static float expval_table_float[512][16];
#define FRAC_BITS 23
+#define IMDCT_SCALAR 1.759
static void mpegaudio_tableinit(void)
{
double value = i / 4;
double f, fm;
int e, m;
- f = value * cbrtf(value) * pow(2, (i & 3) * 0.25);
+ f = value / IMDCT_SCALAR * cbrtf(value) * pow(2, (i & 3) * 0.25);
fm = frexp(f, &e);
m = (uint32_t)(fm * (1LL << 31) + 0.5);
e += FRAC_BITS - 31 + 5 - 100;
}
for (exponent = 0; exponent < 512; exponent++) {
for (value = 0; value < 16; value++) {
- double f = (double)value * cbrtf(value) * pow(2, (exponent - 400) * 0.25 + FRAC_BITS + 5);
+ double f = (double)value * cbrtf(value) * pow(2, (exponent - 400) * 0.25 + FRAC_BITS + 5) / IMDCT_SCALAR;
expval_table_fixed[exponent][value] = llrint(f);
expval_table_float[exponent][value] = f;
}