ref: 5752d659fda9194a95542093498e669d7059d725
parent: 91f8010108a88e7578a177dde0f800bef2e0f00b
author: Jean-Marc Valin <[email protected]>
date: Tue Dec 10 19:21:38 EST 2013
Minor fixed-point accuracy improvements that were completely free
--- a/celt/bands.c
+++ b/celt/bands.c
@@ -367,7 +367,7 @@
celt_norm r, l;
l = X[j];
r = Y[j];
- X[j] = MULT16_16_Q14(a1,l) + MULT16_16_Q14(a2,r);
+ X[j] = EXTRACT16(SHR32(MAC16_16(MULT16_16(a1, l), a2, r), 14));
/* Side is not encoded, no need to calculate */
}
}
@@ -377,11 +377,11 @@
int j;
for (j=0;j<N;j++)
{- celt_norm r, l;
- l = MULT16_16_Q15(QCONST16(.70710678f,15), X[j]);
- r = MULT16_16_Q15(QCONST16(.70710678f,15), Y[j]);
- X[j] = l+r;
- Y[j] = r-l;
+ opus_val32 r, l;
+ l = MULT16_16(QCONST16(.70710678f, 15), X[j]);
+ r = MULT16_16(QCONST16(.70710678f, 15), Y[j]);
+ X[j] = EXTRACT16(SHR32(ADD32(l, r), 15));
+ Y[j] = EXTRACT16(SHR32(SUB32(r, l), 15));
}
}
@@ -597,11 +597,11 @@
for (i=0;i<stride;i++)
for (j=0;j<N0;j++)
{- celt_norm tmp1, tmp2;
- tmp1 = MULT16_16_Q15(QCONST16(.70710678f,15), X[stride*2*j+i]);
- tmp2 = MULT16_16_Q15(QCONST16(.70710678f,15), X[stride*(2*j+1)+i]);
- X[stride*2*j+i] = tmp1 + tmp2;
- X[stride*(2*j+1)+i] = tmp1 - tmp2;
+ opus_val32 tmp1, tmp2;
+ tmp1 = MULT16_16(QCONST16(.70710678f,15), X[stride*2*j+i]);
+ tmp2 = MULT16_16(QCONST16(.70710678f,15), X[stride*(2*j+1)+i]);
+ X[stride*2*j+i] = EXTRACT16(SHR32(ADD32(tmp1, tmp2), 15));
+ X[stride*(2*j+1)+i] = EXTRACT16(SHR32(SUB32(tmp1, tmp2), 15));
}
}