Fix misleading comments about ec_{enc|dec}_tell()
[opus.git] / libcelt / bands.c
index ff39149..31d4788 100644 (file)
@@ -1,5 +1,7 @@
-/* (C) 2007-2008 Jean-Marc Valin, CSIRO
-   (C) 2008-2009 Gregory Maxwell */
+/* Copyright (c) 2007-2008 CSIRO
+   Copyright (c) 2007-2009 Xiph.Org Foundation
+   Copyright (c) 2008-2009 Gregory Maxwell 
+   Written by Jean-Marc Valin and Gregory Maxwell */
 /*
    Redistribution and use in source and binary forms, with or without
    modification, are permitted provided that the following conditions
 #include "mathops.h"
 #include "rate.h"
 
-const celt_word16_t sqrtC_1[2] = {QCONST16(1.f, 14), QCONST16(1.414214f, 14)};
 
 #ifdef FIXED_POINT
 /* Compute the amplitude (sqrt energy) in each of the bands */
-void compute_band_energies(const CELTMode *m, const celt_sig_t *X, celt_ener_t *bank)
+void compute_band_energies(const CELTMode *m, const celt_sig *X, celt_ener *bank, int _C, int M)
 {
-   int i, c;
-   const celt_int16_t *eBands = m->eBands;
-   const int C = CHANNELS(m);
+   int i, c, N;
+   const celt_int16 *eBands = m->eBands;
+   const int C = CHANNELS(_C);
+   N = M*m->eBands[m->nbEBands+1];
    for (c=0;c<C;c++)
    {
       for (i=0;i<m->nbEBands;i++)
       {
          int j;
-         celt_word32_t maxval=0;
-         celt_word32_t sum = 0;
+         celt_word32 maxval=0;
+         celt_word32 sum = 0;
          
-         j=eBands[i]; do {
-            maxval = MAX32(maxval, X[j*C+c]);
-            maxval = MAX32(maxval, -X[j*C+c]);
-         } while (++j<eBands[i+1]);
+         j=M*eBands[i]; do {
+            maxval = MAX32(maxval, X[j+c*N]);
+            maxval = MAX32(maxval, -X[j+c*N]);
+         } while (++j<M*eBands[i+1]);
          
          if (maxval > 0)
          {
             int shift = celt_ilog2(maxval)-10;
-            j=eBands[i]; do {
-               sum = MAC16_16(sum, EXTRACT16(VSHR32(X[j*C+c],shift)),
-                                   EXTRACT16(VSHR32(X[j*C+c],shift)));
-            } while (++j<eBands[i+1]);
+            j=M*eBands[i]; do {
+               sum = MAC16_16(sum, EXTRACT16(VSHR32(X[j+c*N],shift)),
+                                   EXTRACT16(VSHR32(X[j+c*N],shift)));
+            } while (++j<M*eBands[i+1]);
             /* We're adding one here to make damn sure we never end up with a pitch vector that's
                larger than unity norm */
-            bank[i*C+c] = EPSILON+VSHR32(EXTEND32(celt_sqrt(sum)),-shift);
+            bank[i+c*m->nbEBands] = EPSILON+VSHR32(EXTEND32(celt_sqrt(sum)),-shift);
          } else {
-            bank[i*C+c] = EPSILON;
+            bank[i+c*m->nbEBands] = EPSILON;
          }
-         /*printf ("%f ", bank[i*C+c]);*/
+         /*printf ("%f ", bank[i+c*m->nbEBands]);*/
       }
    }
    /*printf ("\n");*/
 }
 
 /* Normalise each band such that the energy is one. */
-void normalise_bands(const CELTMode *m, const celt_sig_t * restrict freq, celt_norm_t * restrict X, const celt_ener_t *bank)
+void normalise_bands(const CELTMode *m, const celt_sig * restrict freq, celt_norm * restrict X, const celt_ener *bank, int _C, int M)
 {
-   int i, c;
-   const celt_int16_t *eBands = m->eBands;
-   const int C = CHANNELS(m);
+   int i, c, N;
+   const celt_int16 *eBands = m->eBands;
+   const int C = CHANNELS(_C);
+   N = M*m->eBands[m->nbEBands+1];
    for (c=0;c<C;c++)
    {
       i=0; do {
-         celt_word16_t g;
+         celt_word16 g;
          int j,shift;
-         celt_word16_t E;
-         shift = celt_zlog2(bank[i*C+c])-13;
-         E = VSHR32(bank[i*C+c], shift);
+         celt_word16 E;
+         shift = celt_zlog2(bank[i+c*m->nbEBands])-13;
+         E = VSHR32(bank[i+c*m->nbEBands], shift);
          g = EXTRACT16(celt_rcp(SHL32(E,3)));
-         j=eBands[i]; do {
-            X[j*C+c] = MULT16_16_Q15(VSHR32(freq[j*C+c],shift-1),g);
-         } while (++j<eBands[i+1]);
+         j=M*eBands[i]; do {
+            X[j+c*N] = MULT16_16_Q15(VSHR32(freq[j+c*N],shift-1),g);
+         } while (++j<M*eBands[i+1]);
       } while (++i<m->nbEBands);
    }
 }
 
 #else /* FIXED_POINT */
 /* Compute the amplitude (sqrt energy) in each of the bands */
-void compute_band_energies(const CELTMode *m, const celt_sig_t *X, celt_ener_t *bank)
+void compute_band_energies(const CELTMode *m, const celt_sig *X, celt_ener *bank, int _C, int M)
 {
-   int i, c;
-   const celt_int16_t *eBands = m->eBands;
-   const int C = CHANNELS(m);
+   int i, c, N;
+   const celt_int16 *eBands = m->eBands;
+   const int C = CHANNELS(_C);
+   N = M*m->eBands[m->nbEBands+1];
    for (c=0;c<C;c++)
    {
       for (i=0;i<m->nbEBands;i++)
       {
          int j;
-         celt_word32_t sum = 1e-10;
-         for (j=eBands[i];j<eBands[i+1];j++)
-            sum += X[j*C+c]*X[j*C+c];
-         bank[i*C+c] = sqrt(sum);
-         /*printf ("%f ", bank[i*C+c]);*/
+         celt_word32 sum = 1e-10;
+         for (j=M*eBands[i];j<M*eBands[i+1];j++)
+            sum += X[j+c*N]*X[j+c*N];
+         bank[i+c*m->nbEBands] = sqrt(sum);
+         /*printf ("%f ", bank[i+c*m->nbEBands]);*/
       }
    }
    /*printf ("\n");*/
 }
 
-#ifdef EXP_PSY
-void compute_noise_energies(const CELTMode *m, const celt_sig_t *X, const celt_word16_t *tonality, celt_ener_t *bank)
-{
-   int i, c;
-   const celt_int16_t *eBands = m->eBands;
-   const int C = CHANNELS(m);
-   for (c=0;c<C;c++)
-   {
-      for (i=0;i<m->nbEBands;i++)
-      {
-         int j;
-         celt_word32_t sum = 1e-10;
-         for (j=eBands[i];j<eBands[i+1];j++)
-            sum += X[j*C+c]*X[j*C+c]*tonality[j];
-         bank[i*C+c] = sqrt(sum);
-         /*printf ("%f ", bank[i*C+c]);*/
-      }
-   }
-   /*printf ("\n");*/
-}
-#endif
-
 /* Normalise each band such that the energy is one. */
-void normalise_bands(const CELTMode *m, const celt_sig_t * restrict freq, celt_norm_t * restrict X, const celt_ener_t *bank)
+void normalise_bands(const CELTMode *m, const celt_sig * restrict freq, celt_norm * restrict X, const celt_ener *bank, int _C, int M)
 {
-   int i, c;
-   const celt_int16_t *eBands = m->eBands;
-   const int C = CHANNELS(m);
+   int i, c, N;
+   const celt_int16 *eBands = m->eBands;
+   const int C = CHANNELS(_C);
+   N = M*m->eBands[m->nbEBands+1];
    for (c=0;c<C;c++)
    {
       for (i=0;i<m->nbEBands;i++)
       {
          int j;
-         celt_word16_t g = 1.f/(1e-10+bank[i*C+c]);
-         for (j=eBands[i];j<eBands[i+1];j++)
-            X[j*C+c] = freq[j*C+c]*g;
+         celt_word16 g = 1.f/(1e-10f+bank[i+c*m->nbEBands]);
+         for (j=M*eBands[i];j<M*eBands[i+1];j++)
+            X[j+c*N] = freq[j+c*N]*g;
       }
    }
 }
 
 #endif /* FIXED_POINT */
 
-#ifndef DISABLE_STEREO
-void renormalise_bands(const CELTMode *m, celt_norm_t * restrict X)
+void renormalise_bands(const CELTMode *m, celt_norm * restrict X, int _C, int M)
 {
    int i, c;
-   const celt_int16_t *eBands = m->eBands;
-   const int C = CHANNELS(m);
+   const celt_int16 *eBands = m->eBands;
+   const int C = CHANNELS(_C);
    for (c=0;c<C;c++)
    {
       i=0; do {
-         renormalise_vector(X+C*eBands[i]+c, QCONST16(0.70711f, 15), eBands[i+1]-eBands[i], C);
+         renormalise_vector(X+M*eBands[i]+c*M*eBands[m->nbEBands+1], Q15ONE, M*eBands[i+1]-M*eBands[i], 1);
       } while (++i<m->nbEBands);
    }
 }
-#endif /* DISABLE_STEREO */
 
