received a copy of the GNU General Public License     *
+ *   along with this program; if not, write to the                         *
+ *   Free Software Foundation, Inc.,                                       *
+ *   51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.              *
+ ***************************************************************************/
+
+#ifndef NCMPCPP_SAMPLE_BUFFER_H
+#define NCMPCPP_SAMPLE_BUFFER_H
+
+#include <cstdint>
+#include <vector>
+
+struct SampleBuffer
+{
+	typedef std::vector<int16_t>::iterator Iterator;
+
+	SampleBuffer() : m_offset(0) { }
+
+	void put(Iterator begin, Iterator end);
+	size_t move(size_t elems, std::vector<int16_t> &dest);
+
+	void resize(size_t n);
+	void clear();
+
+	size_t size() const;
+	const std::vector<int16_t> &buffer() const;
+
+private:
+	size_t m_offset;
+	std::vector<int16_t> m_buffer;
+};
+
+#endif // NCMPCPP_SAMPLE_BUFFER_H