Chris@69: /* Copyright (c) 2007-2008 CSIRO
Chris@69:    Copyright (c) 2007-2009 Xiph.Org Foundation
Chris@69:    Written by Jean-Marc Valin */
Chris@69: /*
Chris@69:    Redistribution and use in source and binary forms, with or without
Chris@69:    modification, are permitted provided that the following conditions
Chris@69:    are met:
Chris@69: 
Chris@69:    - Redistributions of source code must retain the above copyright
Chris@69:    notice, this list of conditions and the following disclaimer.
Chris@69: 
Chris@69:    - Redistributions in binary form must reproduce the above copyright
Chris@69:    notice, this list of conditions and the following disclaimer in the
Chris@69:    documentation and/or other materials provided with the distribution.
Chris@69: 
Chris@69:    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
Chris@69:    ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
Chris@69:    LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
Chris@69:    A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
Chris@69:    OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
Chris@69:    EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
Chris@69:    PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
Chris@69:    PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
Chris@69:    LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
Chris@69:    NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
Chris@69:    SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
Chris@69: */
Chris@69: 
Chris@69: #ifdef HAVE_CONFIG_H
Chris@69: #include "config.h"
Chris@69: #endif
Chris@69: 
Chris@69: #include <math.h>
Chris@69: #include "modes.h"
Chris@69: #include "cwrs.h"
Chris@69: #include "arch.h"
Chris@69: #include "os_support.h"
Chris@69: 
Chris@69: #include "entcode.h"
Chris@69: #include "rate.h"
Chris@69: 
Chris@69: static const unsigned char LOG2_FRAC_TABLE[24]={
Chris@69:    0,
Chris@69:    8,13,
Chris@69:   16,19,21,23,
Chris@69:   24,26,27,28,29,30,31,32,
Chris@69:   32,33,34,34,35,36,36,37,37
Chris@69: };
Chris@69: 
Chris@69: #ifdef CUSTOM_MODES
Chris@69: 
Chris@69: /*Determines if V(N,K) fits in a 32-bit unsigned integer.
Chris@69:   N and K are themselves limited to 15 bits.*/
Chris@69: static int fits_in32(int _n, int _k)
Chris@69: {
Chris@69:    static const opus_int16 maxN[15] = {
Chris@69:       32767, 32767, 32767, 1476, 283, 109,  60,  40,
Chris@69:        29,  24,  20,  18,  16,  14,  13};
Chris@69:    static const opus_int16 maxK[15] = {
Chris@69:       32767, 32767, 32767, 32767, 1172, 238,  95,  53,
Chris@69:        36,  27,  22,  18,  16,  15,  13};
Chris@69:    if (_n>=14)
Chris@69:    {
Chris@69:       if (_k>=14)
Chris@69:          return 0;
Chris@69:       else
Chris@69:          return _n <= maxN[_k];
Chris@69:    } else {
Chris@69:       return _k <= maxK[_n];
Chris@69:    }
Chris@69: }
Chris@69: 
Chris@69: void compute_pulse_cache(CELTMode *m, int LM)
Chris@69: {
Chris@69:    int C;
Chris@69:    int i;
Chris@69:    int j;
Chris@69:    int curr=0;
Chris@69:    int nbEntries=0;
Chris@69:    int entryN[100], entryK[100], entryI[100];
Chris@69:    const opus_int16 *eBands = m->eBands;
Chris@69:    PulseCache *cache = &m->cache;
Chris@69:    opus_int16 *cindex;
Chris@69:    unsigned char *bits;
Chris@69:    unsigned char *cap;
Chris@69: 
Chris@69:    cindex = (opus_int16 *)opus_alloc(sizeof(cache->index[0])*m->nbEBands*(LM+2));