 /* De-normalise the energy to produce the synthesis from the unit-energy bands */
-void denormalise_bands(const CELTMode *m, const celt_norm_t * restrict X, celt_sig_t * restrict freq, const celt_ener_t *bank)
+void denormalise_bands(const CELTMode *m, const celt_norm * restrict X, celt_sig * restrict freq, const celt_ener *bank, int _C, int M)
 {
-   int i, c;
-   const celt_int16_t *eBands = m->eBands;
-   const int C = CHANNELS(m);
+   int i, c, N;
+   const celt_int16 *eBands = m->eBands;
+   const int C = CHANNELS(_C);
+   N = M*m->eBands[m->nbEBands+1];
    if (C>2)
       celt_fatal("denormalise_bands() not implemented for >2 channels");
    for (c=0;c<C;c++)
    {
+      celt_sig * restrict f;
+      const celt_norm * restrict x;
+      f = freq+c*N;
+      x = X+c*N;
       for (i=0;i<m->nbEBands;i++)
       {
-         int j;
-         celt_word32_t g = SHR32(bank[i*C+c],1);
-         j=eBands[i]; do {
-            freq[j*C+c] = SHL32(MULT16_32_Q15(X[j*C+c], g),2);
-         } while (++j<eBands[i+1]);
+         int j, end;
+         celt_word32 g = SHR32(bank[i+c*m->nbEBands],1);
+         j=M*eBands[i];
+         end = M*eBands[i+1];
+         do {
+            *f++ = SHL32(MULT16_32_Q15(*x, g),2);
+            x++;
+         } while (++j<end);
       }
+      for (i=M*eBands[m->nbEBands];i<M*eBands[m->nbEBands+1];i++)
+         *f++ = 0;
    }
-   for (i=C*eBands[m->nbEBands];i<C*eBands[m->nbEBands+1];i++)
-      freq[i] = 0;
 }
 
-
-/* Compute the best gain for each "pitch band" */
-int compute_pitch_gain(const CELTMode *m, const celt_norm_t *X, const celt_norm_t *P, celt_pgain_t *gains)
+int compute_pitch_gain(const CELTMode *m, const celt_sig *X, const celt_sig *P, int norm_rate, int *gain_id, int _C, celt_word16 *gain_prod, int M)
 {
-   int i;
-   int gain_sum = 0;
-   const celt_int16_t *pBands = m->pBands;
-   const int C = CHANNELS(m);
+   int j, c;
+   celt_word16 g;
+   celt_word16 delta;
+   const int C = CHANNELS(_C);
+   celt_word32 Sxy=0, Sxx=0, Syy=0;
+   int len = M*m->pitchEnd;
+   int N = M*m->eBands[m->nbEBands+1];
+#ifdef FIXED_POINT
+   int shift = 0;
+   celt_word32 maxabs=0;
 
-   for (i=0;i<m->nbPBands;i++)
+   for (c=0;c<C;c++)
    {
-      celt_word32_t Sxy=0, Sxx=0;
-      int j;
-      /* We know we're not going to overflow because Sxx can't be more than 1 (Q28) */
-      for (j=C*pBands[i];j<C*pBands[i+1];j++)
+      for (j=0;j<len;j++)
       {
-         Sxy = MAC16_16(Sxy, X[j], P[j]);
-         Sxx = MAC16_16(Sxx, X[j], X[j]);
+         maxabs = MAX32(maxabs, ABS32(X[j+c*N]));
+         maxabs = MAX32(maxabs, ABS32(P[j+c*N]));
       }
-      /* No negative gain allowed */
-      if (Sxy < 0)
-         Sxy = 0;
-      /* Not sure how that would happen, just making sure */
-      if (Sxy > Sxx)
-         Sxy = Sxx;
-      /* We need to be a bit conservative (multiply gain by 0.9), otherwise the
-         residual doesn't quantise well */
-      Sxy = MULT16_32_Q15(QCONST16(.99f, 15), Sxy);
-      /* gain = Sxy/Sxx */
-      gains[i] = EXTRACT16(celt_div(Sxy,ADD32(SHR32(Sxx, PGAIN_SHIFT),EPSILON)));
-      if (gains[i]>QCONST16(.5,15))
-         gain_sum++;
-      /*printf ("%f ", 1-sqrt(1-gain*gain));*/
    }
-   /*if(rand()%10==0)
+   shift = celt_ilog2(maxabs)-12;
+   if (shift<0)
+      shift = 0;
+#endif
+   delta = PDIV32_16(Q15ONE, len);
+   for (c=0;c<C;c++)
    {
-      for (i=0;i<m->nbPBands;i++)
-         printf ("%f ", 1-sqrt(1-gains[i]*gains[i]));
-      printf ("\n");
-   }*/
-   return gain_sum > 5;
-}
+      celt_word16 gg = Q15ONE;
+      for (j=0;j<len;j++)
+      {
+         celt_word16 Xj, Pj;
+         Xj = EXTRACT16(SHR32(X[j+c*N], shift));
+         Pj = MULT16_16_P15(gg,EXTRACT16(SHR32(P[j+c*N], shift)));
+         Sxy = MAC16_16(Sxy, Xj, Pj);
+         Sxx = MAC16_16(Sxx, Pj, Pj);
+         Syy = MAC16_16(Syy, Xj, Xj);
+         gg = SUB16(gg, delta);
+      }
+   }
+#ifdef FIXED_POINT
+   {
+      celt_word32 num, den;
+      celt_word16 fact;
+      fact = MULT16_16(QCONST16(.04f, 14), norm_rate);
+      if (fact < QCONST16(1.f, 14))
+         fact = QCONST16(1.f, 14);
+      num = Sxy;
+      den = EPSILON+Sxx+MULT16_32_Q15(QCONST16(.03f,15),Syy);
+      shift = celt_zlog2(Sxy)-16;
+      if (shift < 0)
+         shift = 0;
+      if (Sxy < MULT16_32_Q15(fact, MULT16_16(celt_sqrt(EPSILON+Sxx),celt_sqrt(EPSILON+Syy))))
+         g = 0;
+      else
+         g = DIV32(SHL32(SHR32(num,shift),14),ADD32(EPSILON,SHR32(den,shift)));
 
-static void intensity_band(celt_norm_t * restrict X, int len)
-{
-   int j;
-   celt_word32_t E = 1e-15;
-   celt_word32_t E2 = 1e-15;
-   for (j=0;j<len;j++)
+      /* This MUST round down so that we don't over-estimate the gain */
+      *gain_id = EXTRACT16(SHR32(MULT16_16(20,(g-QCONST16(.5f,14))),14));
+   }
+#else
    {
-      X[j] = X[2*j];
-      E = MAC16_16(E, X[j],X[j]);
-      E2 = MAC16_16(E2, X[2*j+1],X[2*j+1]);
+      float fact = .04f*norm_rate;
+      if (fact < 1)
+         fact = 1;
+      g = Sxy/(.1f+Sxx+.03f*Syy);
+      if (Sxy < .5f*fact*celt_sqrt(1+Sxx*Syy))
+         g = 0;
+      /* This MUST round down so that we don't over-estimate the gain */
+      *gain_id = floor(20*(g-.5f));
    }
-#ifndef FIXED_POINT
-   E  = celt_sqrt(E+E2)/celt_sqrt(E);
-   for (j=0;j<len;j++)
-      X[j] *= E;
 #endif
-   for (j=0;j<len;j++)
-      X[len+j] = 0;
-
-}
+   /* This prevents the pitch gain from being above 1.0 for too long by bounding the 
+      maximum error amplification factor to 2.0 */
+   g = ADD16(QCONST16(.5f,14), MULT16_16_16(QCONST16(.05f,14),*gain_id));
+   *gain_prod = MAX16(QCONST32(1.f, 13), MULT16_16_Q14(*gain_prod,g));
+   if (*gain_prod>QCONST32(2.f, 13))
+   {
+      *gain_id=9;
+      *gain_prod = QCONST32(2.f, 13);
+   }
 
-static void dup_band(celt_norm_t * restrict X, int len)
-{
-   int j;
-   for (j=len-1;j>=0;j--)
+   if (*gain_id < 0)
    {
-      X[2*j] = MULT16_16_Q15(QCONST16(.70711f,15),X[j]);
-      X[2*j+1] = MULT16_16_Q15(QCONST16(.70711f,15),X[j]);
+      *gain_id = 0;
+      return 0;
+   } else {
+      if (*gain_id > 15)
+         *gain_id = 15;
+      return 1;
    }
 }
 
