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/*
* Purpose: Test sounds for osstest
*
* Nodoc:
*/
/*
*
* 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.
*
*/
#include <string.h>
#include "wavedata.h"
extern int play_gain; // 0 to 100
static int
le_int (const unsigned char *p, int l)
{
int i, val;
val = 0;
for (i = l - 1; i >= 0; i--)
{
val = (val << 8) | p[i];
}
return val;
}
int
uncompress_wave (short *outbuf)
{
#define WAVE_FORMAT_ADPCM 0x0002
int i, n, dataleft, x, l = sizeof (inbuf);
const unsigned char *hdr = inbuf;
typedef struct
{
int coeff1, coeff2;
}
adpcm_coeff;
adpcm_coeff coeff[32];
static int AdaptionTable[] = { 230, 230, 230, 230, 307, 409, 512, 614,
768, 614, 512, 409, 307, 230, 230, 230
};
unsigned char buf[4096];
int channels = 1;
int p = 12, outp = 0;
int nBlockAlign = 2048;
int wSamplesPerBlock = 2036, wNumCoeff = 7;
int nib;
int ppp;
/* filelen = le_int (&hdr[4], 4); */
while (p < l - 16 && memcmp (&hdr[p], "data", 4) != 0)
{
n = le_int (&hdr[p + 4], 4);
if (memcmp (&hdr[p], "fmt ", 4) == 0)
{
/* fmt = le_int (&hdr[p + 8], 2); */
channels = le_int (&hdr[p + 10], 2);
/* speed = le_int (&hdr[p + 12], 4); */
nBlockAlign = le_int (&hdr[p + 20], 2);
/* bytes_per_sample = le_int (&hdr[p + 20], 2); */
wSamplesPerBlock = le_int (&hdr[p + 26], 2);
wNumCoeff = le_int (&hdr[p + 28], 2);
x = p + 30;
for (i = 0; i < wNumCoeff; i++)
{
coeff[i].coeff1 = (short) le_int (&hdr[x], 2);
x += 2;
coeff[i].coeff2 = (short) le_int (&hdr[x], 2);
x += 2;
}
}
p += n + 8;
}
if (p < l - 16 && memcmp (&hdr[p], "data", 4) == 0)
{
dataleft = n = le_int (&hdr[p + 4], 4);
p += 8;
/*
* Playback procedure
*/
#define OUT_SAMPLE(s) { \
if (s>32767)s=32767;else if(s<-32768)s=-32768; \
outbuf[outp++] = (s*play_gain) / 100; \
n+=2; \
}
#define GETNIBBLE \
((nib==0) ? \
(buf[x + nib++] >> 4) & 0x0f : \
buf[x++ + --nib] & 0x0f \
)
outp = 0;
ppp = p;
while (dataleft > nBlockAlign)
{
int predictor[2], delta[2], samp1[2], samp2[2];
int x = 0;
memcpy (buf, &inbuf[ppp], nBlockAlign);
ppp += nBlockAlign;
dataleft -= nBlockAlign;
nib = 0;
n = 0;
for (i = 0; i < channels; i++)
{
predictor[i] = buf[x];
x++;
}
for (i = 0; i < channels; i++)
{
delta[i] = (short) le_int (&buf[x], 2);
x += 2;
}
for (i = 0; i < channels; i++)
{
samp1[i] = (short) le_int (&buf[x], 2);
x += 2;
OUT_SAMPLE (samp1[i]);
}
for (i = 0; i < channels; i++)
{
samp2[i] = (short) le_int (&buf[x], 2);
x += 2;
OUT_SAMPLE (samp2[i]);
}
while (n < (wSamplesPerBlock * 2 * channels))
for (i = 0; i < channels; i++)
{
int pred, new, error_delta, i_delta;
pred = ((samp1[i] * coeff[predictor[i]].coeff1)
+ (samp2[i] * coeff[predictor[i]].coeff2)) / 256;
i_delta = error_delta = GETNIBBLE;
if (i_delta & 0x08)
i_delta -= 0x10; /* Convert to signed */
new = pred + (delta[i] * i_delta);
OUT_SAMPLE (new);
delta[i] = delta[i] * AdaptionTable[error_delta] / 256;
if (delta[i] < 16)
delta[i] = 16;
samp2[i] = samp1[i];
samp1[i] = new;
}
}
}
return outp * 2;
}
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