Chris@69:    cache->index = cindex;
Chris@69: 
Chris@69:    /* Scan for all unique band sizes */
Chris@69:    for (i=0;i<=LM+1;i++)
Chris@69:    {
Chris@69:       for (j=0;j<m->nbEBands;j++)
Chris@69:       {
Chris@69:          int k;
Chris@69:          int N = (eBands[j+1]-eBands[j])<<i>>1;
Chris@69:          cindex[i*m->nbEBands+j] = -1;
Chris@69:          /* Find other bands that have the same size */
Chris@69:          for (k=0;k<=i;k++)
Chris@69:          {
Chris@69:             int n;
Chris@69:             for (n=0;n<m->nbEBands && (k!=i || n<j);n++)
Chris@69:             {
Chris@69:                if (N == (eBands[n+1]-eBands[n])<<k>>1)
Chris@69:                {
Chris@69:                   cindex[i*m->nbEBands+j] = cindex[k*m->nbEBands+n];
Chris@69:                   break;
Chris@69:                }
Chris@69:             }
Chris@69:          }
Chris@69:          if (cache->index[i*m->nbEBands+j] == -1 && N!=0)
Chris@69:          {
Chris@69:             int K;
Chris@69:             entryN[nbEntries] = N;
Chris@69:             K = 0;
Chris@69:             while (fits_in32(N,get_pulses(K+1)) && K<MAX_PSEUDO)
Chris@69:                K++;
Chris@69:             entryK[nbEntries] = K;
Chris@69:             cindex[i*m->nbEBands+j] = curr;
Chris@69:             entryI[nbEntries] = curr;
Chris@69: 
Chris@69:             curr += K+1;
Chris@69:             nbEntries++;
Chris@69:          }
Chris@69:       }
Chris@69:    }
Chris@69:    bits = (unsigned char *)opus_alloc(sizeof(unsigned char)*curr);
Chris@69:    cache->bits = bits;
Chris@69:    cache->size = curr;
Chris@69:    /* Compute the cache for all unique sizes */
Chris@69:    for (i=0;i<nbEntries;i++)
Chris@69:    {
Chris@69:       unsigned char *ptr = bits+entryI[i];
Chris@69:       opus_int16 tmp[CELT_MAX_PULSES+1];
Chris@69:       get_required_bits(tmp, entryN[i], get_pulses(entryK[i]), BITRES);
Chris@69:       for (j=1;j<=entryK[i];j++)
Chris@69:          ptr[j] = tmp[get_pulses(j)]-1;
Chris@69:       ptr[0] = entryK[i];
Chris@69:    }
Chris@69: 
Chris@69:    /* Compute the maximum rate for each band at which we'll reliably use as
Chris@69:        many bits as we ask for. */
Chris@69:    cache->caps = cap = (unsigned char *)opus_alloc(sizeof(cache->caps[0])*(LM+1)*2*m->nbEBands);
Chris@69:    for (i=0;i<=LM;i++)
Chris@69:    {
Chris@69:       for (C=1;C<=2;C++)
Chris@69:       {
Chris@69:          for (j=0;j<m->nbEBands;j++)
Chris@69:          {
Chris@69:             int N0;
Chris@69:             int max_bits;
Chris@69:             N0 = m->eBands[j+1]-m->eBands[j];
Chris@69:             /* N=1 bands only have a sign bit and fine bits. */
Chris@69:             if (N0<<i == 1)
Chris@69:                max_bits = C*(1+MAX_FINE_BITS)<<BITRES;
Chris@69:             else
Chris@69:             {
Chris@69:                const unsigned char *pcache;
Chris@69:                opus_int32           num;
Chris@69:                opus_int32           den;
Chris@69:                int                  LM0;
Chris@69:                int                  N;
Chris@69:                int                  offset;
Chris@69:                int                  ndof;
Chris@69:                int                  qb;
Chris@69:                int                  k;
Chris@69:                LM0 = 0;
Chris@69:                /* Even-sized bands bigger than N=2 can be split one more time.