-static void stereo_band_mix(const CELTMode *m, celt_norm_t *X, const celt_ener_t *bank, int stereo_mode, int bandID, int dir)
+void apply_pitch(const CELTMode *m, celt_sig *X, const celt_sig *P, int gain_id, int pred, int _C, int M)
 {
-   int i = bandID;
-   const celt_int16_t *eBands = m->eBands;
-   const int C = CHANNELS(m);
+   int j, c, N;
+   celt_word16 gain;
+   celt_word16 delta;
+   const int C = CHANNELS(_C);
+   int len = M*m->pitchEnd;
+
+   N = M*m->eBands[m->nbEBands+1];
+   gain = ADD16(QCONST16(.5f,14), MULT16_16_16(QCONST16(.05f,14),gain_id));
+   delta = PDIV32_16(gain, len);
+   if (pred)
+      gain = -gain;
+   else
+      delta = -delta;
+   for (c=0;c<C;c++)
    {
-      int j;
-      if (stereo_mode && dir <0)
-      {
-         dup_band(X+C*eBands[i], eBands[i+1]-eBands[i]);
-      } else {
-         celt_word16_t a1, a2;
-         if (stereo_mode==0)
-         {
-            /* Do mid-side when not doing intensity stereo */
-            a1 = QCONST16(.70711f,14);
-            a2 = dir*QCONST16(.70711f,14);
-         } else {
-            celt_word16_t left, right;
-            celt_word16_t norm;
-#ifdef FIXED_POINT
-            int shift = celt_zlog2(MAX32(bank[i*C], bank[i*C+1]))-13;
-#endif
-            left = VSHR32(bank[i*C],shift);
-            right = VSHR32(bank[i*C+1],shift);
-            norm = EPSILON + celt_sqrt(EPSILON+MULT16_16(left,left)+MULT16_16(right,right));
-            a1 = DIV32_16(SHL32(EXTEND32(left),14),norm);
-            a2 = dir*DIV32_16(SHL32(EXTEND32(right),14),norm);
-         }
-         for (j=eBands[i];j<eBands[i+1];j++)
-         {
-            celt_norm_t r, l;
-            l = X[j*C];
-            r = X[j*C+1];
-            X[j*C] = MULT16_16_Q14(a1,l) + MULT16_16_Q14(a2,r);
-            X[j*C+1] = MULT16_16_Q14(a1,r) - MULT16_16_Q14(a2,l);
-         }
-      }
-      if (stereo_mode && dir>0)
+      celt_word16 gg = gain;
+      for (j=0;j<len;j++)
       {
-         intensity_band(X+C*eBands[i], eBands[i+1]-eBands[i]);
+         X[j+c*N] += SHL32(MULT16_32_Q15(gg,P[j+c*N]),1);
+         gg = ADD16(gg, delta);
       }
    }
 }
 
-static void point_stereo_mix(const CELTMode *m, celt_norm_t *X, const celt_ener_t *bank, int bandID, int dir)
+static void stereo_band_mix(const CELTMode *m, celt_norm *X, celt_norm *Y, const celt_ener *bank, int stereo_mode, int bandID, int dir, int N)
 {
    int i = bandID;
-   const celt_int16_t *eBands = m->eBands;
-   const int C = CHANNELS(m);
-   celt_word16_t left, right;
-   celt_word16_t norm;
-   celt_word16_t a1, a2;
    int j;
+   celt_word16 a1, a2;
+   if (stereo_mode==0)
+   {
+      /* Do mid-side when not doing intensity stereo */
+      a1 = QCONST16(.70711f,14);
+      a2 = dir*QCONST16(.70711f,14);
+   } else {
+      celt_word16 left, right;
+      celt_word16 norm;
 #ifdef FIXED_POINT
-   int shift = celt_zlog2(MAX32(bank[i*C], bank[i*C+1]))-13;
+      int shift = celt_zlog2(MAX32(bank[i], bank[i+m->nbEBands]))-13;
 #endif
-   left = VSHR32(bank[i*C],shift);
-   right = VSHR32(bank[i*C+1],shift);
-   norm = EPSILON + celt_sqrt(EPSILON+MULT16_16(left,left)+MULT16_16(right,right));
-   a1 = DIV32_16(SHL32(EXTEND32(left),14),norm);
-   a2 = dir*DIV32_16(SHL32(EXTEND32(right),14),norm);
-   for (j=eBands[i];j<eBands[i+1];j++)
+      left = VSHR32(bank[i],shift);
+      right = VSHR32(bank[i+m->nbEBands],shift);
+      norm = EPSILON + celt_sqrt(EPSILON+MULT16_16(left,left)+MULT16_16(right,right));
+      a1 = DIV32_16(SHL32(EXTEND32(left),14),norm);
+      a2 = dir*DIV32_16(SHL32(EXTEND32(right),14),norm);
+   }
+   for (j=0;j<N;j++)
    {
-      celt_norm_t r, l;
-      l = X[j*C];
-      r = X[j*C+1];
-      X[j*C] = MULT16_16_Q14(a1,l) + MULT16_16_Q14(a2,r);
-      X[j*C+1] = MULT16_16_Q14(a1,r) - MULT16_16_Q14(a2,l);
+      celt_norm r, l;
+      l = X[j];
+      r = Y[j];
+      X[j] = MULT16_16_Q14(a1,l) + MULT16_16_Q14(a2,r);
+      Y[j] = MULT16_16_Q14(a1,r) - MULT16_16_Q14(a2,l);
    }
 }
 
-void stereo_decision(const CELTMode *m, celt_norm_t * restrict X, int *stereo_mode, int len)
-{
-   int i;
-   for (i=0;i<len-5;i++)
-      stereo_mode[i] = 0;
-   for (;i<len;i++)
-      stereo_mode[i] = 0;
-}
 
-void interleave(celt_norm_t *x, int N)
+int folding_decision(const CELTMode *m, celt_norm *X, celt_word16 *average, int *last_decision, int _C, int M)
 {
-   int i;
-   VARDECL(celt_norm_t, tmp);
-   SAVE_STACK;
-   ALLOC(tmp, N, celt_norm_t);
+   int i, c, N0;
+   int NR=0;
+   celt_word32 ratio = EPSILON;
+   const int C = CHANNELS(_C);
+   const celt_int16 * restrict eBands = m->eBands;
    
-   for (i=0;i<N;i++)
-      tmp[i] = x[i];
-   for (i=0;i<N>>1;i++)
+   N0 = M*m->eBands[m->nbEBands+1];
+
+   for (c=0;c<C;c++)
+   {
+   for (i=0;i<m->nbEBands;i++)
+   {
+      int j, N;
+      int max_i=0;
+      celt_word16 max_val=EPSILON;
+      celt_word32 floor_ener=EPSILON;
+      celt_norm * restrict x = X+M*eBands[i]+c*N0;
+      N = M*eBands[i+1]-M*eBands[i];
+      for (j=0;j<N;j++)
+      {
+         if (ABS16(x[j])>max_val)
+         {
+            max_val = ABS16(x[j]);
+            max_i = j;
+         }
+      }
+#if 0
+      for (j=0;j<N;j++)
+      {
+         if (abs(j-max_i)>2)
+            floor_ener += x[j]*x[j];
+      }
+#else
+      floor_ener = QCONST32(1.,28)-MULT16_16(max_val,max_val);
+      if (max_i < N-1)
+         floor_ener -= MULT16_16(x[(max_i+1)], x[(max_i+1)]);
+      if (max_i < N-2)
+         floor_ener -= MULT16_16(x[(max_i+2)], x[(max_i+2)]);
+      if (max_i > 0)
+         floor_ener -= MULT16_16(x[(max_i-1)], x[(max_i-1)]);
+      if (max_i > 1)
+         floor_ener -= MULT16_16(x[(max_i-2)], x[(max_i-2)]);
+      floor_ener = MAX32(floor_ener, EPSILON);
+#endif
+      if (N>7)
+      {
+         celt_word16 r;
+         celt_word16 den = celt_sqrt(floor_ener);
+         den = MAX32(QCONST16(.02f, 15), den);
+         r = DIV32_16(SHL32(EXTEND32(max_val),8),den);
+         ratio = ADD32(ratio, EXTEND32(r));
+         NR++;
+      }
+   }
+   }
+   if (NR>0)
+      ratio = DIV32_16(ratio, NR);
+   ratio = ADD32(HALF32(ratio), HALF32(*average));
+   if (!*last_decision)
    {
-      x[i<<1] = tmp[i];
-      x[(i<<1)+1] = tmp[i+(N>>1)];
+      *last_decision = (ratio < QCONST16(1.8f,8));
+   } else {
+      *last_decision = (ratio < QCONST16(3.f,8));
    }
-   RESTORE_STACK;
+   *average = EXTRACT16(ratio);
+   return *last_decision;
 }
 
