ref: bd0610d21b28b76095a49e601df44fb792b96369
parent: 5503f11a3d77b68c6f5b7b229fdd7d8ce2bff005
author: Jean-Marc Valin <[email protected]>
date: Sat Mar 13 05:04:19 EST 2010
Increasing log energy resolution
--- a/libcelt/arch.h
+++ b/libcelt/arch.h
@@ -96,7 +96,7 @@
#define PGAIN_SCALING_1 (1.f/32768.f)
#define PGAIN_SHIFT 15
-#define DB_SHIFT 8
+#define DB_SHIFT 10
#define EPSILON 1
#define VERY_SMALL 0
--- a/libcelt/mathops.h
+++ b/libcelt/mathops.h
@@ -315,7 +315,7 @@
i = celt_ilog2(x);
n = VSHR32(x,i-15)-32768-16384;
frac = ADD16(C[0], MULT16_16_Q15(n, ADD16(C[1], MULT16_16_Q15(n, ADD16(C[2], MULT16_16_Q15(n, (C[3])))))));
- return SHL16(i-13,8)+SHR16(frac,14-8);
+ return SHL16(i-13,DB_SHIFT)+SHR16(frac,14-DB_SHIFT);
}
/*
--- a/libcelt/quant_bands.c
+++ b/libcelt/quant_bands.c
@@ -44,11 +44,7 @@
#define E_MEANS_SIZE (5)
-#ifdef FIXED_POINT
-const celt_word16 eMeans[E_MEANS_SIZE] = {1920, -341, -512, -107, 43};-#else
-const celt_word16 eMeans[E_MEANS_SIZE] = {7.5f, -1.33f, -2.f, -0.42f, 0.17f};-#endif
+const celt_word16 eMeans[E_MEANS_SIZE] = {QCONST16(7.5f,DB_SHIFT), -QCONST16(1.33f,DB_SHIFT), -QCONST16(2.f,DB_SHIFT), -QCONST16(0.42f,DB_SHIFT), QCONST16(0.17f,DB_SHIFT)};/* FIXME: Implement for stereo */
int intra_decision(celt_word16 *eBands, celt_word16 *oldEBands, int len)
@@ -60,7 +56,7 @@
celt_word16 d = SUB16(eBands[i], oldEBands[i]);
dist = MAC16_16(dist, d,d);
}
- return SHR32(dist,16) > 2*len;
+ return SHR32(dist,2*DB_SHIFT) > 2*len;
}
int *quant_prob_alloc(const CELTMode *m)
@@ -111,15 +107,15 @@
c=0;
do {int qi;
- celt_word16 q; /* dB */
- celt_word16 x; /* dB */
- celt_word16 f; /* Q8 */
+ 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;
x = eBands[i+c*m->nbEBands];
#ifdef FIXED_POINT
f = x-mean -MULT16_16_P15(coef,oldEBands[i+c*m->nbEBands])-prev[c];
/* Rounding to nearest integer here is really important! */
- qi = (f+128)>>8;
+ qi = (f+QCONST16(.5,DB_SHIFT))>>DB_SHIFT;
#else
f = x-mean-coef*oldEBands[i+c*m->nbEBands]-prev[c];
/* Rounding to nearest integer here is really important! */
@@ -131,10 +127,10 @@
if (bits_used > budget)
{qi = -1;
- error[i+c*m->nbEBands] = 128;
+ error[i+c*m->nbEBands] = QCONST16(.5f,DB_SHIFT);
} else {ec_laplace_encode_start(enc, &qi, prob[2*i], prob[2*i+1]);
- error[i+c*m->nbEBands] = f - SHL16(qi,8);
+ error[i+c*m->nbEBands] = f - SHL16(qi,DB_SHIFT);
}
q = SHL16(qi,DB_SHIFT);
@@ -162,7 +158,7 @@
celt_word16 offset;
#ifdef FIXED_POINT
/* Has to be without rounding */
