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/*
Audio File Library
Copyright (c) 1998-1999, Michael Pruett <michael@68k.org>
Copyright (c) 2001, Silicon Graphics, Inc.
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., 59 Temple Place, Suite 330, Boston,
MA 02111-1307, USA.
*/
/*
linuxtest.c
This file plays a 16-bit, 44.1 kHz monophonic or stereophonic
audio file through a PC sound card on a Linux system. This file
will not compile under any operating system that does not support
the Open Sound System API.
*/
#include <stdio.h>
#include <sys/ioctl.h>
#include <unistd.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <linux/soundcard.h>
#include <audiofile.h>
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
/*
If it's not defined already, define the native audio hardware
byte order.
*/
#ifndef AFMT_S16_NE
#ifdef WORDS_BIGENDIAN /* defined in config.h */
#define AFMT_S16_NE AFMT_S16_BE
#else
#define AFMT_S16_NE AFMT_S16_LE
#endif /* WORDS_BIGENDIAN */
#endif /* AFMT_S16_NE */
void setupdsp (int audiofd, int channelCount);
void usage (void);
/* BUFFER_FRAMES represents the size of the buffer in frames. */
#define BUFFER_FRAMES 4096
int main (int argc, char **argv)
{
AFfilehandle file;
AFframecount frameCount, framesRead;
int sampleFormat, sampleWidth, channelCount;
float frameSize;
void *buffer;
int audiofd;
if (argc != 2)
usage();
file = afOpenFile(argv[1], "r", NULL);
frameCount = afGetFrameCount(file, AF_DEFAULT_TRACK);
printf("frame count: %d\n", (int) frameCount);
channelCount = afGetVirtualChannels(file, AF_DEFAULT_TRACK);
afGetVirtualSampleFormat(file, AF_DEFAULT_TRACK, &sampleFormat,
&sampleWidth);
frameSize = afGetVirtualFrameSize(file, AF_DEFAULT_TRACK, 1);
printf("sample format: %d, sample width: %d, channels: %d\n",
sampleFormat, sampleWidth, channelCount);
if ((sampleFormat != AF_SAMPFMT_TWOSCOMP) &&
(sampleFormat != AF_SAMPFMT_UNSIGNED))
{
fprintf(stderr, "The audio file must contain integer data in two's complement or unsigned format.\n");
exit(EXIT_FAILURE);
}
if ((sampleWidth != 16) || (channelCount > 2))
{
fprintf(stderr, "The audio file must be of a 16-bit monophonic or stereophonic format.\n");
exit(EXIT_FAILURE);
}
buffer = malloc(BUFFER_FRAMES * frameSize);
audiofd = open("/dev/dsp", O_WRONLY);
if (audiofd < 0)
{
perror("open");
exit(EXIT_FAILURE);
}
setupdsp(audiofd, channelCount);
framesRead = afReadFrames(file, AF_DEFAULT_TRACK, buffer,
BUFFER_FRAMES);
while (framesRead > 0)
{
printf("read %ld frames\n", framesRead);
write(audiofd, buffer, framesRead * frameSize);
framesRead = afReadFrames(file, AF_DEFAULT_TRACK, buffer,
BUFFER_FRAMES);
}
close(audiofd);
free(buffer);
return 0;
}
void setupdsp (int audiofd, int channelCount)
{
int format, frequency, channels;
format = AFMT_S16_NE;
if (ioctl(audiofd, SNDCTL_DSP_SETFMT, &format) == -1)
{
perror("set format");
exit(EXIT_FAILURE);
}
if (format != AFMT_S16_NE)
{
fprintf(stderr, "format not correct.\n");
exit(EXIT_FAILURE);
}
channels = channelCount;
if (ioctl(audiofd, SNDCTL_DSP_CHANNELS, &channels) == -1)
{
perror("set channels");
exit(EXIT_FAILURE);
}
frequency = 44100;
if (ioctl(audiofd, SNDCTL_DSP_SPEED, &frequency) == -1)
{
perror("set frequency");
exit(EXIT_FAILURE);
}
}
void usage (void)
{
fprintf(stderr, "usage: linuxtest file\n");
fprintf(stderr,
"where file refers to a 16-bit monophonic or stereophonic 44.1 kHz audio file\n");
exit(EXIT_FAILURE);
}
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