Chris@69:                   As of commit 44203907 all bands >1 are even, including custom modes.*/
Chris@69:                if (N0 > 2)
Chris@69:                {
Chris@69:                   N0>>=1;
Chris@69:                   LM0--;
Chris@69:                }
Chris@69:                /* N0=1 bands can't be split down to N<2. */
Chris@69:                else if (N0 <= 1)
Chris@69:                {
Chris@69:                   LM0=IMIN(i,1);
Chris@69:                   N0<<=LM0;
Chris@69:                }
Chris@69:                /* Compute the cost for the lowest-level PVQ of a fully split
Chris@69:                    band. */
Chris@69:                pcache = bits + cindex[(LM0+1)*m->nbEBands+j];
Chris@69:                max_bits = pcache[pcache[0]]+1;
Chris@69:                /* Add in the cost of coding regular splits. */
Chris@69:                N = N0;
Chris@69:                for(k=0;k<i-LM0;k++){
Chris@69:                   max_bits <<= 1;
Chris@69:                   /* Offset the number of qtheta bits by log2(N)/2
Chris@69:                       + QTHETA_OFFSET compared to their "fair share" of
Chris@69:                       total/N */
Chris@69:                   offset = ((m->logN[j]+((LM0+k)<<BITRES))>>1)-QTHETA_OFFSET;
Chris@69:                   /* The number of qtheta bits we'll allocate if the remainder
Chris@69:                       is to be max_bits.
Chris@69:                      The average measured cost for theta is 0.89701 times qb,
Chris@69:                       approximated here as 459/512. */
Chris@69:                   num=459*(opus_int32)((2*N-1)*offset+max_bits);
Chris@69:                   den=((opus_int32)(2*N-1)<<9)-459;
Chris@69:                   qb = IMIN((num+(den>>1))/den, 57);
Chris@69:                   celt_assert(qb >= 0);
Chris@69:                   max_bits += qb;
Chris@69:                   N <<= 1;
Chris@69:                }
Chris@69:                /* Add in the cost of a stereo split, if necessary. */
Chris@69:                if (C==2)
Chris@69:                {
Chris@69:                   max_bits <<= 1;
Chris@69:                   offset = ((m->logN[j]+(i<<BITRES))>>1)-(N==2?QTHETA_OFFSET_TWOPHASE:QTHETA_OFFSET);
Chris@69:                   ndof = 2*N-1-(N==2);
Chris@69:                   /* The average measured cost for theta with the step PDF is
Chris@69:                       0.95164 times qb, approximated here as 487/512. */
Chris@69:                   num = (N==2?512:487)*(opus_int32)(max_bits+ndof*offset);
Chris@69:                   den = ((opus_int32)ndof<<9)-(N==2?512:487);
Chris@69:                   qb = IMIN((num+(den>>1))/den, (N==2?64:61));
Chris@69:                   celt_assert(qb >= 0);
Chris@69:                   max_bits += qb;
Chris@69:                }
Chris@69:                /* Add the fine bits we'll use. */
Chris@69:                /* Compensate for the extra DoF in stereo */
Chris@69:                ndof = C*N + ((C==2 && N>2) ? 1 : 0);
Chris@69:                /* Offset the number of fine bits by log2(N)/2 + FINE_OFFSET
Chris@69:                    compared to their "fair share" of total/N */
Chris@69:                offset = ((m->logN[j] + (i<<BITRES))>>1)-FINE_OFFSET;
Chris@69:                /* N=2 is the only point that doesn't match the curve */
Chris@69:                if (N==2)
Chris@69:                   offset += 1<<BITRES>>2;
Chris@69:                /* The number of fine bits we'll allocate if the remainder is
Chris@69:                    to be max_bits. */
Chris@69:                num = max_bits+ndof*offset;
Chris@69:                den = (ndof-1)<<BITRES;
Chris@69:                qb = IMIN((num+(den>>1))/den, MAX_FINE_BITS);
Chris@69:                celt_assert(qb >= 0);
Chris@69:                max_bits += C*qb<<BITRES;
Chris@69:             }
