third_party_libsnd/examples/make_sine.c
Matthieu Poullet e6d68161d1 make_sine.c: small code cleanup.
make_sine.c: fix typo in output message.
make_sine.c: use return instead of exit in main.
make_sine.c: unify error messages.
make_sine.c: return error code if malloc fails.
make_sine.c: free memory and close file handle in error case.
2017-05-19 21:42:59 +10:00

101 lines
3.2 KiB
C

/*
** Copyright (C) 1999-2012 Erik de Castro Lopo <erikd@mega-nerd.com>
**
** All rights reserved.
**
** Redistribution and use in source and binary forms, with or without
** modification, are permitted provided that the following conditions are
** met:
**
** * Redistributions of source code must retain the above copyright
** notice, this list of conditions and the following disclaimer.
** * Redistributions in binary form must reproduce the above copyright
** notice, this list of conditions and the following disclaimer in
** the documentation and/or other materials provided with the
** distribution.
** * Neither the author nor the names of any contributors may be used
** to endorse or promote products derived from this software without
** specific prior written permission.
**
** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
** TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
** PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
** CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
** EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
** PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
** OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
** WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
** OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
** ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>
#include <sndfile.h>
#ifndef M_PI
#define M_PI 3.14159265358979323846264338
#endif
#define SAMPLE_RATE 44100
#define SAMPLE_COUNT (SAMPLE_RATE * 4) /* 4 seconds */
#define AMPLITUDE (1.0 * 0x7F000000)
#define LEFT_FREQ (344.0 / SAMPLE_RATE)
#define RIGHT_FREQ (466.0 / SAMPLE_RATE)
int
main (void)
{ SNDFILE *file ;
SF_INFO sfinfo ;
int k ;
int *buffer ;
if (! (buffer = malloc (2 * SAMPLE_COUNT * sizeof (int))))
{ printf ("Error : Malloc failed.\n") ;
return 1 ;
} ;
memset (&sfinfo, 0, sizeof (sfinfo)) ;
sfinfo.samplerate = SAMPLE_RATE ;
sfinfo.frames = SAMPLE_COUNT ;
sfinfo.channels = 2 ;
sfinfo.format = (SF_FORMAT_WAV | SF_FORMAT_PCM_24) ;
if (! (file = sf_open ("sine.wav", SFM_WRITE, &sfinfo)))
{ printf ("Error : Not able to open output file.\n") ;
free (buffer) ;
return 1 ;
} ;
if (sfinfo.channels == 1)
{ for (k = 0 ; k < SAMPLE_COUNT ; k++)
buffer [k] = AMPLITUDE * sin (LEFT_FREQ * 2 * k * M_PI) ;
}
else if (sfinfo.channels == 2)
{ for (k = 0 ; k < SAMPLE_COUNT ; k++)
{ buffer [2 * k] = AMPLITUDE * sin (LEFT_FREQ * 2 * k * M_PI) ;
buffer [2 * k + 1] = AMPLITUDE * sin (RIGHT_FREQ * 2 * k * M_PI) ;
} ;
}
else
{ printf ("Error : make_sine can only generate mono or stereo files.\n") ;
sf_close (file) ;
free (buffer) ;
return 1 ;
} ;
if (sf_write_int (file, buffer, sfinfo.channels * SAMPLE_COUNT) !=
sfinfo.channels * SAMPLE_COUNT)
puts (sf_strerror (file)) ;
sf_close (file) ;
free (buffer) ;
return 0 ;
} /* main */