1 files changed, 281 insertions, 0 deletions
diff --git a/src/wx/audio_plot.cc b/src/wx/audio_plot.cc
new file mode 100644
index 000000000..7ed792351
--- /dev/null
+++ b/src/wx/audio_plot.cc
@@ -0,0 +1,281 @@
+/*
+    Copyright (C) 2013 Carl Hetherington <cth@carlh.net>
+
+    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., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+*/
+
+#include <iostream>
+#include <boost/bind.hpp>
+#include <wx/graphics.h>
+#include "audio_plot.h"
+#include "lib/audio_decoder.h"
+#include "lib/audio_analysis.h"
+#include "wx/wx_util.h"
+
+using std::cout;
+using std::vector;
+using std::list;
+using std::max;
+using std::min;
+using boost::bind;
+using boost::shared_ptr;
+
+int const AudioPlot::_minimum = -70;
+int const AudioPlot::max_smoothing = 128;
+
+AudioPlot::AudioPlot (wxWindow* parent)
+	: wxPanel (parent, wxID_ANY, wxDefaultPosition, wxDefaultSize, wxFULL_REPAINT_ON_RESIZE)
+	, _gain (0)
+	, _smoothing (max_smoothing / 2)
+	, _message (_("Please wait; audio is being analysed..."))
+{
+#ifndef __WXOSX__	
+	SetDoubleBuffered (true);
+#endif	
+
+	for (int i = 0; i < MAX_AUDIO_CHANNELS; ++i) {
+		_channel_visible[i] = false;
+	}
+
+	for (int i = 0; i < AudioPoint::COUNT; ++i) {
+		_type_visible[i] = false;
+	}
+
+	_colours.push_back (wxColour (	0,   0,	  0));
+	_colours.push_back (wxColour (255,   0,	  0));
+	_colours.push_back (wxColour (	0, 255,	  0));
+	_colours.push_back (wxColour (139,   0, 204));
+	_colours.push_back (wxColour (	0,   0, 255));
+	_colours.push_back (wxColour (100, 100, 100));
+	
+	Bind (wxEVT_PAINT, boost::bind (&AudioPlot::paint, this));
+	
+	SetMinSize (wxSize (640, 512));
+}
+
+void
+AudioPlot::set_analysis (shared_ptr<AudioAnalysis> a)
+{
+	_analysis = a;
+
+	for (int i = 0; i < MAX_AUDIO_CHANNELS; ++i) {
+		_channel_visible[i] = false;
+	}
+
+	for (int i = 0; i < AudioPoint::COUNT; ++i) {
+		_type_visible[i] = false;
+	}
+	
+	Refresh ();
+}
+
+void
+AudioPlot::set_channel_visible (int c, bool v)
+{
+	_channel_visible[c] = v;
+	Refresh ();
+}
+
+void
+AudioPlot::set_type_visible (int t, bool v)
+{
+	_type_visible[t] = v;
+	Refresh ();
+}
+
+void
+AudioPlot::set_message (wxString s)
+{
+	_message = s;
+	Refresh ();
+}
+
+void
+AudioPlot::paint ()
+{
+	wxPaintDC dc (this);
+
+	wxGraphicsContext* gc = wxGraphicsContext::Create (dc);
+	if (!gc) {
+		return;
+	}
+
+	if (!_analysis || _analysis->channels() == 0) {
+		gc->SetFont (gc->CreateFont (*wxNORMAL_FONT));
+		gc->DrawText (_message, 32, 32);
+		return;
+	}
+
+	wxGraphicsPath grid = gc->CreatePath ();
+	gc->SetFont (gc->CreateFont (*wxSMALL_FONT));
+	wxDouble db_label_height;
+	wxDouble db_label_descent;
+	wxDouble db_label_leading;
+	gc->GetTextExtent (wxT ("-80dB"), &_db_label_width, &db_label_height, &db_label_descent, &db_label_leading);
+
+	_db_label_width += 8;
+	
+	int const data_width = GetSize().GetWidth() - _db_label_width;
+	/* Assume all channels have the same number of points */
+	_x_scale = data_width / float (_analysis->points (0));
+	_height = GetSize().GetHeight ();
+	_y_origin = 32;
+	_y_scale = (_height - _y_origin) / -_minimum;
+
+	for (int i = _minimum; i <= 0; i += 10) {
+		int const y = (_height - (i - _minimum) * _y_scale) - _y_origin;
+		grid.MoveToPoint (_db_label_width - 4, y);
+		grid.AddLineToPoint (_db_label_width + data_width, y);
+		gc->DrawText (std_to_wx (String::compose ("%1dB", i)), 0, y - (db_label_height / 2));
+	}
+
+	gc->SetPen (*wxLIGHT_GREY_PEN);
