Rivendellaudio/lib/rdwavescene.cpp
Fred Gleason 0892892407 2021-04-12 Fred Gleason <fredg@paravelsystems.com>
* Added a 'DISTRO-SPECIFIC NOTES' section to 'INSTALL'.

Signed-off-by: Fred Gleason <fredg@paravelsystems.com>
2021-04-12 16:12:52 -04:00

68 lines
1.8 KiB
C++

// rdwavescene.cpp
//
// GraphicsScene Class for Drawing Audio Waveforms
//
// (C) Copyright 2021 Fred Gleason <fredg@paravelsystems.com>
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License version 2 as
// published by the Free Software Foundation.
//
// 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 <math.h>
#include "rdwavescene.h"
RDWaveScene::RDWaveScene(const QList<uint16_t> &energy,int x_shrink,qreal gain,
int height,QObject *parent)
: QGraphicsScene(0,0,energy.size()/x_shrink,height,parent)
{
d_energy_data=energy;
d_x_shrink_factor=x_shrink;
d_audio_gain=gain;
d_height=(qreal)height;
//
// Gain Ratio
//
qreal ratio=exp10(d_audio_gain/20.0);
//
// Waveform
//
for(int i=0;i<energy.size();i+=x_shrink) {
// printf("energy[%d]: %u\n",i,0xFFFF&energy.at(i));
uint16_t lvl=energy.at(i);
for(int j=1;j<x_shrink;j++) {
if(((i+j)<energy.size())&&(energy.at(i+j))>lvl) {
lvl=energy.at(i+j);
}
}
// qreal rlvl=ratio*(qreal)lvl/327.67;
qreal rlvl=ratio*(qreal)lvl*d_height/65534.0;
// Bottom half
addRect((qreal)(i/x_shrink),d_height/2.0,
(qreal)1,rlvl,
QPen(Qt::black),QBrush(Qt::black));
// Top half
addRect((qreal)(i/x_shrink),d_height/2.0,
(qreal)1,-rlvl,
QPen(Qt::black),QBrush(Qt::black));
}
}
RDWaveScene::~RDWaveScene()
{
}