-void deinterleave(celt_norm_t *x, int N)
+static void interleave_vector(celt_norm *X, int N0, int stride)
 {
-   int i;
-   VARDECL(celt_norm_t, tmp);
+   int i,j;
+   VARDECL(celt_norm, tmp);
+   int N;
    SAVE_STACK;
-   ALLOC(tmp, N, celt_norm_t);
-   
-   for (i=0;i<N;i++)
-      tmp[i] = x[i];
-   for (i=0;i<N>>1;i++)
-   {
-      x[i] = tmp[i<<1];
-      x[i+(N>>1)] = tmp[(i<<1)+1];
-   }
+   N = N0*stride;
+   ALLOC(tmp, N, celt_norm);
+   for (i=0;i<stride;i++)
+      for (j=0;j<N0;j++)
+         tmp[j*stride+i] = X[i*N0+j];
+   for (j=0;j<N;j++)
+      X[j] = tmp[j];
    RESTORE_STACK;
 }
 
-/* Quantisation of the residual */
-void quant_bands(const CELTMode *m, celt_norm_t * restrict X, celt_norm_t *P, celt_mask_t *W, int pitch_used, celt_pgain_t *pgains, const celt_ener_t *bandE, int *pulses, int shortBlocks, int fold, int total_bits, ec_enc *enc)
+static void deinterleave_vector(celt_norm *X, int N0, int stride)
 {
-   int i, j, remaining_bits, balance;
-   const celt_int16_t * restrict eBands = m->eBands;
-   celt_norm_t * restrict norm;
-   VARDECL(celt_norm_t, _norm);   const celt_int16_t *pBands = m->pBands;
-   int pband=-1;
-   int B;
+   int i,j;
+   VARDECL(celt_norm, tmp);
+   int N;
    SAVE_STACK;
+   N = N0*stride;
+   ALLOC(tmp, N, celt_norm);
+   for (i=0;i<stride;i++)
+      for (j=0;j<N0;j++)
+         tmp[i*N0+j] = X[j*stride+i];
+   for (j=0;j<N;j++)
+      X[j] = tmp[j];
+   RESTORE_STACK;
+}
 
-   B = shortBlocks ? m->nbShortMdcts : 1;
-   ALLOC(_norm, eBands[m->nbEBands+1], celt_norm_t);
-   norm = _norm;
-
-   balance = 0;
-   /*printf("bits left: %d\n", bits);
-   for (i=0;i<m->nbEBands;i++)
-      printf ("(%d %d) ", pulses[i], ebits[i]);
-   printf ("\n");*/
-   /*printf ("%d %d\n", ec_enc_tell(enc, 0), compute_allocation(m, m->nbPulses));*/
-   for (i=0;i<m->nbEBands;i++)
-   {
-      int tell;
-      int q;
-      celt_word16_t n;
-      const celt_int16_t * const *BPbits;
-      
-      int curr_balance, curr_bits;
-      
-      BPbits = m->bits;
-
-      tell = ec_enc_tell(enc, 4);
-      if (i != 0)
-         balance -= tell;
-      remaining_bits = (total_bits<<BITRES)-tell-1;
-      curr_balance = (m->nbEBands-i);
-      if (curr_balance > 3)
-         curr_balance = 3;
-      curr_balance = balance / curr_balance;
-      q = bits2pulses(m, BPbits[i], pulses[i]+curr_balance);
-      curr_bits = BPbits[i][q];
-      remaining_bits -= curr_bits;
-      while (remaining_bits < 0 && q > 0)
+static void haar1(celt_norm *X, int N0, int stride)
+{
+   int i, j;
+   N0 >>= 1;
+   for (i=0;i<stride;i++)
+      for (j=0;j<N0;j++)
       {
-         remaining_bits += curr_bits;
-         q--;
-         curr_bits = BPbits[i][q];
-         remaining_bits -= curr_bits;
+         celt_norm tmp = X[stride*2*j+i];
+         X[stride*2*j+i] = MULT16_16_Q15(QCONST16(.7070678f,15), X[stride*2*j+i] + X[stride*(2*j+1)+i]);
+         X[stride*(2*j+1)+i] = MULT16_16_Q15(QCONST16(.7070678f,15), tmp - X[stride*(2*j+1)+i]);
       }
-      balance += pulses[i] + tell;
-      
-      n = SHL16(celt_sqrt(eBands[i+1]-eBands[i]),11);
+}
 
-      /* If pitch is in use and this eBand begins a pitch band, encode the pitch gain flag */
-      if (pitch_used && eBands[i]< m->pitchEnd && eBands[i] == pBands[pband+1])
+/* This function is responsible for encoding and decoding a band for both
+   the mono and stereo case. Even in the mono case, it can split the band
+   in two and transmit the energy difference with the two half-bands. It
+   can be called recursively so bands can end up being split in 8 parts. */
+static void quant_band(int encode, const CELTMode *m, int i, celt_norm *X, celt_norm *Y,
+      int N, int b, int spread, int tf_change, celt_norm *lowband, int resynth, void *ec,
+      celt_int32 *remaining_bits, int LM, celt_norm *lowband_out, const celt_ener *bandE, int level)
+{
+   int q;
+   int curr_bits;
+   int stereo, split;
+   int imid=0, iside=0;
+   int N0=N;
+   int N_B=N;
+   int N_B0;
+   int spread0=spread;
+   int time_divide=0;
+   int recombine=0;
+
+   if (spread)
+      N_B /= spread;
+   N_B0 = N_B;
+
+   split = stereo = Y != NULL;
+
+   /* Special case for one sample */
+   if (N==1)
+   {
+      int c;
+      celt_norm *x = X;
+      for (c=0;c<1+stereo;c++)
       {
-         int enabled = 1;
-         pband++;
-         if (remaining_bits >= 1<<BITRES) {
-           enabled = pgains[pband] > QCONST16(.5,15);
-           ec_enc_bits(enc, enabled, 1);
-           balance += 1<<BITRES;
+         int sign=0;
+         if (b>=1<<BITRES && *remaining_bits>=1<<BITRES)
+         {
+            if (encode)
+            {
+               sign = x[0]<0;
+               ec_enc_bits((ec_enc*)ec, sign, 1);
+            } else {
+               sign = ec_dec_bits((ec_dec*)ec, 1);
+            }
+            *remaining_bits -= 1<<BITRES;
+            b-=1<<BITRES;
          }
-         if (enabled)
-            pgains[pband] = QCONST16(.9,15);
-         else
-            pgains[pband] = 0;
+         if (resynth)
+            x[0] = sign ? -NORM_SCALING : NORM_SCALING;
+         x = Y;
       }
+      if (lowband_out)
+         lowband_out[0] = X[0];
+      return;
+   }
 
-      /* If pitch isn't available, use intra-frame prediction */
-      if ((eBands[i] >= m->pitchEnd && fold) || q<=0)
+   /* Band recombining to increase frequency resolution */
+   if (!stereo && spread > 1 && level == 0 && tf_change>0)
+   {
+      while (spread>1 && tf_change>0)
       {
-         intra_fold(m, X+eBands[i], eBands[i+1]-eBands[i], q, norm, P+eBands[i], eBands[i], B);
-      } else if (pitch_used && eBands[i] < m->pitchEnd) {
-         for (j=eBands[i];j<eBands[i+1];j++)
-            P[j] = MULT16_16_Q15(pgains[pband], P[j]);
-      } else {
-         for (j=eBands[i];j<eBands[i+1];j++)
-            P[j] = 0;
+         spread>>=1;
+         N_B<<=1;
+         if (encode)
+            haar1(X, N_B, spread);
+         if (lowband)
+            haar1(lowband, N_B, spread);
+         recombine++;
+         tf_change--;
       }
-      
-      if (q > 0)
+      spread0=spread;
+      N_B0 = N_B;
+   }
+
+   /* Increasing the time resolution */
+   if (!stereo && level==0)
+   {
+      while ((N_B&1) == 0 && tf_change<0 && spread <= (1<<LM))
       {
-         alg_quant(X+eBands[i], W+eBands[i], eBands[i+1]-eBands[i], q, P+eBands[i], enc);
-      } else {
-         for (j=eBands[i];j<eBands[i+1];j++)
-            X[j] = P[j];
+         if (encode)
+            haar1(X, N_B, spread);
+         if (lowband)
+            haar1(lowband, N_B, spread);
+         spread <<= 1;
+         N_B >>= 1;
+         time_divide++;
+         tf_change++;
       }
-      for (j=eBands[i];j<eBands[i+1];j++)
-         norm[j] = MULT16_16_Q15(n,X[j]);
+      spread0 = spread;
+      N_B0 = N_B;
    }
-   RESTORE_STACK;
-}
 
-void quant_bands_stereo(const CELTMode *m, celt_norm_t * restrict X, celt_norm_t *P, celt_mask_t *W, int pitch_used, celt_pgain_t *pgains, const celt_ener_t *bandE, int *pulses, int shortBlocks, int fold, int total_bits, ec_enc *enc)
-{
-   int i, j, remaining_bits, balance;
-   const celt_int16_t * restrict eBands = m->eBands;
-   celt_norm_t * restrict norm;
-   VARDECL(celt_norm_t, _norm);
-   const int C = CHANNELS(m);
-   const celt_int16_t *pBands = m->pBands;
-   int pband=-1;
-   int B;
-   celt_word16_t mid, side;
-   SAVE_STACK;
+   /* Reorganize the samples in time order instead of frequency order */
+   if (!stereo && spread0>1 && level==0)
+   {
+      if (encode)
+         deinterleave_vector(X, N_B, spread0);
+      if (lowband)
+         deinterleave_vector(lowband, N_B, spread0);
+   }
 
