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/*
* madplay - MPEG audio decoder and player
* Copyright (C) 2000-2004 Robert Leslie
*
* 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
*
* $Id: audio_null.c,v 1.17 2004/01/23 09:41:31 rob Exp $
*/
# ifdef HAVE_CONFIG_H
# include "config.h"
# endif
# include "global.h"
# include <mad.h>
# include "audio.h"
static
int init(struct audio_init *init)
{
return 0;
}
static
int config(struct audio_config *config)
{
return 0;
}
static
void update_stats(struct audio_stats *stats,
unsigned int nsamples, mad_fixed_t const *sample)
{
enum {
MIN = -MAD_F_ONE,
MAX = MAD_F_ONE - 1
};
while (nsamples--) {
if (*sample >= stats->peak_sample) {
stats->peak_sample = *sample;
if (*sample > MAX && *sample - MAX > stats->peak_clipping)
stats->peak_clipping = *sample - MAX;
}
else if (*sample < -stats->peak_sample) {
stats->peak_sample = -*sample;
if (*sample < MIN && MIN - *sample > stats->peak_clipping)
stats->peak_clipping = MIN - *sample;
}
++sample;
}
}
static
int play(struct audio_play *play)
{
update_stats(play->stats, play->nsamples, play->samples[0]);
if (play->samples[1])
update_stats(play->stats, play->nsamples, play->samples[1]);
return 0;
}
static
int stop(struct audio_stop *stop)
{
return 0;
}
static
int finish(struct audio_finish *finish)
{
return 0;
}
int audio_null(union audio_control *control)
{
audio_error = 0;
switch (control->command) {
case AUDIO_COMMAND_INIT:
return init(&control->init);
case AUDIO_COMMAND_CONFIG:
return config(&control->config);
case AUDIO_COMMAND_PLAY:
return play(&control->play);
case AUDIO_COMMAND_STOP:
return stop(&control->stop);
case AUDIO_COMMAND_FINISH:
return finish(&control->finish);
}
return 0;
}
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