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version 1.4.1

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This commit is contained in:
Jared Szechy
2011-08-21 03:36:53 -04:00
parent 59f8d3890e
commit b1024fba95
24 changed files with 818 additions and 395 deletions
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163
dsd_upsample.c
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@@ -22,150 +22,47 @@ upsample (dsd_state * state, float invalue)
{
int i, j, sum;
float *outbuf1, a, b, c, d;
float phasestart, phaseend, resamplestart, resampleend, phasestep, resampleamp2;
float resamplemin, resamplemax;
float *outbuf1, c, d;
if (state->audio_out_idx2 > 23)
outbuf1 = state->audio_out_float_buf_p;
outbuf1--;
c = *outbuf1;
d = invalue;
// basic triangle interpolation
outbuf1++;
*outbuf1 = ((invalue * (float) 0.166) + (c * (float) 0.834));
outbuf1++;
*outbuf1 = ((invalue * (float) 0.332) + (c * (float) 0.668));
outbuf1++;
*outbuf1 = ((invalue * (float) 0.5) + (c * (float) 0.5));
outbuf1++;
*outbuf1 = ((invalue * (float) 0.668) + (c * (float) 0.332));
outbuf1++;
*outbuf1 = ((invalue * (float) 0.834) + (c * (float) 0.166));
outbuf1++;
*outbuf1 = d;
outbuf1++;
if (state->audio_out_idx2 > 24)
{
outbuf1 = state->audio_out_float_buf_p;
outbuf1--;
c = *outbuf1;
outbuf1 -= 6;
b = *outbuf1;
outbuf1 -= 6;
a = *outbuf1;
d = (invalue);
resamplemin = 32767;
resamplemax = -32768;
if (a < resamplemin)
// smoothing
outbuf1 -= 16;
for (j = 0; j < 4; j++)
{
resamplemin = a;
}
if (a > resamplemax)
{
resamplemax = a;
}
if (b < resamplemin)
{
resamplemin = b;
}
if (b > resamplemax)
{
resamplemax = b;
}
if (c < resamplemin)
{
resamplemin = c;
}
if (c > resamplemax)
{
resamplemax = c;
}
if (d < resamplemin)
{
resamplemin = d;
}
if (d > resamplemax)
{
resamplemax = d;
}
resampleamp2 = ((float) resamplemax - (float) resamplemin) / (float) 2;
#ifdef UPSAMPLE_DEBUG
printf ("a:%f b:%f c:%f d:%f resamplemin:%f resamplemax:%f resampleamp2:%f\n", a, b, c, d, resamplemin, resamplemax, resampleamp2);
#endif
if (resampleamp2 == 0)
{
resamplestart = (float) 0;
resampleend = (float) 0;
}
else
{
resamplestart = (((float) b - (float) resamplemin) / resampleamp2) - (float) 1.0;
resampleend = (((float) c - (float) resamplemin) / resampleamp2) - (float) 1.0;
}
if (resamplestart < -1)
{
resamplestart = (float) -1;
}
else if (resamplestart > (float) 1)
{
resamplestart = (float) 1;
}
if (resampleend < -1)
{
resampleend = (float) -1;
}
else if (resampleend > (float) 1)
{
resampleend = (float) 1;
}
phasestart = asinf (resamplestart);
phaseend = asinf (resampleend);
phasestep = (phaseend - phasestart) / 6;
#ifdef UPSAMPLE_DEBUG
printf ("resamplestart:%f, resampleend:%f, phasestart:%f, phaseend:%f, phasestep:%f\n", resamplestart, resampleend, phasestart, phaseend, phasestep);
#endif
// rewrite samples between b and c
outbuf1 = state->audio_out_float_buf_p;
outbuf1 -= 6;
for (i = 1; i < 6; i++)
{
*outbuf1 = (resamplemin + resampleamp2 + (resampleamp2 * sin (phasestart + (phasestep * (float) i))));
#ifdef UPSAMPLE_DEBUG
printf ("audio_out_idx2:%i outbuf:%f\n", state->audio_out_idx2, *outbuf1);
#endif
outbuf1++;
}
#ifdef UPSAMPLE_DEBUG
printf ("(c):%f\n", *outbuf1);
#endif
// write d
outbuf1 += 6;
*outbuf1 = d;
#ifdef UPSAMPLE_DEBUG
printf ("audio_out_idx2:%i outbuf(d):%f\n", state->audio_out_idx2, *outbuf1);
#endif
outbuf1++;
// smooth
outbuf1 -= 36;
for (j = 0; j < 12; j++)
{
for (i = 0; i < 12; i++)
for (i = 0; i < 6; i++)
{
sum = 0;
outbuf1--;
outbuf1 -= 2;
sum += *outbuf1;
outbuf1++;
outbuf1 += 2;
sum += *outbuf1;
outbuf1++;
outbuf1 += 2;
sum += *outbuf1;
outbuf1--;
outbuf1 -= 2;
*outbuf1 = (sum / (float) 3);
outbuf1++;
}
outbuf1 -= 11;
outbuf1 -= 8;
}
}
else
{
outbuf1 = state->audio_out_float_buf_p;
outbuf1--;
c = *outbuf1;
*outbuf1 = ((invalue * (float) 0.166) + (c * (float) 0.834));
outbuf1++;
*outbuf1 = ((invalue * (float) 0.332) + (c * (float) 0.668));
outbuf1++;
*outbuf1 = ((invalue * (float) 0.5) + (c * (float) 0.5));
outbuf1++;
*outbuf1 = ((invalue * (float) 0.668) + (c * (float) 0.332));
outbuf1++;
*outbuf1 = ((invalue * (float) 0.834) + (c * (float) 0.166));
outbuf1++;
*outbuf1 = invalue;
}
}