-   B = shortBlocks ? m->nbShortMdcts : 1;
-   ALLOC(_norm, C*eBands[m->nbEBands+1], celt_norm_t);
-   norm = _norm;
+   /* If we need more than 32 bits, try splitting the band in two. */
+   if (!stereo && LM != -1 && b > 32<<BITRES && N>2)
+   {
+      if (LM>0 || (N&1)==0)
+      {
+         N >>= 1;
+         Y = X+N;
+         split = 1;
+         LM -= 1;
+         spread = (spread+1)>>1;
+      }
+   }
 
-   balance = 0;
-   /*printf("bits left: %d\n", bits);
-   for (i=0;i<m->nbEBands;i++)
-   printf ("(%d %d) ", pulses[i], ebits[i]);
-   printf ("\n");*/
-   /*printf ("%d %d\n", ec_enc_tell(enc, 0), compute_allocation(m, m->nbPulses));*/
-   for (i=0;i<m->nbEBands;i++)
+   if (split)
    {
-      int tell;
-      int q1, q2;
-      celt_word16_t n;
-      const celt_int16_t * const *BPbits;
-      int b, qb;
-      int N;
-      int curr_balance, curr_bits;
-      int imid, iside, itheta;
+      int qb;
+      int itheta=0;
       int mbits, sbits, delta;
       int qalloc;
-      
-      BPbits = m->bits;
+      celt_word16 mid, side;
+      int offset, N2;
+      offset = m->logN[i]+(LM<<BITRES)-QTHETA_OFFSET;
+
+      /* Decide on the resolution to give to the split parameter theta */
+      N2 = 2*N-1;
+      if (stereo && N>2)
+         N2--;
+      qb = (b+N2*offset)/(N2<<BITRES);
+      if (qb > (b>>(BITRES+1))-1)
+         qb = (b>>(BITRES+1))-1;
 
-      N = eBands[i+1]-eBands[i];
-      tell = ec_enc_tell(enc, 4);
-      if (i != 0)
-         balance -= tell;
-      remaining_bits = (total_bits<<BITRES)-tell-1;
-      curr_balance = (m->nbEBands-i);
-      if (curr_balance > 3)
-         curr_balance = 3;
-      curr_balance = balance / curr_balance;
-      b = IMIN(remaining_bits+1,pulses[i]+curr_balance);
-      if (b<0)
-         b = 0;
+      if (qb<0)
+         qb = 0;
+      if (qb>14)
+         qb = 14;
 
-      if (N<5) {
-         
-         q1 = bits2pulses(m, BPbits[i], b/2);
-         curr_bits = 2*BPbits[i][q1];
-         remaining_bits -= curr_bits;
-         while (remaining_bits < 0 && q1 > 0)
-         {
-            remaining_bits += curr_bits;
-            q1--;
-            curr_bits = 2*BPbits[i][q1];
-            remaining_bits -= curr_bits;
-         }
-         balance += pulses[i] + tell;
-         
-         n = SHL16(celt_sqrt((eBands[i+1]-eBands[i])),11);
-         
-         /* If pitch is in use and this eBand begins a pitch band, encode the pitch gain flag */
-         if (pitch_used && eBands[i]< m->pitchEnd && eBands[i] == pBands[pband+1])
-         {
-            int enabled = 1;
-            pband++;
-            if (remaining_bits >= 1<<BITRES) {
-               enabled = pgains[pband] > QCONST16(.5,15);
-               ec_enc_bits(enc, enabled, 1);
-               balance += 1<<BITRES;
-            }
-            if (enabled)
-               pgains[pband] = QCONST16(.9,15);
-            else
-               pgains[pband] = 0;
-         }
+      qalloc = 0;
+      if (qb!=0)
+      {
+         int shift;
+         shift = 14-qb;
 
