ref: c7b01bad5018ba110320fd1b674a1d05410c1483
parent: dc8a6eee433ef2cf8866d7bfe051c331d6607a81
author: Jean-Marc Valin <[email protected]>
date: Fri Mar 19 19:17:28 EDT 2010
fixed-point: slightly increasing the decoder accuracy again
--- a/libcelt/quant_bands.c
+++ b/libcelt/quant_bands.c
@@ -110,7 +110,7 @@
celt_word16 q;
celt_word16 x;
celt_word16 f;
- celt_word16 mean = (i-start < E_MEANS_SIZE) ? MULT16_16_P15(Q15ONE-coef,eMeans[i-start]) : 0;
+ celt_word16 mean = (i-start < E_MEANS_SIZE) ? SUB16(eMeans[i-start], MULT16_16_P15(coef,eMeans[i-start])) : 0;
x = eBands[i+c*m->nbEBands];
#ifdef FIXED_POINT
f = x-mean -MULT16_16_P15(coef,oldEBands[i+c*m->nbEBands])-prev[c];
@@ -135,7 +135,7 @@
q = SHL16(qi,DB_SHIFT);
oldEBands[i+c*m->nbEBands] = MULT16_16_P15(coef,oldEBands[i+c*m->nbEBands])+(mean+prev[c]+q);
- prev[c] = mean+prev[c]+MULT16_16_P15(Q15ONE-beta,q);
+ prev[c] = mean+prev[c]+q-MULT16_16_P15(beta,q);
} while (++c < C);
}
return bits_used;
@@ -235,11 +235,11 @@
/* Decode at a fixed coarse resolution */
for (i=start;i<m->nbEBands;i++)
{- c=0;
+ c=0;
do {int qi;
celt_word16 q;
- celt_word16 mean = (i-start < E_MEANS_SIZE) ? MULT16_16_P15(Q15ONE-coef,eMeans[i-start]) : 0;
+ celt_word16 mean = (i-start < E_MEANS_SIZE) ? SUB16(eMeans[i-start], MULT16_16_P15(coef,eMeans[i-start])) : 0;
/* If we didn't have enough bits to encode all the energy, just assume something safe.
We allow slightly busting the budget here */
if (ec_dec_tell(dec, 0) > budget)
@@ -249,7 +249,7 @@
q = SHL16(qi,DB_SHIFT);
oldEBands[i+c*m->nbEBands] = MULT16_16_P15(coef,oldEBands[i+c*m->nbEBands])+(mean+prev[c]+q);
- prev[c] = mean+prev[c]+MULT16_16_P15(Q15ONE-beta,q);
+ prev[c] = mean+prev[c]+q-MULT16_16_P15(beta,q);
} while (++c < C);
}
}
--- a/libcelt/vq.c
+++ b/libcelt/vq.c
@@ -75,8 +75,8 @@
celt_norm x1, x2;
x1 = Xptr[0];
x2 = Xptr[stride];
- Xptr[stride] = MULT16_16_Q15(c,x2) + MULT16_16_Q15(s,x1);
- *Xptr++ = MULT16_16_Q15(c,x1) - MULT16_16_Q15(s,x2);
+ Xptr[stride] = EXTRACT16(SHR32(MULT16_16(c,x2) + MULT16_16(s,x1),15));
+ *Xptr++ = EXTRACT16(SHR32(MULT16_16(c,x1) - MULT16_16(s,x2),15));
}
Xptr = &X[len-2*stride-1];
for (i=len-2*stride-1;i>=0;i--)
@@ -84,8 +84,8 @@
celt_norm x1, x2;
x1 = Xptr[0];
x2 = Xptr[stride];
- Xptr[stride] = MULT16_16_Q15(c,x2) + MULT16_16_Q15(s,x1);
- *Xptr-- = MULT16_16_Q15(c,x1) - MULT16_16_Q15(s,x2);
+ Xptr[stride] = EXTRACT16(SHR32(MULT16_16(c,x2) + MULT16_16(s,x1),15));
+ *Xptr-- = EXTRACT16(SHR32(MULT16_16(c,x1) - MULT16_16(s,x2),15));
}
}
/*if (len==30)