sm64ex-coop/tools/sdk-tools/adpcm/vdecode.c

74 lines
1.4 KiB
C

#include <stdio.h>
#include "vadpcm.h"
void vdecodeframe(FILE *ifile, s32 *outp, s32 order, s32 ***coefTable)
{
s32 optimalp;
s32 scale;
s32 maxlevel;
s32 i;
s32 j;
s32 in_vec[16];
s32 ix[16];
u8 header;
u8 c;
maxlevel = 7;
fread(&header, 1, 1, ifile);
scale = 1 << (header >> 4);
optimalp = header & 0xf;
for (i = 0; i < 16; i += 2)
{
fread(&c, 1, 1, ifile);
ix[i] = c >> 4;
ix[i + 1] = c & 0xf;
if (ix[i] <= maxlevel)
{
ix[i] *= scale;
}
else
{
ix[i] = (-0x10 - -ix[i]) * scale;
}
if (ix[i + 1] <= maxlevel)
{
ix[i + 1] *= scale;
}
else
{
ix[i + 1] = (-0x10 - -ix[i + 1]) * scale;
}
}
for (j = 0; j < 2; j++)
{
for (i = 0; i < 8; i++)
{
in_vec[i + order] = ix[j * 8 + i];
}
if (j == 0)
{
for (i = 0; i < order; i++)
{
in_vec[i] = outp[16 - order + i];
}
}
else
{
for (i = 0; i < order; i++)
{
in_vec[i] = outp[j * 8 - order + i];
}
}
for (i = 0; i < 8; i++)
{
outp[i + j * 8] = inner_product(order + 8, coefTable[optimalp][i], in_vec);
}
}
}