comparison src/opus-1.3/celt/rate.c @ 154:4664ac0c1032

Add Opus sources and macOS builds

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