Chris@69:             max_bits = (4*max_bits/(C*((m->eBands[j+1]-m->eBands[j])<<i)))-64;
Chris@69:             celt_assert(max_bits >= 0);
Chris@69:             celt_assert(max_bits < 256);
Chris@69:             *cap++ = (unsigned char)max_bits;
Chris@69:          }
Chris@69:       }
Chris@69:    }
Chris@69: }
Chris@69: 
Chris@69: #endif /* CUSTOM_MODES */
Chris@69: 
Chris@69: #define ALLOC_STEPS 6
Chris@69: 
Chris@69: static OPUS_INLINE int interp_bits2pulses(const CELTMode *m, int start, int end, int skip_start,
Chris@69:       const int *bits1, const int *bits2, const int *thresh, const int *cap, opus_int32 total, opus_int32 *_balance,
Chris@69:       int skip_rsv, int *intensity, int intensity_rsv, int *dual_stereo, int dual_stereo_rsv, int *bits,
Chris@69:       int *ebits, int *fine_priority, int C, int LM, ec_ctx *ec, int encode, int prev, int signalBandwidth)
Chris@69: {
Chris@69:    opus_int32 psum;
Chris@69:    int lo, hi;
Chris@69:    int i, j;
Chris@69:    int logM;
Chris@69:    int stereo;
Chris@69:    int codedBands=-1;
Chris@69:    int alloc_floor;
Chris@69:    opus_int32 left, percoeff;
Chris@69:    int done;
Chris@69:    opus_int32 balance;
Chris@69:    SAVE_STACK;
Chris@69: 
Chris@69:    alloc_floor = C<<BITRES;
Chris@69:    stereo = C>1;
Chris@69: 
Chris@69:    logM = LM<<BITRES;
Chris@69:    lo = 0;
Chris@69:    hi = 1<<ALLOC_STEPS;
Chris@69:    for (i=0;i<ALLOC_STEPS;i++)
Chris@69:    {
Chris@69:       int mid = (lo+hi)>>1;
Chris@69:       psum = 0;
Chris@69:       done = 0;
Chris@69:       for (j=end;j-->start;)
Chris@69:       {
Chris@69:          int tmp = bits1[j] + (mid*(opus_int32)bits2[j]>>ALLOC_STEPS);
Chris@69:          if (tmp >= thresh[j] || done)
Chris@69:          {
Chris@69:             done = 1;
Chris@69:             /* Don't allocate more than we can actually use */
Chris@69:             psum += IMIN(tmp, cap[j]);
Chris@69:          } else {
Chris@69:             if (tmp >= alloc_floor)
Chris@69:                psum += alloc_floor;
Chris@69:          }
Chris@69:       }
Chris@69:       if (psum > total)
Chris@69:          hi = mid;
Chris@69:       else
Chris@69:          lo = mid;
Chris@69:    }
Chris@69:    psum = 0;
Chris@69:    /*printf ("interp bisection gave %d\n", lo);*/
Chris@69:    done = 0;
Chris@69:    for (j=end;j-->start;)
Chris@69:    {
Chris@69:       int tmp = bits1[j] + ((opus_int32)lo*bits2[j]>>ALLOC_STEPS);
Chris@69:       if (tmp < thresh[j] && !done)
Chris@69:       {
Chris@69:          if (tmp >= alloc_floor)
Chris@69:             tmp = alloc_floor;
Chris@69:          else
Chris@69:             tmp = 0;
Chris@69:       } else
Chris@69:          done = 1;
Chris@69:       /* Don't allocate more than we can actually use */
Chris@69:       tmp = IMIN(tmp, cap[j]);
Chris@69:       bits[j] = tmp;
Chris@69:       psum += tmp;
Chris@69:    }
Chris@69: 
Chris@69:    /* Decide which bands to skip, working backwards from the end. */
Chris@69:    for (codedBands=end;;codedBands--)
Chris@69:    {
Chris@69:       int band_width;
Chris@69:       int band_bits;
Chris@69:       int rem;
Chris@69:       j = codedBands-1;
Chris@69:       /* Never skip the first band, nor a band that has been boosted by
Chris@69:           dynalloc.
Chris@69:          In the first case, we'd be coding a bit to signal we're going to waste
Chris@69:           all the other bits.
Chris@69:          In the second case, we'd be coding a bit to redistribute all the bits
Chris@69:           we just signaled should be cocentrated in this band. */
Chris@69:       if (j<=skip_start)
Chris@69:       {
Chris@69:          /* Give the bit we reserved to end skipping back. */
Chris@69:          total += skip_rsv;
Chris@69:          break;
Chris@69:       }
Chris@69:       /*Figure out how many left-over bits we would be adding to this band.
