ref: 5da938b2dbe4fa4bd9bf3b81f306f8bb595466b5
parent: 986e2695373f94d9572dbe08bb7cb87f01d9217b
author: Jean-Marc Valin <[email protected]>
date: Thu Jan 20 19:07:03 EST 2011
Reorders some operations in anti-collapse to reuse values
--- a/libcelt/bands.c
+++ b/libcelt/bands.c
@@ -217,42 +217,51 @@
celt_word16 *prev2logE, int *pulses, celt_uint32 seed)
{int c, i, j, k;
- c=0; do
+ for (i=start;i<end;i++)
{- for (i=start;i<end;i++)
+ int N0;
+ celt_word16 thresh, sqrt_1;
+ int depth;
+#ifdef FIXED_POINT
+ int shift;
+#endif
+
+ N0 = m->eBands[i+1]-m->eBands[i];
+ depth = (1+(pulses[i]>>BITRES))/(m->eBands[i+1]-m->eBands[i]<<LM);
+
+#ifdef FIXED_POINT
+ thresh = MULT16_32_Q15(QCONST16(0.3f, 15), MIN32(32767,SHR32(celt_exp2(-SHL16(depth, 11)),1) ));
{+ celt_word32 t;
+ t = N0<<LM;
+ shift = celt_ilog2(t)>>1;
+ t = SHL32(t, (7-shift)<<1);
+ sqrt_1 = celt_rsqrt_norm(t);
+ }
+#else
+ thresh = .3f*celt_exp2(-depth);
+ sqrt_1 = celt_rsqrt(N0<<LM);
+#endif
+
+ c=0; do
+ {celt_norm *X;
- int N0;
celt_word16 Ediff;
celt_word16 r;
- celt_word16 thresh;
- int depth;
-
- N0 = m->eBands[i+1]-m->eBands[i];
Ediff = logE[c*m->nbEBands+i]-MIN16(prev1logE[c*m->nbEBands+i],prev2logE[c*m->nbEBands+i]);
Ediff = MAX16(0, Ediff);
- depth = (1+(pulses[i]>>BITRES))/(m->eBands[i+1]-m->eBands[i]<<LM);
#ifdef FIXED_POINT
- thresh = MULT16_32_Q15(QCONST16(0.3f, 15), MIN32(32767,SHR32(celt_exp2(-SHL16(depth, 11)),1) ));
if (Ediff < 16384)
r = 2*MIN16(16383,SHR32(celt_exp2(-SHL16(Ediff, 11-DB_SHIFT)),1));
else
r = 0;
r = SHR16(MIN16(thresh, r),1);
- {- int shift;
- celt_word32 t;
- t = N0<<LM;
- shift = celt_ilog2(t)>>1;
- t = SHL32(t, (7-shift)<<1);
- r = SHR32(MULT16_16_Q15(celt_rsqrt_norm(t), r),shift);
- }
+ r = SHR32(MULT16_16_Q15(sqrt_1, r),shift);
#else
- thresh = .3f*celt_exp2(-depth);
r = 2.f*celt_exp2(-Ediff);
r = MIN16(thresh, r);
- r = r*celt_rsqrt(N0<<LM);
+ r = r*sqrt_1;
#endif
X = _X+c*size+(m->eBands[i]<<LM);
for (k=0;k<1<<LM;k++)
@@ -270,8 +279,8 @@
}
/* We just added some energy, so we need to renormalise */
renormalise_vector(X, N0<<LM, Q15ONE);
- }
- } while (++c<C);
+ } while (++c<C);
+ }
}