- q2 = (error[i+c*m->nbEBands]+QCONST16(.5f,8))>>(8-fine_quant[i]);
+ q2 = (error[i+c*m->nbEBands]+QCONST16(.5f,DB_SHIFT))>>(DB_SHIFT-fine_quant[i]);
#else
q2 = (int)floor((error[i+c*m->nbEBands]+.5f)*frac);
#endif
@@ -170,7 +166,7 @@
q2 = frac-1;
ec_enc_bits(enc, q2, fine_quant[i]);
#ifdef FIXED_POINT
- offset = SUB16(SHR16(SHL16(q2,8)+QCONST16(.5,8),fine_quant[i]),QCONST16(.5f,8));
+ offset = SUB16(SHR16(SHL16(q2,DB_SHIFT)+QCONST16(.5,DB_SHIFT),fine_quant[i]),QCONST16(.5f,DB_SHIFT));
#else
offset = (q2+.5f)*(1<<(14-fine_quant[i]))*(1.f/16384) - .5f;
#endif
@@ -203,7 +199,7 @@
q2 = error[i+c*m->nbEBands]<0 ? 0 : 1;
ec_enc_bits(enc, q2, 1);
#ifdef FIXED_POINT
- offset = SHR16(SHL16(q2,8)-QCONST16(.5,8),fine_quant[i]+1);
+ offset = SHR16(SHL16(q2,DB_SHIFT)-QCONST16(.5,DB_SHIFT),fine_quant[i]+1);
#else
offset = (q2-.5f)*(1<<(14-fine_quant[i]-1))*(1.f/16384);
#endif
@@ -215,8 +211,8 @@
for (i=start;i<C*m->nbEBands;i++)
{eBands[i] = log2Amp(oldEBands[i]);
- if (oldEBands[i] < -QCONST16(7.f,8))
- oldEBands[i] = -QCONST16(7.f,8);
+ if (oldEBands[i] < -QCONST16(7.f,DB_SHIFT))
+ oldEBands[i] = -QCONST16(7.f,DB_SHIFT);
}
}
@@ -253,7 +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_Q15(Q15ONE-beta,q);
+ prev[c] = mean+prev[c]+MULT16_16_P15(Q15ONE-beta,q);
} while (++c < C);
}
}
@@ -273,7 +269,7 @@
celt_word16 offset;
q2 = ec_dec_bits(dec, fine_quant[i]);
#ifdef FIXED_POINT
- offset = SUB16(SHR16(SHL16(q2,8)+QCONST16(.5,8),fine_quant[i]),QCONST16(.5f,8));
+ offset = SUB16(SHR16(SHL16(q2,DB_SHIFT)+QCONST16(.5,DB_SHIFT),fine_quant[i]),QCONST16(.5f,DB_SHIFT));
#else
offset = (q2+.5f)*(1<<(14-fine_quant[i]))*(1.f/16384) - .5f;
#endif
@@ -302,7 +298,7 @@
celt_word16 offset;
q2 = ec_dec_bits(dec, 1);
#ifdef FIXED_POINT
- offset = SHR16(SHL16(q2,8)-QCONST16(.5,8),fine_quant[i]+1);
+ offset = SHR16(SHL16(q2,DB_SHIFT)-QCONST16(.5,DB_SHIFT),fine_quant[i]+1);
#else
offset = (q2-.5f)*(1<<(14-fine_quant[i]-1))*(1.f/16384);
#endif
@@ -314,7 +310,7 @@
for (i=start;i<C*m->nbEBands;i++)
{eBands[i] = log2Amp(oldEBands[i]);
- if (oldEBands[i] < -QCONST16(7.f,8))
- oldEBands[i] = -QCONST16(7.f,8);
+ if (oldEBands[i] < -QCONST16(7.f,DB_SHIFT))
+ oldEBands[i] = -QCONST16(7.f,DB_SHIFT);
}
}
--- a/libcelt/quant_bands.h
+++ b/libcelt/quant_bands.h
@@ -46,7 +46,7 @@
static inline celt_word32 log2Amp(celt_word16 lg)
{- return PSHR32(celt_exp2(SHL16(lg,3)),4);
+ return PSHR32(celt_exp2(SHL16(lg,11-DB_SHIFT)),4);
}
int *quant_prob_alloc(const CELTMode *m);