Chris@69:         This can include bits we've stolen back from higher, skipped bands.*/
Chris@69:       left = total-psum;
Chris@69:       percoeff = celt_udiv(left, m->eBands[codedBands]-m->eBands[start]);
Chris@69:       left -= (m->eBands[codedBands]-m->eBands[start])*percoeff;
Chris@69:       rem = IMAX(left-(m->eBands[j]-m->eBands[start]),0);
Chris@69:       band_width = m->eBands[codedBands]-m->eBands[j];
Chris@69:       band_bits = (int)(bits[j] + percoeff*band_width + rem);
Chris@69:       /*Only code a skip decision if we're above the threshold for this band.
Chris@69:         Otherwise it is force-skipped.
Chris@69:         This ensures that we have enough bits to code the skip flag.*/
Chris@69:       if (band_bits >= IMAX(thresh[j], alloc_floor+(1<<BITRES)))
Chris@69:       {
Chris@69:          if (encode)
Chris@69:          {
Chris@69:             /*This if() block is the only part of the allocation function that
Chris@69:                is not a mandatory part of the bitstream: any bands we choose to
Chris@69:                skip here must be explicitly signaled.*/
Chris@69:             int depth_threshold;
Chris@69:             /*We choose a threshold with some hysteresis to keep bands from
Chris@69:                fluctuating in and out, but we try not to fold below a certain point. */
Chris@69:             if (codedBands > 17)
Chris@69:                depth_threshold = j<prev ? 7 : 9;
Chris@69:             else
Chris@69:                depth_threshold = 0;
Chris@69: #ifdef FUZZING
Chris@69:             if ((rand()&0x1) == 0)
Chris@69: #else
Chris@69:             if (codedBands<=start+2 || (band_bits > (depth_threshold*band_width<<LM<<BITRES)>>4 && j<=signalBandwidth))
Chris@69: #endif
Chris@69:             {
Chris@69:                ec_enc_bit_logp(ec, 1, 1);
Chris@69:                break;
Chris@69:             }
Chris@69:             ec_enc_bit_logp(ec, 0, 1);
Chris@69:          } else if (ec_dec_bit_logp(ec, 1)) {
Chris@69:             break;
Chris@69:          }
Chris@69:          /*We used a bit to skip this band.*/
Chris@69:          psum += 1<<BITRES;
Chris@69:          band_bits -= 1<<BITRES;
Chris@69:       }
Chris@69:       /*Reclaim the bits originally allocated to this band.*/
Chris@69:       psum -= bits[j]+intensity_rsv;
Chris@69:       if (intensity_rsv > 0)
Chris@69:          intensity_rsv = LOG2_FRAC_TABLE[j-start];
Chris@69:       psum += intensity_rsv;
Chris@69:       if (band_bits >= alloc_floor)
Chris@69:       {
Chris@69:          /*If we have enough for a fine energy bit per channel, use it.*/
Chris@69:          psum += alloc_floor;
Chris@69:          bits[j] = alloc_floor;
Chris@69:       } else {
Chris@69:          /*Otherwise this band gets nothing at all.*/
Chris@69:          bits[j] = 0;
Chris@69:       }
Chris@69:    }
Chris@69: 
Chris@69:    celt_assert(codedBands > start);
Chris@69:    /* Code the intensity and dual stereo parameters. */
Chris@69:    if (intensity_rsv > 0)
Chris@69:    {
Chris@69:       if (encode)
Chris@69:       {
Chris@69:          *intensity = IMIN(*intensity, codedBands);
Chris@69:          ec_enc_uint(ec, *intensity-start, codedBands+1-start);
Chris@69:       }
Chris@69:       else
Chris@69:          *intensity = start+ec_dec_uint(ec, codedBands+1-start);
Chris@69:    }
Chris@69:    else
Chris@69:       *intensity = 0;
Chris@69:    if (*intensity <= start)
Chris@69:    {
Chris@69:       total += dual_stereo_rsv;
Chris@69:       dual_stereo_rsv = 0;
Chris@69:    }
Chris@69:    if (dual_stereo_rsv > 0)
Chris@69:    {
Chris@69:       if (encode)
Chris@69:          ec_enc_bit_logp(ec, *dual_stereo, 1);
