ref: 6a2432280dba6df6d13afe5850b1499062c43be5
dir: /src/skeleff.c/
/*
* skeleff - Skelton Effect. Use as sample for new effects.
*
* Written by Chris Bagwell (cbagwell@sprynet.com) - March 16, 1999
*
* Copyright 1999 Chris Bagwell And Sundry Contributors
* This source code is freely redistributable and may be used for
* any purpose. This copyright notice must be maintained.
* Chris Bagwell And Sundry Contributors are not responsible for
* the consequences of using this software.
*/
#include "st_i.h"
/* Private data for SKEL file */
typedef struct skelleffstuff {
int localdata;
} *skeleff_t;
/*
* Process options
*
* Don't do initialization now.
* The 'info' fields are not yet filled in.
*/
int st_skeleff_getopts(eff_t effp, int n, char **argv)
{
skeleff_t skeleff = (skeleff_t) effp->priv;
if (n)
{
if (n != 1)
{
st_fail("Usage: skeleff [option]");
return (ST_EOF);
}
}
return (ST_SUCCESS);
}
/*
* Prepare processing.
* Do all initializations.
*/
int st_skeleff_start(eff_t effp)
{
if (effp->outinfo.channels == 1)
{
st_fail("Can't run skeleff on mono data.");
return (ST_EOF);
}
return (ST_SUCCESS);
}
/*
* Processed signed long samples from ibuf to obuf.
* Return number of samples processed.
*/
int st_skeleff_flow(eff_t effp, st_sample_t *ibuf, st_sample_t *obuf,
st_size_t *isamp, st_size_t *osamp)
{
skeleff_t skeleff = (skeleff_t) effp->priv;
int len, done;
switch (effp->outinfo.channels)
{
case 2:
/* Length to process will be buffer length / 2 since we
* work with two samples at a time.
*/
len = ((*isamp > *osamp) ? *osamp : *isamp) / 2;
for(done = 0; done < len; done++)
{
obuf[0] = ibuf[0];
obuf[1] = ibuf[1];
/* Advance buffer by 2 samples */
ibuf += 2;
obuf += 2;
}
*isamp = len * 2;
*osamp = len * 2;
break;
}
return (ST_SUCCESS);
}
/*
* Drain out remaining samples if the effect generates any.
*/
int st_skeleff_drain(eff_t effp, st_sample_t *obuf, st_size_t *osamp)
{
*osamp = 0;
/* Help out application and return ST_EOF when drain
* will not return any mre information. *osamp == 0
* also indicates that.
*/
return (ST_EOF);
}
/*
* Do anything required when you stop reading samples.
* (free allocated memory, etc.)
*/
int st_skeleff_stop(eff_t effp)
{
/* nothing to do */
return (ST_SUCCESS);
}