ref: 9c70906fdb55c668a9d2c397de300f56d828dc05
parent: 36e6e01adabc74b79020c1c56292d02ea209d601
author: Jean-Marc Valin <[email protected]>
date: Sun Aug 3 18:07:06 EDT 2008
Changing the allocation algorithm to better take into account the fixed cost per frames for each mode.
--- a/libcelt/celt.c
+++ b/libcelt/celt.c
@@ -533,7 +533,7 @@
ALLOC(fine_quant, st->mode->nbEBands, int);
ALLOC(error, C*st->mode->nbEBands, celt_word16_t);
- quant_coarse_energy(st->mode, bandE, st->oldBandE, 20*C+nbCompressedBytes*8, st->mode->prob, error, &st->enc);
+ quant_coarse_energy(st->mode, bandE, st->oldBandE, nbCompressedBytes*8/3, st->mode->prob, error, &st->enc);
ALLOC(pulses, st->mode->nbEBands, int);
ALLOC(offsets, st->mode->nbEBands, int);
@@ -838,7 +838,7 @@
ALLOC(fine_quant, st->mode->nbEBands, int);
/* Get band energies */
- unquant_coarse_energy(st->mode, bandE, st->oldBandE, 20*C+len*8, st->mode->prob, &dec);
+ unquant_coarse_energy(st->mode, bandE, st->oldBandE, len*8/3, st->mode->prob, &dec);
ALLOC(pulses, st->mode->nbEBands, int);
ALLOC(offsets, st->mode->nbEBands, int);
--- a/libcelt/modes.c
+++ b/libcelt/modes.c
@@ -104,9 +104,10 @@
int BITALLOC_SIZE;
int *band_allocation;
#else
-#define BITALLOC_SIZE 11
+#define BITALLOC_SIZE 12
static const int band_allocation[BARK_BANDS*BITALLOC_SIZE] =
- { 2, 2, 1, 1, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,+ { 4, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,+ 2, 2, 1, 1, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
2, 2, 2, 1, 2, 2, 2, 2, 2, 1, 2, 2, 4, 5, 7, 7, 7, 5, 4, 0, 0, 0, 0, 0, 0,
2, 2, 2, 2, 3, 2, 2, 2, 2, 2, 3, 3, 5, 6, 8, 8, 8, 6, 5, 4, 0, 0, 0, 0, 0,
3, 2, 2, 2, 3, 3, 2, 3, 2, 3, 4, 4, 6, 7, 9, 9, 9, 7, 6, 5, 5, 5, 0, 0, 0,
@@ -235,22 +236,22 @@
for (i=0;i<mode->nbAllocVectors;i++)
{int sum = 0;
- int min_bits = 1;
- if (allocVectors[i*mode->nbEBands]>12)
- min_bits = 2;
- if (allocVectors[i*mode->nbEBands]>24)
- min_bits = 3;
for (j=0;j<mode->nbEBands;j++)
{- allocEnergy[i*(mode->nbEBands+1)+j] = allocVectors[i*mode->nbEBands+j]
- / (C*(mode->eBands[j+1]-mode->eBands[j]));
- if (allocEnergy[i*(mode->nbEBands+1)+j]<min_bits)
- allocEnergy[i*(mode->nbEBands+1)+j] = min_bits;
- if (allocEnergy[i*(mode->nbEBands+1)+j]>7)
- allocEnergy[i*(mode->nbEBands+1)+j] = 7;
+ int ebits;
+ int min_bits=0;
+ if (allocVectors[i*mode->nbEBands+j] >= C)
+ min_bits = 1;
+ ebits = allocVectors[i*mode->nbEBands+j] / (C*(mode->eBands[j+1]-mode->eBands[j]));
+ if (ebits<min_bits)
+ ebits = min_bits;
/* The bits used for fine allocation can't be used for pulses */
- allocVectors[i*mode->nbEBands+j] -= C*allocEnergy[i*(mode->nbEBands+1)+j];
- sum += allocEnergy[i*(mode->nbEBands+1)+j];
+ /* However, we give two "free" bits to all modes to compensate for the fact that some energy
+ resolution is needed regardless of the frame size. */
+ if (ebits>1)
+ allocVectors[i*mode->nbEBands+j] -= C*(ebits-2);
+ sum += ebits;
+ allocEnergy[i*(mode->nbEBands+1)+j] = ebits;
}
allocEnergy[i*(mode->nbEBands+1)+mode->nbEBands] = sum;
}
--- a/libcelt/quant_bands.c
+++ b/libcelt/quant_bands.c
@@ -129,7 +129,7 @@
#endif
/* If we don't have enough bits to encode all the energy, just assume something safe.
We allow slightly busting the budget here */
- if (ec_enc_tell(enc, 0) - bits > budget+16)
+ if (ec_enc_tell(enc, 0) - bits > budget)
qi = -1;
else
ec_laplace_encode_start(enc, &qi, prob[2*i], prob[2*i+1]);
@@ -194,7 +194,7 @@
celt_word16_t mean = MULT16_16_Q15(Q15ONE-coef,eMeans[i]);
/* 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) - bits > budget+16)
+ if (ec_dec_tell(dec, 0) - bits > budget)
qi = -1;
else
qi = ec_laplace_decode_start(dec, prob[2*i], prob[2*i+1]);