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/*
Copyright (C) 2000 Stefan Westerfeld
[email protected]
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 Street, Fifth Floor, Boston, MA 02110-1301, USA.
Permission is also granted to link this program with the Qt
library, treating Qt like a library that normally accompanies the
operating system kernel, whether or not that is in fact the case.
*/
#include <iostream>
#include <math.h>
#include "audiosubsys.h"
#include "convert.h"
#include "dispatcher.h"
using namespace std;
using namespace Arts;
class SinTest : public ASProducer {
protected:
int audiofd;
int done;
AudioSubSystem *as;
bool attached;
public:
SinTest();
virtual ~SinTest();
void needMore();
void run(long samples);
};
SinTest::SinTest() : done(0), as(AudioSubSystem::the())
{
// initialize and open audio subsystem (defaults to 44kHz, 16bit, stereo)
attached = as->attachProducer(this);
if(!attached)
{
cout << "audio subsystem is already used?" << endl;
}
else
{
if(as->open() == false)
{
cout << "audio subsystem init failed ("
<< as->error() << ")" << endl;
audiofd = -1;
}
else
audiofd = as->selectWriteFD();
}
}
SinTest::~SinTest()
{
// deinitialize the audio subsystem
if(attached)
as->detachProducer();
}
void SinTest::run(long samples)
{
// run this loop until enough samples are produced
while(attached && audiofd >= 0 && (done < samples))
{
fd_set wfds, efds;
FD_ZERO(&wfds);
FD_ZERO(&efds);
FD_SET(audiofd, &wfds);
FD_SET(audiofd, &efds);
// look if the audio filedescriptor becomes writeable
int result = select(audiofd+1,0,&wfds,&efds,0);
if(result > 0)
{
// if yes, tell the audio subsystem to do something about it
if(FD_ISSET(audiofd, &wfds))
as->handleIO(AudioSubSystem::ioWrite);
if(FD_ISSET(audiofd, &efds))
as->handleIO(AudioSubSystem::ioExcept);
}
else
{
cout << "select returned " << result << endl;
}
}
}
/*
* needMore is a callback by the audio subsystem, which is made as soon as
* the internal buffers need a refill
*/
void SinTest::needMore()
{
float left[100], right[100];
unsigned char out[400];
// generate two waves, one 440 Hz (left), one 880Hz (right)
for(int i=0;i<100;i++)
{
left[i] = sin((float)i*6.28/100.0);
right[i] = sin((float)i*6.28/50.0);
}
convert_stereo_2float_i16le(100, left, right, out);
// write them to the audio subsystem
as->write(out,400);
done += 100;
}
/*
* This is intended to help testing the audio subsystem with different
* hardware without needing to use the whole server.
*
* Warning: this is *not* an example how to use aRts (there are others),
* but a simple test program for debugging purposes.
*/
int main()
{
Dispatcher d; // to get startup classes executed
// the test, generate 88100 samples (2 seconds) of pure sine wave test data
SinTest s;
s.run(88100);
return 0;
}
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