ref: de67858765a7b23e2cb31eead26b400937ff2d0b
dir: /libcelt/rate.h/
/* (C) 2007-2008 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.
*/
#ifndef RATE_H
#define RATE_H
#define MAX_PSEUDO 40
#define LOG_MAX_PSEUDO 6
#define MAX_PULSES 128
#define LOG_MAX_PULSES 7
#define BITRES 4
#define FINE_OFFSET 50
#define QTHETA_OFFSET 40
#define BITOVERFLOW 30000
#include "cwrs.h"
static inline int get_pulses(int i)
{
return i<8 ? i : (8 + (i&7)) << ((i>>3)-1);
}
static inline int bits2pulses(const CELTMode *m, const celt_int16_t *cache, int N, int bits)
{
int i;
int lo, hi;
lo = 0;
hi = MAX_PSEUDO-1;
for (i=0;i<LOG_MAX_PSEUDO;i++)
{
int mid = (lo+hi)>>1;
/* OPT: Make sure this is implemented with a conditional move */
if (cache[mid] >= bits)
hi = mid;
else
lo = mid;
}
if (bits-cache[lo] <= cache[hi]-bits)
return lo;
else
return hi;
lo = 0;
hi = MAX_PULSES-1;
#if 0 /* Disabled until we can make that useful */
/* Use of more than MAX_PULSES is disabled until we are able to cwrs that decently */
if (bits > cache[MAX_PULSES-1] && N<=4)
{
/*int pulses;
pulses = 127;
while (16 + log2_frac(2*(pulses+1)*(pulses+1) + 1, 4) <= bits && pulses < 32767)
pulses++;*/
lo = 127;
switch (N)
{
case 3:
hi = 1024;
for (i=0;i<10;i++)
{
int pulses = (lo+hi)>>1;
if (log2_frac(((UMUL16_16(pulses,pulses)>>1)+1)>>1, 4) > bits)
hi = pulses;
else
lo = pulses;
}
break;
case 4:
hi = 1024;
for (i=0;i<10;i++)
{
int pulses = (lo+hi)>>1;
if (log2_frac((UMUL32(UMUL16_16(pulses,pulses)+2,pulses))/3<<3, 4) > bits)
hi = pulses;
else
lo = pulses;
}
break;
}
return lo;
}
#endif
/* Instead of using the "bisection condition" we use a fixed number of
iterations because it should be faster */
/*while (hi-lo != 1)*/
for (i=0;i<LOG_MAX_PULSES;i++)
{
int mid = (lo+hi)>>1;
/* OPT: Make sure this is implemented with a conditional move */
if (cache[mid] >= bits)
hi = mid;
else
lo = mid;
}
if (bits-cache[lo] <= cache[hi]-bits)
return lo;
else
return hi;
}
static inline int pulses2bits(const celt_int16_t *cache, int N, int pulses)
{
#if 0 /* Use of more than MAX_PULSES is disabled until we are able to cwrs that decently */
if (pulses > 127)
{
int bits;
switch (N)
{
case 3:
bits = log2_frac(((UMUL16_16(pulses,pulses)>>1)+1)>>1, 4);
break;
case 4:
bits = log2_frac((UMUL32(UMUL16_16(pulses,pulses)+2,pulses))/3<<3, 4);
break;
}
/*printf ("%d <- %d\n", bits, pulses);*/
return bits;
}
#endif
return cache[pulses];
}
/** Computes a cache of the pulses->bits mapping in each band */
celt_int16_t **compute_alloc_cache(CELTMode *m, int C);
/** Compute the pulse allocation, i.e. how many pulses will go in each
* band.
@param m mode
@param offsets Requested increase or decrease in the number of bits for
each band
@param total Number of bands
@param pulses Number of pulses per band (returned)
@return Total number of bits allocated
*/
void compute_allocation(const CELTMode *m, int *offsets, int total, int *pulses, int *ebits, int *fine_priority);
#endif