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/*
* Purpose: Local output buffer to device export routine for vmix (int)
*/
/*
*
* This file is part of Open Sound System.
*
* Copyright (C) 4Front Technologies 1996-2008.
*
* This this source file is released under GPL v2 license (no other versions).
* See the COPYING file included in the main directory of this source
* distribution for the license terms and conditions.
*
*/
int i, ch, och;
int vol;
#define RANGE_MAX ((1<<24)-1)
#define RANGE_MIN -(1<<24)
vol = vmix_db_table[eng->outvol / 5];
for (ch = 0; ch < channels; ch++)
{
int vu;
int *chbuf;
och = eng->channel_order[ch];
op = (SAMPLE_TYPE *) outbuf;
op += och;
chbuf = chbufs[ch];
vu = eng->vu[och % 2];
vu = vu * 65536;
for (i = 0; i < samples; i++)
{
int tmp;
tmp = *chbuf++;
tmp = (tmp * vol) / VMIX_VOL_SCALE;
/*
* Check for clipping. Decrease volume if necessary.
*/
if (tmp<RANGE_MIN)
{
tmp=RANGE_MIN;
eng->outvol -= 1;
vol /= 2;
}
else
if (tmp>RANGE_MAX)
{
tmp=RANGE_MAX;
eng->outvol -= 1;
vol /= 2;
}
*op = VMIX_BYTESWAP(INT_EXPORT(tmp));
op += channels;
/* VU meter */
if (tmp < 0)
tmp = -tmp;
if (tmp > vu)
vu = tmp;
}
if (och < 2)
{
vu = vu / 65536;
eng->vu[och] = vu;
}
}
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