ref: 00fb6b07653b60095ead739993c9d40773e4d14d
parent: ab220aa212ed9c37a7dd6850660db346b07821dd
author: Jean-Marc Valin <jean-marc.valin@usherbrooke.ca>
date: Tue Sep 15 19:39:27 EDT 2009
fixed-point: denorm pitch converted
--- a/libcelt/bands.c
+++ b/libcelt/bands.c
@@ -219,31 +219,50 @@
int compute_new_pitch(const CELTMode *m, const celt_sig_t *X, const celt_sig_t *P, int *gain_id)
{int j ;
- float g;
+ celt_word16_t g;
const int C = CHANNELS(m);
- float Sxy=0, Sxx=0, Syy=0;
+ celt_word32_t Sxy=0, Sxx=0, Syy=0;
int len = 20*C;
-
+#ifdef FIXED_POINT
+ int shift = 0;
+ celt_word32_t maxabs=0;
for (j=0;j<len;j++)
{- float gg = 1-1.*j/len;
-#ifdef FIXED_POINT
- Sxy += X[j] * gg*P[j];
- Sxx += gg*P[j]* gg*P[j];
- Syy += X[j] *1.*X[j];
-#else
- Sxy = MAC16_16(Sxy, X[j], gg*P[j]);
- Sxx = MAC16_16(Sxx, gg*P[j], gg*P[j]);
- Syy = MAC16_16(Syy, X[j], X[j]);
+ maxabs = MAX32(maxabs, ABS32(X[j]));
+ maxabs = MAX32(maxabs, ABS32(P[j]));
+ }
+ shift = celt_ilog2(maxabs)-12;
+ if (shift<0)
+ shift = 0;
#endif
+ for (j=0;j<len;j++)
+ {+ celt_word16_t gg = Q15ONE-DIV32_16(MULT16_16(Q15ONE,j),len);
+ celt_word16_t Xj, Pj;
+ Xj = EXTRACT16(SHR32(X[j], shift));
+ Pj = MULT16_16_P15(gg,EXTRACT16(SHR32(P[j], shift)));
+ Sxy = MAC16_16(Sxy, Xj, Pj);
+ Sxx = MAC16_16(Sxx, Pj, Pj);
+ Syy = MAC16_16(Syy, Xj, Xj);
}
- g = QCONST16(1.,14)*Sxy/(.1+Sxx+.03*Syy);
- if (Sxy/sqrt(.1+Sxx*Syy) < .5)
- g = 0;
#ifdef FIXED_POINT
- /* This MUST round down */
- *gain_id = EXTRACT16(SHR32(MULT16_16(20,(g-QCONST16(.5,14))),14));
+ {+ celt_word32_t num, den;
+ num = Sxy;
+ den = EPSILON+Sxx+MULT16_32_Q15(QCONST16(.03,15),Syy);
+ shift = celt_ilog2(Sxy)-16;
+ if (shift < 0)
+ shift = 0;
+ g = DIV32(SHL32(SHR32(num,shift),14),SHR32(den,shift));
+ if (Sxy < SHR32(MULT16_16(celt_sqrt(EPSILON+Sxx),celt_sqrt(EPSILON+Syy)),1))
+ g = 0;
+ /* This MUST round down */
+ *gain_id = EXTRACT16(SHR32(MULT16_16(20,(g-QCONST16(.5,14))),14));
+ }
#else
+ g = Sxy/(.1+Sxx+.03*Syy);
+ if (Sxy < .5*celt_sqrt(.1+Sxx*Syy))
+ g = 0;
*gain_id = floor(20*(g-.5));
#endif
if (*gain_id < 0)
--
⑨