-         /* If pitch isn't available, use intra-frame prediction */
-         if ((eBands[i] >= m->pitchEnd && fold) || q1<=0)
+         if (encode)
          {
-            intra_fold(m, X+C*eBands[i], eBands[i+1]-eBands[i], q1, norm, P+C*eBands[i], eBands[i], B);
-            deinterleave(P+C*eBands[i], C*N);
-         } else if (pitch_used && eBands[i] < m->pitchEnd) {
-            deinterleave(P+C*eBands[i], C*N);
-            for (j=C*eBands[i];j<C*eBands[i+1];j++)
-               P[j] = MULT16_16_Q15(pgains[pband], P[j]);
-         } else {
-            for (j=C*eBands[i];j<C*eBands[i+1];j++)
-               P[j] = 0;
+            if (stereo)
+               stereo_band_mix(m, X, Y, bandE, qb==0, i, 1, N);
+
+            mid = renormalise_vector(X, Q15ONE, N, 1);
+            side = renormalise_vector(Y, Q15ONE, N, 1);
+
+            /* theta is the atan() of the ration between the (normalized)
+               side and mid. With just that parameter, we can re-scale both
+               mid and side because we know that 1) they have unit norm and
+               2) they are orthogonal. */
+   #ifdef FIXED_POINT
+            /* 0.63662 = 2/pi */
+            itheta = MULT16_16_Q15(QCONST16(0.63662f,15),celt_atan2p(side, mid));
+   #else
+            itheta = floor(.5f+16384*0.63662f*atan2(side,mid));
+   #endif
+
+            itheta = (itheta+(1<<shift>>1))>>shift;
          }
-         deinterleave(X+C*eBands[i], C*N);
-         if (q1 > 0)
+
+         /* Entropy coding of the angle. We use a uniform pdf for the
+            first stereo split but a triangular one for the rest. */
+         if (stereo || qb>9 || spread>1)
          {
-            alg_quant(X+C*eBands[i], W+C*eBands[i], N, q1, P+C*eBands[i], enc);
-            alg_quant(X+C*eBands[i]+N, W+C*eBands[i], N, q1, P+C*eBands[i]+N, enc);
+            if (encode)
+               ec_enc_uint((ec_enc*)ec, itheta, (1<<qb)+1);
+            else
+               itheta = ec_dec_uint((ec_dec*)ec, (1<<qb)+1);
+            qalloc = log2_frac((1<<qb)+1,BITRES);
          } else {
-            for (j=C*eBands[i];j<C*eBands[i+1];j++)
-               X[j] = P[j];
+            int fs=1, ft;
+            ft = ((1<<qb>>1)+1)*((1<<qb>>1)+1);
+            if (encode)
+            {
+               int j;
+               int fl=0;
+               j=0;
+               while(1)
+               {
+                  if (j==itheta)
+                     break;
+                  fl+=fs;
+                  if (j<(1<<qb>>1))
+                     fs++;
+                  else
+                     fs--;
+                  j++;
+               }
+               ec_encode((ec_enc*)ec, fl, fl+fs, ft);
+            } else {
+               int fl=0;
+               int j, fm;
+               fm = ec_decode((ec_dec*)ec, ft);
+               j=0;
+               while (1)
+               {
+                  if (fm < fl+fs)
+                     break;
+                  fl+=fs;
+                  if (j<(1<<qb>>1))
+                     fs++;
+                  else
+                     fs--;
+                  j++;
+               }
+               itheta = j;
+               ec_dec_update((ec_dec*)ec, fl, fl+fs, ft);
+            }
+            qalloc = log2_frac(ft,BITRES) - log2_frac(fs,BITRES) + 1;
          }
-
-         interleave(X+C*eBands[i], C*N);
-         for (j=0;j<C*N;j++)
-            norm[eBands[i]+j] = MULT16_16_Q15(n,X[C*eBands[i]+j]);
-
-      } else {
-      qb = (b-2*(N-1)*(40-log2_frac(N,4)))/(32*(N-1));
-      if (qb > (b>>BITRES)-1)
-         qb = (b>>BITRES)-1;
-      if (qb<0)
-         qb = 0;
-      
-      if (qb==0)
-         point_stereo_mix(m, X, bandE, i, 1);
-      else
-         stereo_band_mix(m, X, bandE, 0, i, 1);
-      
-      mid = renormalise_vector(X+C*eBands[i], Q15ONE, N, C);
-      side = renormalise_vector(X+C*eBands[i]+1, Q15ONE, N, C);
-#ifdef FIXED_POINT
-      itheta = MULT16_16_Q15(QCONST16(0.63662,15),celt_atan2p(side, mid));
-#else
-      itheta = floor(.5+16384*0.63662*atan2(side,mid));
-#endif
-      qalloc = log2_frac((1<<qb)+1,4);
-      if (qb==0)
-      {
-         itheta=0;
-      } else {
-         int shift;
-         shift = 14-qb;
-         itheta = (itheta+(1<<shift>>1))>>shift;
-         ec_enc_uint(enc, itheta, (1<<qb)+1);
          itheta <<= shift;
       }
+
       if (itheta == 0)
       {
          imid = 32767;
@@ -645,247 +693,240 @@ void quant_bands_stereo(const CELTMode *m, celt_norm_t * restrict X, celt_norm_t
       } else {
          imid = bitexact_cos(itheta);
          iside = bitexact_cos(16384-itheta);
-         delta = (N-1)*(log2_frac(iside,6)-log2_frac(imid,6))>>2;
+         /* This is the mid vs side allocation that minimizes squared error
+            in that band. */
+         delta = (N-1)*(log2_frac(iside,BITRES+2)-log2_frac(imid,BITRES+2))>>2;
       }
-      mbits = (b-qalloc/2-delta)/2;
-      if (mbits > b-qalloc)
-         mbits = b-qalloc;
-      if (mbits<0)
-         mbits=0;
-      sbits = b-qalloc-mbits;
-      q1 = bits2pulses(m, BPbits[i], mbits);
-      q2 = bits2pulses(m, BPbits[i], sbits);
-      curr_bits = BPbits[i][q1]+BPbits[i][q2]+qalloc;
-      remaining_bits -= curr_bits;
-      while (remaining_bits < 0 && (q1 > 0 || q2 > 0))
+
+      /* This is a special case for N=2 that only works for stereo and takes
+         advantage of the fact that mid and side are orthogonal to encode
+         the side with just one bit. */
+      if (N==2 && stereo)
       {
-         remaining_bits += curr_bits;
-         if (q1>q2)
+         int c, c2;
+         int sign=1;
+         celt_norm v[2], w[2];
+         celt_norm *x2, *y2;
+         mbits = b-qalloc;
+         sbits = 0;
+         if (itheta != 0 && itheta != 16384)
+            sbits = 1<<BITRES;
+         mbits -= sbits;
+         c = itheta > 8192 ? 1 : 0;
+         *remaining_bits -= qalloc+sbits;
+
+         x2 = X;
+         y2 = Y;
+         if (encode)
          {
-            q1--;
-            curr_bits = BPbits[i][q1]+BPbits[i][q2]+qalloc;
+            c2 = 1-c;
+
+            if (c==0)
+            {
+               v[0] = x2[0];
+               v[1] = x2[1];
+               w[0] = y2[0];
+               w[1] = y2[1];
+            } else {
+               v[0] = y2[0];
+               v[1] = y2[1];
+               w[0] = x2[0];
+               w[1] = x2[1];
+            }
+            /* Here we only need to encode a sign for the side */
+            if (v[0]*w[1] - v[1]*w[0] > 0)
+               sign = 1;
+            else
+               sign = -1;
+         }
+         quant_band(encode, m, i, v, NULL, N, mbits, spread, tf_change, lowband, resynth, ec, remaining_bits, LM, lowband_out, NULL, level+1);
+         if (sbits)
+         {
+            if (encode)
+            {
+               ec_enc_bits((ec_enc*)ec, sign==1, 1);
+            } else {
+               sign = 2*ec_dec_bits((ec_dec*)ec, 1)-1;
+            }
          } else {
-            q2--;
-            curr_bits = BPbits[i][q1]+BPbits[i][q2]+qalloc;
+            sign = 1;
          }
-         remaining_bits -= curr_bits;
-      }
-      balance += pulses[i] + tell;
-      
-      n = SHL16(celt_sqrt((eBands[i+1]-eBands[i])),11);
-
-      /* If pitch is in use and this eBand begins a pitch band, encode the pitch gain flag */
-      if (pitch_used && eBands[i]< m->pitchEnd && eBands[i] == pBands[pband+1])
-      {
-         int enabled = 1;
-         pband++;
-         if (remaining_bits >= 1<<BITRES) {
-            enabled = pgains[pband] > QCONST16(.5,15);
-            ec_enc_bits(enc, enabled, 1);
-            balance += 1<<BITRES;
+         w[0] = -sign*v[1];
+         w[1] = sign*v[0];
+         if (c==0)
+         {
+            x2[0] = v[0];
+            x2[1] = v[1];
+            y2[0] = w[0];
+            y2[1] = w[1];
+         } else {
+            x2[0] = w[0];
+            x2[1] = w[1];
+            y2[0] = v[0];
+            y2[1] = v[1];
          }
-         if (enabled)
-            pgains[pband] = QCONST16(.9,15);
+      } else
+      {
+         /* "Normal" split code */
+         celt_norm *next_lowband2=NULL;
+         celt_norm *next_lowband_out1=NULL;
+         int next_level=0;
+
+         /* Give more bits to low-energy MDCTs than they would otherwise deserve */
+         if (spread>1 && !stereo)
+            delta >>= 1;
+
+         mbits = (b-qalloc/2-delta)/2;
+         if (mbits > b-qalloc)
+            mbits = b-qalloc;
+         if (mbits<0)
+            mbits=0;
+         sbits = b-qalloc-mbits;
+         *remaining_bits -= qalloc;
+
+         if (lowband && !stereo)
+            next_lowband2 = lowband+N;
+         if (stereo)
+            next_lowband_out1 = lowband_out;
          else
-            pgains[pband] = 0;
+            next_level = level+1;
+
+         quant_band(encode, m, i, X, NULL, N, mbits, spread, tf_change, lowband, resynth, ec, remaining_bits, LM, next_lowband_out1, NULL, next_level);
+         quant_band(encode, m, i, Y, NULL, N, sbits, spread, tf_change, next_lowband2, resynth, ec, remaining_bits, LM, NULL, NULL, level);
       }
-      
 
-      /* If pitch isn't available, use intra-frame prediction */
-      if ((eBands[i] >= m->pitchEnd && fold) || (q1+q2)<=0)
+   } else {
+      /* This is the basic no-split case */
+      q = bits2pulses(m, m->bits[LM][i], N, b);
+      curr_bits = pulses2bits(m->bits[LM][i], N, q);
+      *remaining_bits -= curr_bits;
+
+      /* Ensures we can never bust the budget */
+      while (*remaining_bits < 0 && q > 0)
       {
-         intra_fold(m, X+C*eBands[i], eBands[i+1]-eBands[i], q1+q2, norm, P+C*eBands[i], eBands[i], B);
-         if (qb==0)
-            point_stereo_mix(m, P, bandE, i, 1);
-         else
-            stereo_band_mix(m, P, bandE, 0, i, 1);
-         deinterleave(P+C*eBands[i], C*N);
-
-         /*for (j=C*eBands[i];j<C*eBands[i+1];j++)
-            P[j] = 0;*/
-      } else if (pitch_used && eBands[i] < m->pitchEnd) {
-         if (qb==0)
-            point_stereo_mix(m, P, bandE, i, 1);
-         else
-            stereo_band_mix(m, P, bandE, 0, i, 1);
-         renormalise_vector(P+C*eBands[i], Q15ONE, N, C);
-         renormalise_vector(P+C*eBands[i]+1, Q15ONE, N, C);
-         deinterleave(P+C*eBands[i], C*N);
-         for (j=C*eBands[i];j<C*eBands[i+1];j++)
-            P[j] = MULT16_16_Q15(pgains[pband], P[j]);
-      } else {
-         for (j=C*eBands[i];j<C*eBands[i+1];j++)
-            P[j] = 0;
+         *remaining_bits += curr_bits;
+         q--;
+         curr_bits = pulses2bits(m->bits[LM][i], N, q);
+         *remaining_bits -= curr_bits;
       }
-      deinterleave(X+C*eBands[i], C*N);
-      if (q1 > 0)
-         alg_quant(X+C*eBands[i], W+C*eBands[i], N, q1, P+C*eBands[i], enc);
-      else
-         for (j=C*eBands[i];j<C*eBands[i]+N;j++)
-            X[j] = P[j];
-      if (q2 > 0)
-         alg_quant(X+C*eBands[i]+N, W+C*eBands[i], N, q2, P+C*eBands[i]+N, enc);
+
+      if (encode)
+         alg_quant(X, N, q, spread, lowband, resynth, (ec_enc*)ec);
       else
-         for (j=C*eBands[i]+N;j<C*eBands[i+1];j++)
-            X[j] = 0;
-      /*   orthogonalize(X+C*eBands[i], X+C*eBands[i]+N, N);*/
+         alg_unquant(X, N, q, spread, lowband, (ec_dec*)ec);
+   }
 
+   /* This code is used by the decoder and by the resynthesis-enabled encoder */
+   if (resynth)
+   {
+      int k;
 