Chris@69:       else
Chris@69:          *dual_stereo = ec_dec_bit_logp(ec, 1);
Chris@69:    }
Chris@69:    else
Chris@69:       *dual_stereo = 0;
Chris@69: 
Chris@69:    /* Allocate the remaining bits */
Chris@69:    left = total-psum;
Chris@69:    percoeff = celt_udiv(left, m->eBands[codedBands]-m->eBands[start]);
Chris@69:    left -= (m->eBands[codedBands]-m->eBands[start])*percoeff;
Chris@69:    for (j=start;j<codedBands;j++)
Chris@69:       bits[j] += ((int)percoeff*(m->eBands[j+1]-m->eBands[j]));
Chris@69:    for (j=start;j<codedBands;j++)
Chris@69:    {
Chris@69:       int tmp = (int)IMIN(left, m->eBands[j+1]-m->eBands[j]);
Chris@69:       bits[j] += tmp;
Chris@69:       left -= tmp;
Chris@69:    }
Chris@69:    /*for (j=0;j<end;j++)printf("%d ", bits[j]);printf("\n");*/
Chris@69: 
Chris@69:    balance = 0;
Chris@69:    for (j=start;j<codedBands;j++)
Chris@69:    {
Chris@69:       int N0, N, den;
Chris@69:       int offset;
Chris@69:       int NClogN;
Chris@69:       opus_int32 excess, bit;
Chris@69: 
Chris@69:       celt_assert(bits[j] >= 0);
Chris@69:       N0 = m->eBands[j+1]-m->eBands[j];
Chris@69:       N=N0<<LM;
Chris@69:       bit = (opus_int32)bits[j]+balance;
Chris@69: 
Chris@69:       if (N>1)
Chris@69:       {
Chris@69:          excess = MAX32(bit-cap[j],0);
Chris@69:          bits[j] = bit-excess;
Chris@69: 
Chris@69:          /* Compensate for the extra DoF in stereo */
Chris@69:          den=(C*N+ ((C==2 && N>2 && !*dual_stereo && j<*intensity) ? 1 : 0));
Chris@69: 
Chris@69:          NClogN = den*(m->logN[j] + logM);
Chris@69: 
Chris@69:          /* Offset for the number of fine bits by log2(N)/2 + FINE_OFFSET
Chris@69:             compared to their "fair share" of total/N */
Chris@69:          offset = (NClogN>>1)-den*FINE_OFFSET;
Chris@69: 
Chris@69:          /* N=2 is the only point that doesn't match the curve */
Chris@69:          if (N==2)
Chris@69:             offset += den<<BITRES>>2;
Chris@69: 
Chris@69:          /* Changing the offset for allocating the second and third
Chris@69:              fine energy bit */
Chris@69:          if (bits[j] + offset < den*2<<BITRES)
Chris@69:             offset += NClogN>>2;
Chris@69:          else if (bits[j] + offset < den*3<<BITRES)
Chris@69:             offset += NClogN>>3;
Chris@69: 
Chris@69:          /* Divide with rounding */
Chris@69:          ebits[j] = IMAX(0, (bits[j] + offset + (den<<(BITRES-1))));
Chris@69:          ebits[j] = celt_udiv(ebits[j], den)>>BITRES;
Chris@69: 
Chris@69:          /* Make sure not to bust */
Chris@69:          if (C*ebits[j] > (bits[j]>>BITRES))
Chris@69:             ebits[j] = bits[j] >> stereo >> BITRES;
Chris@69: 
Chris@69:          /* More than that is useless because that's about as far as PVQ can go */
Chris@69:          ebits[j] = IMIN(ebits[j], MAX_FINE_BITS);
Chris@69: 
Chris@69:          /* If we rounded down or capped this band, make it a candidate for the
Chris@69:              final fine energy pass */
Chris@69:          fine_priority[j] = ebits[j]*(den<<BITRES) >= bits[j]+offset;
Chris@69: 
Chris@69:          /* Remove the allocated fine bits; the rest are assigned to PVQ */
Chris@69:          bits[j] -= C*ebits[j]<<BITRES;
Chris@69: 
Chris@69:       } else {
Chris@69:          /* For N=1, all bits go to fine energy except for a single sign bit */
Chris@69:          excess = MAX32(0,bit-(C<<BITRES));
Chris@69:          bits[j] = bit-excess;
Chris@69:          ebits[j] = 0;
Chris@69:          fine_priority[j] = 1;
Chris@69:       }
Chris@69: 
Chris@69:       /* Fine energy can't take advantage of the re-balancing in
Chris@69:           quant_all_bands().
