src/visualizer.cpp

   1 /***************************************************************************
   2  *   Copyright (C) 2008-2009 by Andrzej Rybczak                            *
   3  *   electricityispower@gmail.com                                          *
   4  *                                                                         *
   5  *   This program is free software; you can redistribute it and/or modify  *
   6  *   it under the terms of the GNU General Public License as published by  *
   7  *   the Free Software Foundation; either version 2 of the License, or     *
   8  *   (at your option) any later version.                                   *
   9  *                                                                         *
  10  *   This program is distributed in the hope that it will be useful,       *
  11  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  12  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  13  *   GNU General Public License for more details.                          *
  14  *                                                                         *
  15  *   You should have received a copy of the GNU General Public License     *
  16  *   along with this program; if not, write to the                         *
  17  *   Free Software Foundation, Inc.,                                       *
  18  *   51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.              *
  19  ***************************************************************************/
  20
  21 #include "visualizer.h"
  22
  23 #ifdef ENABLE_VISUALIZER
  24
  25 #include "global.h"
  26
  27 #include <cerrno>
  28 #include <cmath>
  29 #include <cstring>
  30 #include <fstream>
  31 #include <fcntl.h>
  32
  33 using Global::myScreen;
  34 using Global::MainStartY;
  35 using Global::MainHeight;
  36
  37 Visualizer *myVisualizer = new Visualizer;
  38
  39 const unsigned Visualizer::Samples = 2048;
  40 #ifdef HAVE_FFTW3_H
  41 const unsigned Visualizer::FFTResults = Samples/2+1;
  42 #endif // HAVE_FFTW3_H
  43
  44 void Visualizer::Init()
  45 {
  46         w = new Window(0, MainStartY, COLS, MainHeight, "", Config.main_color, brNone);
  47         w->SetTimeout(Config.visualizer_fifo_path.empty() ? ncmpcpp_window_timeout : 40 /* this gives us 25 fps */);
  48
  49         ResetFD();
  50 #       ifdef HAVE_FFTW3_H
  51         itsFreqsMagnitude = new unsigned[FFTResults];
  52         itsInput = static_cast<double *>(fftw_malloc(sizeof(double)*Samples));
  53         itsOutput = static_cast<fftw_complex *>(fftw_malloc(sizeof(fftw_complex)*FFTResults));
  54         itsPlan = fftw_plan_dft_r2c_1d(Samples, itsInput, itsOutput, FFTW_ESTIMATE);
  55 #       endif // HAVE_FFTW3_H
  56
  57         isInitialized = 1;
  58 }
  59
  60 void Visualizer::SwitchTo()
  61 {
  62         if (myScreen == this)
  63                 return;
  64
  65         if (!isInitialized)
  66                 Init();
  67
  68         if (hasToBeResized)
  69                 Resize();
  70
  71         myScreen = this;
  72         w->Clear();
  73
  74         SetFD();
  75
  76         Global::RedrawHeader = 1;
  77 }
  78
  79 void Visualizer::Resize()
  80 {
  81         w->Resize(COLS, MainHeight);
  82         w->MoveTo(0, MainStartY);
  83         hasToBeResized = 0;
  84 }
  85
  86 std::basic_string<my_char_t> Visualizer::Title()
  87 {
  88         return U("Music visualizer");
  89 }
  90
  91 void Visualizer::Update()
  92 {
  93         if (itsFifo < 0)
  94                 return;
  95
  96         // if mpd is stopped, clear the screen
  97         if (!Mpd.isPlaying())
  98         {
  99                 w->Clear();
 100                 return;
 101         }
 102
 103         // it supports only PCM in format 44100:16:1
 104         static int16_t buf[Samples];