+      if (split)
+      {
+         int j;
+         celt_word16 mid, side;
 #ifdef FIXED_POINT
-      mid = imid;
-      side = iside;
+         mid = imid;
+         side = iside;
 #else
-      mid = (1./32768)*imid;
-      side = (1./32768)*iside;
+         mid = (1.f/32768)*imid;
+         side = (1.f/32768)*iside;
 #endif
-      for (j=0;j<N;j++)
-         X[C*eBands[i]+j] = MULT16_16_Q15(X[C*eBands[i]+j], mid);
-      for (j=0;j<N;j++)
-         X[C*eBands[i]+N+j] = MULT16_16_Q15(X[C*eBands[i]+N+j], side);
-
-      interleave(X+C*eBands[i], C*N);
-
-      stereo_band_mix(m, X, bandE, 0, i, -1);
-      renormalise_vector(X+C*eBands[i], Q15ONE, N, C);
-      renormalise_vector(X+C*eBands[i]+1, Q15ONE, N, C);
-      for (j=0;j<C*N;j++)
-         norm[eBands[i]+j] = MULT16_16_Q15(n,X[C*eBands[i]+j]);
+         for (j=0;j<N;j++)
+            X[j] = MULT16_16_Q15(X[j], mid);
+         for (j=0;j<N;j++)
+            Y[j] = MULT16_16_Q15(Y[j], side);
       }
-   }
-   RESTORE_STACK;
-}
-
-/* Decoding of the residual */
-void unquant_bands(const CELTMode *m, celt_norm_t * restrict X, celt_norm_t *P, int pitch_used, celt_pgain_t *pgains, const celt_ener_t *bandE, int *pulses, int shortBlocks, int fold, int total_bits, ec_dec *dec)
-{
-   int i, j, remaining_bits, balance;
-   const celt_int16_t * restrict eBands = m->eBands;
-   celt_norm_t * restrict norm;
-   VARDECL(celt_norm_t, _norm);
-   const celt_int16_t *pBands = m->pBands;
-   int pband=-1;
-   int B;
-   SAVE_STACK;
-
-   B = shortBlocks ? m->nbShortMdcts : 1;
-   ALLOC(_norm, eBands[m->nbEBands+1], celt_norm_t);
-   norm = _norm;
-
-   balance = 0;
-   for (i=0;i<m->nbEBands;i++)
-   {
-      int tell;
-      int q;
-      celt_word16_t n;
-      const celt_int16_t * const *BPbits;
-      
-      int curr_balance, curr_bits;
-      
-      BPbits = m->bits;
 
-      tell = ec_dec_tell(dec, 4);
-      if (i != 0)
-         balance -= tell;
-      remaining_bits = (total_bits<<BITRES)-tell-1;
-      curr_balance = (m->nbEBands-i);
-      if (curr_balance > 3)
-         curr_balance = 3;
-      curr_balance = balance / curr_balance;
-      q = bits2pulses(m, BPbits[i], pulses[i]+curr_balance);
-      curr_bits = BPbits[i][q];
-      remaining_bits -= curr_bits;
-      while (remaining_bits < 0 && q > 0)
+      if (!stereo && spread0>1 && level==0)
       {
-         remaining_bits += curr_bits;
-         q--;
-         curr_bits = BPbits[i][q];
-         remaining_bits -= curr_bits;
+         interleave_vector(X, N_B, spread0);
+         if (lowband)
+            interleave_vector(lowband, N_B, spread0);
       }
-      balance += pulses[i] + tell;
 
-      n = SHL16(celt_sqrt(eBands[i+1]-eBands[i]),11);
+      /* Undo time-freq changes that we did earlier */
+      N_B = N_B0;
+      spread = spread0;
+      for (k=0;k<time_divide;k++)
+      {
+         spread >>= 1;
+         N_B <<= 1;
+         haar1(X, N_B, spread);
+         if (lowband)
+            haar1(lowband, N_B, spread);
+      }
 
-      /* If pitch is in use and this eBand begins a pitch band, encode the pitch gain flag */
-      if (pitch_used && eBands[i] < m->pitchEnd && eBands[i] == pBands[pband+1])
+      for (k=0;k<recombine;k++)
       {
-         int enabled = 1;
-         pband++;
-         if (remaining_bits >= 1<<BITRES) {
-           enabled = ec_dec_bits(dec, 1);
-           balance += 1<<BITRES;
-         }
-         if (enabled)
-            pgains[pband] = QCONST16(.9,15);
-         else
-            pgains[pband] = 0;
+         haar1(X, N_B, spread);
+         if (lowband)
+            haar1(lowband, N_B, spread);
+         N_B>>=1;
+         spread <<= 1;
       }
 
-      /* If pitch isn't available, use intra-frame prediction */
-      if ((eBands[i] >= m->pitchEnd && fold) || q<=0)
+      if (lowband_out && !stereo)
       {
-         intra_fold(m, X+eBands[i], eBands[i+1]-eBands[i], q, norm, P+eBands[i], eBands[i], B);
-      } else if (pitch_used && eBands[i] < m->pitchEnd) {
-         for (j=eBands[i];j<eBands[i+1];j++)
-            P[j] = MULT16_16_Q15(pgains[pband], P[j]);
-      } else {
-         for (j=eBands[i];j<eBands[i+1];j++)
-            P[j] = 0;
+         int j;
+         celt_word16 n;
+         n = celt_sqrt(SHL32(EXTEND32(N0),22));
+         for (j=0;j<N0;j++)
+            lowband_out[j] = MULT16_16_Q15(n,X[j]);
       }
-      
-      if (q > 0)
+
+      if (stereo)
       {
-         alg_unquant(X+eBands[i], eBands[i+1]-eBands[i], q, P+eBands[i], dec);
-      } else {
-         for (j=eBands[i];j<eBands[i+1];j++)
-            X[j] = P[j];
+         stereo_band_mix(m, X, Y, bandE, 0, i, -1, N);
+         renormalise_vector(X, Q15ONE, N, 1);
+         renormalise_vector(Y, Q15ONE, N, 1);
       }
-      for (j=eBands[i];j<eBands[i+1];j++)
-         norm[j] = MULT16_16_Q15(n,X[j]);
    }
-   RESTORE_STACK;
 }
 
-void unquant_bands_stereo(const CELTMode *m, celt_norm_t * restrict X, celt_norm_t *P, int pitch_used, celt_pgain_t *pgains, const celt_ener_t *bandE, int *pulses, int shortBlocks, int fold, int total_bits, ec_dec *dec)
+void quant_all_bands(int encode, const CELTMode *m, int start, celt_norm *_X, celt_norm *_Y, const celt_ener *bandE, int *pulses, int shortBlocks, int fold, int *tf_res, int resynth, int total_bits, void *ec, int LM)
 {
-   int i, j, remaining_bits, balance;
-   const celt_int16_t * restrict eBands = m->eBands;
-   celt_norm_t * restrict norm;
-   VARDECL(celt_norm_t, _norm);
-   const int C = CHANNELS(m);
-   const celt_int16_t *pBands = m->pBands;
-   int pband=-1;
+   int i, remaining_bits, balance;
+   const celt_int16 * restrict eBands = m->eBands;
+   celt_norm * restrict norm;
+   VARDECL(celt_norm, _norm);
    int B;
-   celt_word16_t mid, side;
+   int M;
+   int spread;
+   celt_norm *lowband;
+   int update_lowband = 1;
+   int C = _Y != NULL ? 2 : 1;
    SAVE_STACK;
 
-   B = shortBlocks ? m->nbShortMdcts : 1;
-   ALLOC(_norm, C*eBands[m->nbEBands+1], celt_norm_t);
+   M = 1<<LM;
+   B = shortBlocks ? M : 1;
+   spread = fold ? B : 0;
+   ALLOC(_norm, M*eBands[m->nbEBands+1], celt_norm);
    norm = _norm;
 
    balance = 0;
-   /*printf("bits left: %d\n", bits);
-   for (i=0;i<m->nbEBands;i++)
-   printf ("(%d %d) ", pulses[i], ebits[i]);
-   printf ("\n");*/
-   /*printf ("%d %d\n", ec_enc_tell(enc, 0), compute_allocation(m, m->nbPulses));*/
-   for (i=0;i<m->nbEBands;i++)
+   lowband = NULL;
+   for (i=start;i<m->nbEBands;i++)
    {
       int tell;
-      int q1, q2;
-      celt_word16_t n;
-      const celt_int16_t * const *BPbits;
-      int b, qb;
+      int b;
       int N;
-      int curr_balance, curr_bits;
-      int imid, iside, itheta;
-      int mbits, sbits, delta;
-      int qalloc;
+      int curr_balance;
+      celt_norm * restrict X, * restrict Y;
+      int tf_change=0;
       
-      BPbits = m->bits;
+      X = _X+M*eBands[i];
+      if (_Y!=NULL)
+         Y = _Y+M*eBands[i];
+      else
+         Y = NULL;
+      N = M*eBands[i+1]-M*eBands[i];
+      if (encode)
+         tell = ec_enc_tell((ec_enc*)ec, BITRES);
+      else
+         tell = ec_dec_tell((ec_dec*)ec, BITRES);
 