Chris@69:          Instead, do the re-balancing here.*/
Chris@69:       if(excess > 0)
Chris@69:       {
Chris@69:          int extra_fine;
Chris@69:          int extra_bits;
Chris@69:          extra_fine = IMIN(excess>>(stereo+BITRES),MAX_FINE_BITS-ebits[j]);
Chris@69:          ebits[j] += extra_fine;
Chris@69:          extra_bits = extra_fine*C<<BITRES;
Chris@69:          fine_priority[j] = extra_bits >= excess-balance;
Chris@69:          excess -= extra_bits;
Chris@69:       }
Chris@69:       balance = excess;
Chris@69: 
Chris@69:       celt_assert(bits[j] >= 0);
Chris@69:       celt_assert(ebits[j] >= 0);
Chris@69:    }
Chris@69:    /* Save any remaining bits over the cap for the rebalancing in
Chris@69:        quant_all_bands(). */
Chris@69:    *_balance = balance;
Chris@69: 
Chris@69:    /* The skipped bands use all their bits for fine energy. */
Chris@69:    for (;j<end;j++)
Chris@69:    {
Chris@69:       ebits[j] = bits[j] >> stereo >> BITRES;
Chris@69:       celt_assert(C*ebits[j]<<BITRES == bits[j]);
Chris@69:       bits[j] = 0;
Chris@69:       fine_priority[j] = ebits[j]<1;
Chris@69:    }
Chris@69:    RESTORE_STACK;
Chris@69:    return codedBands;
Chris@69: }
Chris@69: 
Chris@69: int clt_compute_allocation(const CELTMode *m, int start, int end, const int *offsets, const int *cap, int alloc_trim, int *intensity, int *dual_stereo,
Chris@69:       opus_int32 total, opus_int32 *balance, int *pulses, int *ebits, int *fine_priority, int C, int LM, ec_ctx *ec, int encode, int prev, int signalBandwidth)
Chris@69: {
Chris@69:    int lo, hi, len, j;
Chris@69:    int codedBands;
Chris@69:    int skip_start;
Chris@69:    int skip_rsv;
Chris@69:    int intensity_rsv;
Chris@69:    int dual_stereo_rsv;
Chris@69:    VARDECL(int, bits1);
Chris@69:    VARDECL(int, bits2);
Chris@69:    VARDECL(int, thresh);
Chris@69:    VARDECL(int, trim_offset);
Chris@69:    SAVE_STACK;
Chris@69: 
Chris@69:    total = IMAX(total, 0);
Chris@69:    len = m->nbEBands;
Chris@69:    skip_start = start;
Chris@69:    /* Reserve a bit to signal the end of manually skipped bands. */
Chris@69:    skip_rsv = total >= 1<<BITRES ? 1<<BITRES : 0;
Chris@69:    total -= skip_rsv;
Chris@69:    /* Reserve bits for the intensity and dual stereo parameters. */
Chris@69:    intensity_rsv = dual_stereo_rsv = 0;
Chris@69:    if (C==2)
Chris@69:    {
Chris@69:       intensity_rsv = LOG2_FRAC_TABLE[end-start];
Chris@69:       if (intensity_rsv>total)
Chris@69:          intensity_rsv = 0;
Chris@69:       else
Chris@69:       {
Chris@69:          total -= intensity_rsv;
Chris@69:          dual_stereo_rsv = total>=1<<BITRES ? 1<<BITRES : 0;
Chris@69:          total -= dual_stereo_rsv;
Chris@69:       }
Chris@69:    }
Chris@69:    ALLOC(bits1, len, int);
Chris@69:    ALLOC(bits2, len, int);
Chris@69:    ALLOC(thresh, len, int);
Chris@69:    ALLOC(trim_offset, len, int);
Chris@69: 
Chris@69:    for (j=start;j<end;j++)
Chris@69:    {
Chris@69:       /* Below this threshold, we're sure not to allocate any PVQ bits */