 105         ssize_t data = read(itsFifo, buf, sizeof(buf));
 106         if (data < 0) // no data available in fifo
 107                 return;
 108
 109         w->Clear(0);
 110 #       ifdef HAVE_FFTW3_H
 111         Config.visualizer_use_wave ? DrawSoundWave(buf, data) : DrawFrequencySpectrum(buf, data);
 112 #       else
 113         DrawSoundWave(buf, data);
 114 #       endif // HAVE_FFTW3_H
 115         w->Refresh();
 116 }
 117
 118 void Visualizer::SpacePressed()
 119 {
 120 #       ifdef HAVE_FFTW3_H
 121         Config.visualizer_use_wave = !Config.visualizer_use_wave;
 122         ShowMessage("Visualization type: %s", Config.visualizer_use_wave ? "Sound wave" : "Frequency spectrum");
 123 #       endif // HAVE_FFTW3_H
 124 }
 125
 126 void Visualizer::DrawSoundWave(int16_t *buf, ssize_t data)
 127 {
 128         const int samples_per_col = data/sizeof(int16_t)/COLS;
 129         const int half_height = MainHeight/2;
 130         *w << fmtAltCharset;
 131         double prev_point_pos = 0;
 132         for (int i = 0; i < COLS; ++i)
 133         {
 134                 double point_pos = 0;
 135                 for (int j = 0; j < samples_per_col; ++j)
 136                         point_pos += buf[i*samples_per_col+j];
 137                 point_pos /= samples_per_col;
 138                 point_pos /= std::numeric_limits<int16_t>::max();
 139                 point_pos *= half_height;
 140                 *w << XY(i, half_height+point_pos) << '`';
 141                 if (i && abs(prev_point_pos-point_pos) > 2)
 142                 {
 143                         // if gap is too big. intermediate values are needed
 144                         // since without them all we see are blinking points
 145                         const int breakpoint = std::max(prev_point_pos, point_pos);
 146                         const int half = (prev_point_pos+point_pos)/2;
 147                         for (int k = std::min(prev_point_pos, point_pos)+1; k < breakpoint; k += 2)
 148                                         *w << XY(i-(k < half), half_height+k) << '`';
 149                 }
 150                 prev_point_pos = point_pos;
 151         }
 152         *w << fmtAltCharsetEnd;
 153 }
 154
 155 #ifdef HAVE_FFTW3_H
 156 void Visualizer::DrawFrequencySpectrum(int16_t *buf, ssize_t data)
 157 {
 158         // zero old values
 159         std::fill(buf+data/sizeof(int16_t), buf+Samples, 0);
 160         for (unsigned i = 0; i < Samples; ++i)
 161                 itsInput[i] = buf[i];
 162
 163         fftw_execute(itsPlan);
 164
 165         // count magnitude of each frequency and scale it to fit the screen
 166         for (unsigned i = 0; i < FFTResults; ++i)
 167                 itsFreqsMagnitude[i] = sqrt(itsOutput[i][0]*itsOutput[i][0] + itsOutput[i][1]*itsOutput[i][1])/1e5*LINES/5;
 168
 169         const int freqs_per_col = FFTResults/COLS /* cut bandwidth a little to achieve better look */ * 4/5;
 170         for (int i = 0; i < COLS; ++i)
 171         {
 172                 size_t bar_height = 0;
 173                 for (int j = 0; j < freqs_per_col; ++j)
 174                         bar_height += itsFreqsMagnitude[i*freqs_per_col+j];
 175                 bar_height = std::min(bar_height/freqs_per_col, MainHeight);
 176                 mvwvline(w->Raw(), MainHeight-bar_height, i, 0, bar_height);
 177         }
 178 }
 179 #endif // HAVE_FFTW3_H
 180
 181 void Visualizer::SetFD()
 182 {
 183         if (itsFifo < 0 && (itsFifo = open(Config.visualizer_fifo_path.c_str(), O_RDONLY | O_NONBLOCK)) < 0)
 184                 ShowMessage("Couldn't open \"%s\" for reading PCM data: %s", Config.visualizer_fifo_path.c_str(), strerror(errno));
 185 }
 186
 187 void Visualizer::ResetFD()
 188 {
 189         itsFifo = -1;
 190 }
 191
 192 #endif // ENABLE_VISUALIZER
 193