-      N = eBands[i+1]-eBands[i];
-      tell = ec_dec_tell(dec, 4);
-      if (i != 0)
+      if (i != start)
          balance -= tell;
       remaining_bits = (total_bits<<BITRES)-tell-1;
       curr_balance = (m->nbEBands-i);
@@ -895,196 +936,25 @@ void unquant_bands_stereo(const CELTMode *m, celt_norm_t * restrict X, celt_norm
       b = IMIN(remaining_bits+1,pulses[i]+curr_balance);
       if (b<0)
          b = 0;
-      
-      if (N<5) {
-         
-         q1 = bits2pulses(m, BPbits[i], b/2);
-         curr_bits = 2*BPbits[i][q1];
-         remaining_bits -= curr_bits;
-         while (remaining_bits < 0 && q1 > 0)
-         {
-            remaining_bits += curr_bits;
-            q1--;
-            curr_bits = 2*BPbits[i][q1];
-            remaining_bits -= curr_bits;
-         }
-         balance += pulses[i] + tell;
-         
-         n = SHL16(celt_sqrt((eBands[i+1]-eBands[i])),11);
-         
-         /* If pitch is in use and this eBand begins a pitch band, encode the pitch gain flag */
-         if (pitch_used && eBands[i]< m->pitchEnd && eBands[i] == pBands[pband+1])
-         {
-            int enabled = 1;
-            pband++;
-            if (remaining_bits >= 1<<BITRES) {
-               enabled = pgains[pband] > QCONST16(.5,15);
-               enabled = ec_dec_bits(dec, 1);
-               balance += 1<<BITRES;
-            }
-            if (enabled)
-               pgains[pband] = QCONST16(.9,15);
-            else
-               pgains[pband] = 0;
-         }
-         
-         /* If pitch isn't available, use intra-frame prediction */
-         if ((eBands[i] >= m->pitchEnd && fold) || q1<=0)
-         {
-            intra_fold(m, X+C*eBands[i], eBands[i+1]-eBands[i], q1, norm, P+C*eBands[i], eBands[i], B);
-            deinterleave(P+C*eBands[i], C*N);
-         } else if (pitch_used && eBands[i] < m->pitchEnd) {
-            deinterleave(P+C*eBands[i], C*N);
-            for (j=C*eBands[i];j<C*eBands[i+1];j++)
-               P[j] = MULT16_16_Q15(pgains[pband], P[j]);
-         } else {
-            for (j=C*eBands[i];j<C*eBands[i+1];j++)
-               P[j] = 0;
-         }
-         if (q1 > 0)
-         {
-            alg_unquant(X+C*eBands[i], N, q1, P+C*eBands[i], dec);
-            alg_unquant(X+C*eBands[i]+N, N, q1, P+C*eBands[i]+N, dec);
-         } else {
-            for (j=C*eBands[i];j<C*eBands[i+1];j++)
-               X[j] = P[j];
-         }
-         
-         interleave(X+C*eBands[i], C*N);
-         for (j=0;j<C*N;j++)
-            norm[eBands[i]+j] = MULT16_16_Q15(n,X[C*eBands[i]+j]);
+      /* Prevents ridiculous bit depths */
+      if (b > C*16*N<<BITRES)
+         b = C*16*N<<BITRES;
 
-      } else {
-      
-      qb = (b-2*(N-1)*(40-log2_frac(N,4)))/(32*(N-1));
-      if (qb > (b>>BITRES)-1)
-         qb = (b>>BITRES)-1;
-      if (qb<0)
-         qb = 0;
-      qalloc = log2_frac((1<<qb)+1,4);
-      if (qb==0)
-      {
-         itheta=0;
-      } else {
-         int shift;
-         shift = 14-qb;
-         itheta = ec_dec_uint(dec, (1<<qb)+1);
-         itheta <<= shift;
-      }
-      if (itheta == 0)
-      {
-         imid = 32767;
-         iside = 0;
-         delta = -10000;
-      } else if (itheta == 16384)
-      {
-         imid = 0;
-         iside = 32767;
-         delta = 10000;
-      } else {
-         imid = bitexact_cos(itheta);
-         iside = bitexact_cos(16384-itheta);
-         delta = (N-1)*(log2_frac(iside,6)-log2_frac(imid,6))>>2;
-      }
-      mbits = (b-qalloc/2-delta)/2;
-      if (mbits > b-qalloc)
-         mbits = b-qalloc;
-      if (mbits<0)
-         mbits=0;
-      sbits = b-qalloc-mbits;
-      q1 = bits2pulses(m, BPbits[i], mbits);
-      q2 = bits2pulses(m, BPbits[i], sbits);
-      curr_bits = BPbits[i][q1]+BPbits[i][q2]+qalloc;
-      remaining_bits -= curr_bits;
-      while (remaining_bits < 0 && (q1 > 0 || q2 > 0))
+      if (M*eBands[i]-N >= M*eBands[start])
       {
-         remaining_bits += curr_bits;
-         if (q1>q2)
-         {
-            q1--;
-            curr_bits = BPbits[i][q1]+BPbits[i][q2]+qalloc;
-         } else {
-            q2--;
-            curr_bits = BPbits[i][q1]+BPbits[i][q2]+qalloc;
-         }
-         remaining_bits -= curr_bits;
-      }
-      balance += pulses[i] + tell;
-      
-      n = SHL16(celt_sqrt((eBands[i+1]-eBands[i])),11);
+         if (update_lowband)
+            lowband = norm+M*eBands[i]-N;
+      } else
+         lowband = NULL;
 
-      /* If pitch is in use and this eBand begins a pitch band, encode the pitch gain flag */
-      if (pitch_used && eBands[i]< m->pitchEnd && eBands[i] == pBands[pband+1])
-      {
-         int enabled = 1;
-         pband++;
-         if (remaining_bits >= 1<<BITRES) {
-            enabled = pgains[pband] > QCONST16(.5,15);
-            enabled = ec_dec_bits(dec, 1);
-            balance += 1<<BITRES;
-         }
-         if (enabled)
-            pgains[pband] = QCONST16(.9,15);
-         else
-            pgains[pband] = 0;
-      }
+      tf_change = tf_res[i];
+      quant_band(encode, m, i, X, Y, N, b, spread, tf_change, lowband, resynth, ec, &remaining_bits, LM, norm+M*eBands[i], bandE, 0);
 
-      /* If pitch isn't available, use intra-frame prediction */
-      if ((eBands[i] >= m->pitchEnd && fold) || (q1+q2)<=0)
-      {
-         intra_fold(m, X+C*eBands[i], eBands[i+1]-eBands[i], q1+q2, norm, P+C*eBands[i], eBands[i], B);
-         if (qb==0)
-            point_stereo_mix(m, P, bandE, i, 1);
-         else
-            stereo_band_mix(m, P, bandE, 0, i, 1);
-         deinterleave(P+C*eBands[i], C*N);
-      } else if (pitch_used && eBands[i] < m->pitchEnd) {
-         if (qb==0)
-            point_stereo_mix(m, P, bandE, i, 1);
-         else
-            stereo_band_mix(m, P, bandE, 0, i, 1);
-         renormalise_vector(P+C*eBands[i], Q15ONE, N, C);
-         renormalise_vector(P+C*eBands[i]+1, Q15ONE, N, C);
-         deinterleave(P+C*eBands[i], C*N);
-         for (j=C*eBands[i];j<C*eBands[i+1];j++)
-            P[j] = MULT16_16_Q15(pgains[pband], P[j]);
-      } else {
-         for (j=C*eBands[i];j<C*eBands[i+1];j++)
-            P[j] = 0;
-      }
-      deinterleave(X+C*eBands[i], C*N);
-      if (q1 > 0)
-         alg_unquant(X+C*eBands[i], N, q1, P+C*eBands[i], dec);
-      else
-         for (j=C*eBands[i];j<C*eBands[i]+N;j++)
-            X[j] = P[j];
-      if (q2 > 0)
-         alg_unquant(X+C*eBands[i]+N, N, q2, P+C*eBands[i]+N, dec);
-      else
-         for (j=C*eBands[i]+N;j<C*eBands[i+1];j++)
-            X[j] = 0;
-      /*orthogonalize(X+C*eBands[i], X+C*eBands[i]+N, N);*/
-      
-#ifdef FIXED_POINT
-      mid = imid;
-      side = iside;
-#else
-      mid = (1./32768)*imid;
-      side = (1./32768)*iside;
-#endif
-      for (j=0;j<N;j++)
-         X[C*eBands[i]+j] = MULT16_16_Q15(X[C*eBands[i]+j], mid);
-      for (j=0;j<N;j++)
-         X[C*eBands[i]+N+j] = MULT16_16_Q15(X[C*eBands[i]+N+j], side);
-      
-      interleave(X+C*eBands[i], C*N);
+      balance += pulses[i] + tell;
 
-      stereo_band_mix(m, X, bandE, 0, i, -1);
-      renormalise_vector(X+C*eBands[i], Q15ONE, N, C);
-      renormalise_vector(X+C*eBands[i]+1, Q15ONE, N, C);
-      for (j=0;j<C*N;j++)
-         norm[eBands[i]+j] = MULT16_16_Q15(n,X[C*eBands[i]+j]);
-      }
+      /* Update the folding position only as long as we have 2 bit/sample depth */
+      update_lowband = (b>>BITRES)>2*N;
    }
    RESTORE_STACK;
 }
+