opus/libcelt/rate.c
2008-01-17 14:07:55 +11:00

315 lines
8.2 KiB
C

/* (C) 2007 Jean-Marc Valin, CSIRO
*/
/*
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
- Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
- Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
- Neither the name of the Xiph.org Foundation nor the names of its
contributors may be used to endorse or promote products derived from
this software without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR
CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <math.h>
#include "modes.h"
#include "cwrs.h"
#include "arch.h"
#include "os_support.h"
#include "entcode.h"
#include "rate.h"
#define BITRES 4
#define BITROUND 8
#define BITOVERFLOW 10000
#define MAX_PULSES 64
int log2_frac(ec_uint32 val, int frac)
{
int i;
/* EC_ILOG() actually returns log2()+1, go figure */
int L = EC_ILOG(val)-1;
//printf ("in: %d %d ", val, L);
if (L>14)
val >>= L-14;
else if (L<14)
val <<= 14-L;
L <<= frac;
//printf ("%d\n", val);
for (i=0;i<frac;i++)
{
val = (val*val) >> 15;
//printf ("%d\n", val);
if (val > 16384)
L |= (1<<(frac-i-1));
else
val <<= 1;
}
return L;
}
int log2_frac64(ec_uint64 val, int frac)
{
int i;
/* EC_ILOG64() actually returns log2()+1, go figure */
int L = EC_ILOG64(val)-1;
//printf ("in: %d %d ", val, L);
if (L>14)
val >>= L-14;
else if (L<14)
val <<= 14-L;
L <<= frac;
//printf ("%d\n", val);
for (i=0;i<frac;i++)
{
val = (val*val) >> 15;
//printf ("%d\n", val);
if (val > 16384)
L |= (1<<(frac-i-1));
else
val <<= 1;
}
return L;
}
void alloc_init(struct alloc_data *alloc, const CELTMode *m)
{
int i, prevN, BC;
const int *eBands = m->eBands;
alloc->mode = m;
alloc->len = m->nbEBands;
alloc->bands = m->eBands;
alloc->bits = celt_alloc(m->nbEBands*sizeof(int*));
BC = m->nbMdctBlocks*m->nbChannels;
prevN = -1;
for (i=0;i<alloc->len;i++)
{
int N = BC*(eBands[i+1]-eBands[i]);
if (N == prevN)
{
alloc->bits[i] = alloc->bits[i-1];
} else {
int j;
/* FIXME: We could save memory here */
alloc->bits[i] = celt_alloc(MAX_PULSES*sizeof(int));
for (j=0;j<MAX_PULSES;j++)
{
alloc->bits[i][j] = log2_frac64(ncwrs64(N, j),BITRES);
/* We could just update rev_bits here */
if (alloc->bits[i][j] > (60<<BITRES))
break;
}
for (;j<MAX_PULSES;j++)
alloc->bits[i][j] = BITOVERFLOW;
prevN = N;
}
}
}
void alloc_clear(struct alloc_data *alloc)
{
int i;
int *prevPtr = NULL;
for (i=0;i<alloc->len;i++)
{
if (alloc->bits[i] != prevPtr)
{
prevPtr = alloc->bits[i];
celt_free(alloc->bits[i]);
}
}
celt_free(alloc->bits);
}
int bits2pulses(const struct alloc_data *alloc, int band, int bits)
{
int lo, hi;
lo = 0;
hi = MAX_PULSES-1;
while (hi-lo != 1)
{
int mid = (lo+hi)>>1;
if (alloc->bits[band][mid] >= bits)
hi = mid;
else
lo = mid;
}
if (bits-alloc->bits[band][lo] <= alloc->bits[band][hi]-bits)
return lo;
else
return hi;
}
int vec_bits2pulses(const struct alloc_data *alloc, const int *bands, int *bits, int *pulses, int len)
{
int i, BC;
int sum=0;
BC = alloc->mode->nbMdctBlocks*alloc->mode->nbChannels;
for (i=0;i<len;i++)
{
int N = (bands[i+1]-bands[i])*BC;
pulses[i] = bits2pulses(alloc, i, bits[i]);
sum += alloc->bits[i][pulses[i]];
}
//printf ("sum = %d\n", sum);
return sum;
}
int interp_bits2pulses(const struct alloc_data *alloc, int *bits1, int *bits2, int total, int *pulses, int len)
{
int lo, hi, out;
int j;
int bits[len];
const int *bands = alloc->bands;
lo = 0;
hi = 1<<BITRES;
while (hi-lo != 1)
{
int mid = (lo+hi)>>1;
for (j=0;j<len;j++)
bits[j] = ((1<<BITRES)-mid)*bits1[j] + mid*bits2[j];
if (vec_bits2pulses(alloc, bands, bits, pulses, len) > total<<BITRES)
hi = mid;
else
lo = mid;
}
//printf ("interp bisection gave %d\n", lo);
for (j=0;j<len;j++)
bits[j] = ((1<<BITRES)-lo)*bits1[j] + lo*bits2[j];
out = vec_bits2pulses(alloc, bands, bits, pulses, len);
/* Do some refinement to use up all bits */
while(1)
{
int incremented = 0;
for (j=0;j<len;j++)
{
if (alloc->bits[j][pulses[j]] < bits[j] && pulses[j]<MAX_PULSES-1)
{
if (out+alloc->bits[j][pulses[j]+1]-alloc->bits[j][pulses[j]] <= total<<BITRES)
{
out = out+alloc->bits[j][pulses[j]+1]-alloc->bits[j][pulses[j]];
pulses[j] += 1;
incremented = 1;
//printf ("INCREMENT %d\n", j);
}
}
}
if (!incremented)
break;
}
return (out+BITROUND) >> BITRES;
}
int compute_allocation(const struct alloc_data *alloc, int *offsets, int total, int *pulses)
{
int lo, hi, len;
const CELTMode *m;
m = alloc->mode;
len = m->nbEBands;
lo = 0;
hi = m->nbAllocVectors - 1;
while (hi-lo != 1)
{
int j;
int bits[len];
int pulses[len];
int mid = (lo+hi) >> 1;
for (j=0;j<len;j++)
{
bits[j] = (m->allocVectors[mid*len+j] + offsets[j])<<BITRES;
if (bits[j] < 0)
bits[j] = 0;
//printf ("%d ", bits[j]);
}
//printf ("\n");
if (vec_bits2pulses(alloc, alloc->bands, bits, pulses, len) > total<<BITRES)
hi = mid;
else
lo = mid;
//printf ("lo = %d, hi = %d\n", lo, hi);
}
{
int bits1[len];
int bits2[len];
int j;
for (j=0;j<len;j++)
{
bits1[j] = m->allocVectors[lo*len+j] + offsets[j];
bits2[j] = m->allocVectors[hi*len+j] + offsets[j];
if (bits1[j] < 0)
bits1[j] = 0;
if (bits2[j] < 0)
bits2[j] = 0;
}
return interp_bits2pulses(alloc, bits1, bits2, total, pulses, len);
}
}
#if 0
int main()
{
int i;
printf ("log(128) = %d\n", EC_ILOG(128));
for(i=1;i<2000000000;i+=1738)
{
printf ("%d %d\n", i, log2_frac(i, 10));
}
return 0;
}
#endif
#if 0
int main()
{
int i;
int offsets[18] = {0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
int bits[18] = {10, 9, 9, 8, 8, 8, 8, 8, 8, 8, 9, 10, 8, 9, 10, 11, 6, 7};
int bits1[18] = {8, 7, 7, 6, 6, 6, 5, 4, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5};
int bits2[18] = {15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15, 15};
int bank[20] = {0, 4, 8, 12, 16, 20, 24, 28, 32, 38, 44, 52, 62, 74, 90,112,142,182, 232,256};
int pulses[18];
struct alloc_data alloc;
alloc_init(&alloc, celt_mode0);
int b;
//b = vec_bits2pulses(&alloc, bank, bits, pulses, 18);
//printf ("total: %d bits\n", b);
//for (i=0;i<18;i++)
// printf ("%d ", pulses[i]);
//printf ("\n");
//b = interp_bits2pulses(&alloc, bits1, bits2, 162, pulses, 18);
b = compute_allocation(&alloc, offsets, 190, pulses);
printf ("total: %d bits\n", b);
for (i=0;i<18;i++)
printf ("%d ", pulses[i]);
printf ("\n");
alloc_clear(&alloc);
return 0;
}
#endif