+	gc->StrokePath (grid);
+
+	gc->DrawText (_("Time"), data_width, _height - _y_origin + db_label_height / 2);
+
+	
+	if (_type_visible[AudioPoint::PEAK]) {
+		for (int c = 0; c < MAX_AUDIO_CHANNELS; ++c) {
+			wxGraphicsPath p = gc->CreatePath ();
+			if (_channel_visible[c] && c < _analysis->channels()) {
+				plot_peak (p, c);
+			}
+			wxColour const col = _colours[c];
+			gc->SetPen (*wxThePenList->FindOrCreatePen (wxColour (col.Red(), col.Green(), col.Blue(), col.Alpha() / 2), 1, wxPENSTYLE_SOLID));
+			gc->StrokePath (p);
+		}
+	}
+
+	if (_type_visible[AudioPoint::RMS]) {
+		for (int c = 0; c < MAX_AUDIO_CHANNELS; ++c) {
+			wxGraphicsPath p = gc->CreatePath ();
+			if (_channel_visible[c] && c < _analysis->channels()) {
+				plot_rms (p, c);
+			}
+			wxColour const col = _colours[c];
+			gc->SetPen (*wxThePenList->FindOrCreatePen (col, 1, wxPENSTYLE_SOLID));
+			gc->StrokePath (p);
+		}
+	}
+
+	wxGraphicsPath axes = gc->CreatePath ();
+	axes.MoveToPoint (_db_label_width, 0);
+	axes.AddLineToPoint (_db_label_width, _height - _y_origin);
+	axes.AddLineToPoint (_db_label_width + data_width, _height - _y_origin);
+	gc->SetPen (*wxBLACK_PEN);
+	gc->StrokePath (axes);
+
+	delete gc;
+}
+
+float
+AudioPlot::y_for_linear (float p) const
+{
+	return _height - (20 * log10(p) - _minimum + _gain) * _y_scale - _y_origin;
+}
+
+void
+AudioPlot::plot_peak (wxGraphicsPath& path, int channel) const
+{
+	if (_analysis->points (channel) == 0) {
+		return;
+	}
+	
+	path.MoveToPoint (_db_label_width, y_for_linear (_analysis->get_point(channel, 0)[AudioPoint::PEAK]));
+
+	float peak = 0;
+	int const N = _analysis->points(channel);
+	for (int i = 0; i < N; ++i) {
+		float const p = _analysis->get_point(channel, i)[AudioPoint::PEAK];
+		peak -= 0.01f * (1 - log10 (_smoothing) / log10 (max_smoothing));
+		if (p > peak) {
+			peak = p;
+		} else if (peak < 0) {
+			peak = 0;
+		}
+		
+		path.AddLineToPoint (_db_label_width + i * _x_scale, y_for_linear (peak));
+	}
+}
+
+void
+AudioPlot::plot_rms (wxGraphicsPath& path, int channel) const
+{
+	if (_analysis->points (channel) == 0) {
+		return;
+	}
+	
+	path.MoveToPoint (_db_label_width, y_for_linear (_analysis->get_point(channel, 0)[AudioPoint::RMS]));
+
+	list<float> smoothing;
+
+	int const N = _analysis->points(channel);
+
+	float const first = _analysis->get_point(channel, 0)[AudioPoint::RMS];
+	float const last = _analysis->get_point(channel, N - 1)[AudioPoint::RMS];
+
+	int const before = _smoothing / 2;
+	int const after = _smoothing - before;
+	
+	/* Pre-load the smoothing list */
+	for (int i = 0; i < before; ++i) {
+		smoothing.push_back (first);
+	}
+	for (int i = 0; i < after; ++i) {
+		if (i < N) {
+			smoothing.push_back (_analysis->get_point(channel, i)[AudioPoint::RMS]);
+		} else {
+			smoothing.push_back (last);
+		}
+	}
+	
+	for (int i = 0; i < N; ++i) {
+
+		int const next_for_window = i + after;
+
+		if (next_for_window < N) {
+			smoothing.push_back (_analysis->get_point(channel, i)[AudioPoint::RMS]);
+		} else {
+			smoothing.push_back (last);
+		}
+
+		smoothing.pop_front ();
+
+		float p = 0;
+		for (list<float>::const_iterator j = smoothing.begin(); j != smoothing.end(); ++j) {
+			p += pow (*j, 2);
+		}
+
+		p = sqrt (p / smoothing.size ());
+
+		path.AddLineToPoint (_db_label_width + i * _x_scale, y_for_linear (p));
+	}
+}
+
+void
+AudioPlot::set_gain (float g)
+{
+	_gain = g;
+	Refresh ();
+}
+
+void
+AudioPlot::set_smoothing (int s)
+{
+	_smoothing = s;
+	Refresh ();
+}