Bit allocation wotk.

Mimimum resolution is now 1/4 bit/sample instead of 3/8. The allocation
tilt now gives more LF bits for small frame sizes. There's also a new
"alternate" allocation that should soon replace the current one.
This commit is contained in:
Jean-Marc Valin 2010-11-19 11:45:37 -05:00
parent 0722c16dd3
commit 54d84c0130
2 changed files with 14 additions and 42 deletions

View file

@ -65,50 +65,21 @@ static const unsigned char band_allocation[] = {
#else #else
#if 1 /* Alternate tuning (partially derived from Vorbis) */
/* Alternate tuning based on exp_tuning_knobs from 2010/10/21:
87 5 25 14 300
120 5 25 16 400
125 5 25 17 500
130 5 24 18 600
130 5 24 19 920
140 7 24 20 1240
170 7 20 21 2000
120 5 20 21 4000
*/
#define BITALLOC_SIZE 9 #define BITALLOC_SIZE 9
/* Bit allocation table in units of 1/32 bit/sample (0.1875 dB SNR) */ /* Bit allocation table in units of 1/32 bit/sample (0.1875 dB SNR) */
static const unsigned char band_allocation[] = { static const unsigned char band_allocation[] = {
/*0 200 400 600 800 1k 1.2 1.4 1.6 2k 2.4 2.8 3.2 4k 4.8 5.6 6.8 8k 9.6 12k 15.6 */
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
99, 99, 90, 84, 78, 71, 65, 58, 51, 45, 39, 32, 26, 20, 1, 0, 0, 0, 0, 0, 0, 110,100, 90, 84, 78, 71, 65, 58, 51, 45, 39, 32, 26, 20, 12, 0, 0, 0, 0, 0, 0,
124,124,109, 98, 88, 77, 71, 65, 59, 52, 46, 40, 34, 27, 21, 15, 1, 0, 0, 0, 0, 124,116,109, 98, 88, 77, 71, 65, 59, 52, 46, 40, 34, 27, 21, 15, 12, 0, 0, 0, 0,
132,132,117,107, 97, 87, 80, 74, 68, 62, 55, 49, 43, 37, 30, 23, 17, 1, 1, 0, 0, 132,125,117,107, 97, 87, 80, 74, 68, 62, 55, 49, 43, 37, 30, 23, 17, 12, 1, 0, 0,
138,138,123,112,102, 91, 85, 79, 73, 67, 61, 55, 49, 43, 37, 31, 25, 19, 1, 0, 0, 134,127,120,114,103, 97, 91, 85, 78, 72, 66, 60, 54, 47, 41, 35, 29, 23, 16, 10, 1,
152,152,139,130,120,110,104, 98, 92, 86, 80, 74, 68, 62, 56, 50, 44, 38, 32, 8, 0, 144,137,130,124,113,107,101, 95, 88, 82, 76, 70, 64, 57, 51, 45, 39, 33, 26, 20, 2,
167,167,154,145,136,127,117,108,102, 96, 90, 84, 78, 72, 66, 60, 54, 48, 42, 36, 2, 152,145,138,132,123,117,111,105, 98, 92, 86, 80, 74, 67, 61, 55, 49, 43, 36, 30, 4,
215,215,194,180,165,151,137,121,116,111,106,101, 96, 91, 86, 81, 76, 71, 66, 61, 56, 172,165,158,152,143,137,131,125,118,112,106,100, 94, 87, 81, 75, 69, 63, 56, 50, 12,
240,240,239,233,225,218,211,203,198,193,188,183,178,173,168,163,158,153,148,143,138, 200,200,200,200,200,200,200,200,198,193,188,183,178,173,168,163,158,153,148,143,138,
}; };
#else
/* Alternate tuning (partially derived from Vorbis) */
#define BITALLOC_SIZE 11
/* Bit allocation table in units of 1/32 bit/sample (0.1875 dB SNR) */
static const unsigned char band_allocation[] = {
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
85, 85, 75, 70, 63, 55, 50, 45, 40, 35, 33, 28, 15, 1, 0, 0, 0, 0, 0, 0, 0,
108,105, 96, 88, 83, 77, 72, 66, 59, 53, 49, 44, 41, 37, 30, 27, 1, 0, 0, 0, 0,
120,117,108,100, 95, 89, 84, 78, 71, 65, 61, 56, 53, 49, 42, 34, 30, 25, 1, 0, 0,
136,131,123,118,109, 99, 93, 87, 81, 75, 69, 66, 61, 56, 50, 45, 40, 35, 32, 1, 1,
151,148,138,131,122,113,105,102, 96, 92, 85, 82, 76, 68, 63, 58, 51, 44, 38, 27, 8,
171,168,158,147,139,130,123,119,111,108,103, 99, 91, 82, 78, 75, 66, 55, 48, 36, 12,
187,184,174,163,155,146,139,135,127,124,119,115,107, 98, 94, 91, 82, 71, 64, 52, 28,
203,200,191,181,174,166,159,156,149,147,143,139,132,124,121,119,110,100, 94, 83, 60,
219,216,207,197,190,183,176,173,166,164,161,157,150,142,139,138,129,119,113,102, 80,
229,229,224,222,223,224,224,225,222,221,221,220,220,219,218,200,178,154,146,130,102,
};
#endif
#endif #endif
#ifdef STATIC_MODES #ifdef STATIC_MODES

View file

@ -155,7 +155,7 @@ static inline int interp_bits2pulses(const CELTMode *m, int start, int end, int
/* Threshold: don't allow any band to go below 3/8 bit/sample */ /* Threshold: don't allow any band to go below 3/8 bit/sample */
for (j=start;j<end;j++) for (j=start;j<end;j++)
thresh[j] = 3*(C*(m->eBands[j+1]-m->eBands[j])<<LM<<BITRES)>>3; thresh[j] = 2*(C*(m->eBands[j+1]-m->eBands[j])<<LM<<BITRES)>>3;
logM = LM<<BITRES; logM = LM<<BITRES;
lo = 0; lo = 0;
hi = 1<<ALLOC_STEPS; hi = 1<<ALLOC_STEPS;
@ -203,6 +203,7 @@ static inline int interp_bits2pulses(const CELTMode *m, int start, int end, int
for (j=start;j<start+left;j++) for (j=start;j<start+left;j++)
bits[j]++; bits[j]++;
} }
/*for (j=0;j<end;j++)printf("%d ", bits[j]);printf("\n");*/
for (j=start;j<end;j++) for (j=start;j<end;j++)
{ {
int N0, N, den; int N0, N, den;
@ -281,10 +282,10 @@ int compute_allocation(const CELTMode *m, int start, int end, int *offsets, int
/* Below this threshold, we don't allocate any PVQ bits */ /* Below this threshold, we don't allocate any PVQ bits */
for (j=start;j<end;j++) for (j=start;j<end;j++)
thresh[j] = 3*(C*(m->eBands[j+1]-m->eBands[j])<<LM<<BITRES)>>3; thresh[j] = 2*(C*(m->eBands[j+1]-m->eBands[j])<<LM<<BITRES)>>3;
/* Tilt of the allocation curve */ /* Tilt of the allocation curve */
for (j=start;j<end;j++) for (j=start;j<end;j++)
trim_offset[j] = C*(m->eBands[j+1]-m->eBands[j])*(2*alloc_trim-7)*(m->nbEBands-j-1) trim_offset[j] = C*(m->eBands[j+1]-m->eBands[j])*(2*alloc_trim-4-LM)*(m->nbEBands-j-1)
<<(LM+BITRES)>>6; <<(LM+BITRES)>>6;
lo = 0; lo = 0;