Chris@69:       thresh[j] = IMAX((C)<<BITRES, (3*(m->eBands[j+1]-m->eBands[j])<<LM<<BITRES)>>4);
Chris@69:       /* Tilt of the allocation curve */
Chris@69:       trim_offset[j] = C*(m->eBands[j+1]-m->eBands[j])*(alloc_trim-5-LM)*(end-j-1)
Chris@69:             *(1<<(LM+BITRES))>>6;
Chris@69:       /* Giving less resolution to single-coefficient bands because they get
Chris@69:          more benefit from having one coarse value per coefficient*/
Chris@69:       if ((m->eBands[j+1]-m->eBands[j])<<LM==1)
Chris@69:          trim_offset[j] -= C<<BITRES;
Chris@69:    }
Chris@69:    lo = 1;
Chris@69:    hi = m->nbAllocVectors - 1;
Chris@69:    do
Chris@69:    {
Chris@69:       int done = 0;
Chris@69:       int psum = 0;
Chris@69:       int mid = (lo+hi) >> 1;
Chris@69:       for (j=end;j-->start;)
Chris@69:       {
Chris@69:          int bitsj;
Chris@69:          int N = m->eBands[j+1]-m->eBands[j];
Chris@69:          bitsj = C*N*m->allocVectors[mid*len+j]<<LM>>2;
Chris@69:          if (bitsj > 0)
Chris@69:             bitsj = IMAX(0, bitsj + trim_offset[j]);
Chris@69:          bitsj += offsets[j];
Chris@69:          if (bitsj >= thresh[j] || done)
Chris@69:          {
Chris@69:             done = 1;
Chris@69:             /* Don't allocate more than we can actually use */
Chris@69:             psum += IMIN(bitsj, cap[j]);
Chris@69:          } else {
Chris@69:             if (bitsj >= C<<BITRES)
Chris@69:                psum += C<<BITRES;
Chris@69:          }
Chris@69:       }
Chris@69:       if (psum > total)
Chris@69:          hi = mid - 1;
Chris@69:       else
Chris@69:          lo = mid + 1;
Chris@69:       /*printf ("lo = %d, hi = %d\n", lo, hi);*/
Chris@69:    }
Chris@69:    while (lo <= hi);
Chris@69:    hi = lo--;
Chris@69:    /*printf ("interp between %d and %d\n", lo, hi);*/
Chris@69:    for (j=start;j<end;j++)
Chris@69:    {
Chris@69:       int bits1j, bits2j;
Chris@69:       int N = m->eBands[j+1]-m->eBands[j];
Chris@69:       bits1j = C*N*m->allocVectors[lo*len+j]<<LM>>2;
Chris@69:       bits2j = hi>=m->nbAllocVectors ?
Chris@69:             cap[j] : C*N*m->allocVectors[hi*len+j]<<LM>>2;
Chris@69:       if (bits1j > 0)
Chris@69:          bits1j = IMAX(0, bits1j + trim_offset[j]);
Chris@69:       if (bits2j > 0)
Chris@69:          bits2j = IMAX(0, bits2j + trim_offset[j]);
Chris@69:       if (lo > 0)
Chris@69:          bits1j += offsets[j];
Chris@69:       bits2j += offsets[j];
Chris@69:       if (offsets[j]>0)
Chris@69:          skip_start = j;
Chris@69:       bits2j = IMAX(0,bits2j-bits1j);
Chris@69:       bits1[j] = bits1j;
Chris@69:       bits2[j] = bits2j;
Chris@69:    }
Chris@69:    codedBands = interp_bits2pulses(m, start, end, skip_start, bits1, bits2, thresh, cap,
Chris@69:          total, balance, skip_rsv, intensity, intensity_rsv, dual_stereo, dual_stereo_rsv,
Chris@69:          pulses, ebits, fine_priority, C, LM, ec, encode, prev, signalBandwidth);
Chris@69:    RESTORE_STACK;
Chris@69:    return codedBands;
Chris@69: }
Chris@69: