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diff --git a/drivers/theora/enquant.c b/drivers/theora/enquant.c
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+/********************************************************************
+ *                                                                  *
+ * THIS FILE IS PART OF THE OggTheora SOFTWARE CODEC SOURCE CODE.   *
+ * USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS     *
+ * GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE *
+ * IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING.       *
+ *                                                                  *
+ * THE Theora SOURCE CODE IS COPYRIGHT (C) 2002-2009                *
+ * by the Xiph.Org Foundation http://www.xiph.org/                  *
+ *                                                                  *
+ ********************************************************************
+
+  function:
+  last mod: $Id: enquant.c 16503 2009-08-22 18:14:02Z giles $
+
+ ********************************************************************/
+#include <stdlib.h>
+#include <string.h>
+#include "encint.h"
+
+
+
+void oc_quant_params_pack(oggpack_buffer *_opb,const th_quant_info *_qinfo){
+  const th_quant_ranges *qranges;
+  const th_quant_base   *base_mats[2*3*64];
+  int                    indices[2][3][64];
+  int                    nbase_mats;
+  int                    nbits;
+  int                    ci;
+  int                    qi;
+  int                    qri;
+  int                    qti;
+  int                    pli;
+  int                    qtj;
+  int                    plj;
+  int                    bmi;
+  int                    i;
+  i=_qinfo->loop_filter_limits[0];
+  for(qi=1;qi<64;qi++)i=OC_MAXI(i,_qinfo->loop_filter_limits[qi]);
+  nbits=OC_ILOG_32(i);
+  oggpackB_write(_opb,nbits,3);
+  for(qi=0;qi<64;qi++){
+    oggpackB_write(_opb,_qinfo->loop_filter_limits[qi],nbits);
+  }
+  /*580 bits for VP3.*/
+  i=1;
+  for(qi=0;qi<64;qi++)i=OC_MAXI(_qinfo->ac_scale[qi],i);
+  nbits=OC_ILOGNZ_32(i);
+  oggpackB_write(_opb,nbits-1,4);
+  for(qi=0;qi<64;qi++)oggpackB_write(_opb,_qinfo->ac_scale[qi],nbits);
+  /*516 bits for VP3.*/
+  i=1;
+  for(qi=0;qi<64;qi++)i=OC_MAXI(_qinfo->dc_scale[qi],i);
+  nbits=OC_ILOGNZ_32(i);
+  oggpackB_write(_opb,nbits-1,4);
+  for(qi=0;qi<64;qi++)oggpackB_write(_opb,_qinfo->dc_scale[qi],nbits);
+  /*Consolidate any duplicate base matrices.*/
+  nbase_mats=0;
+  for(qti=0;qti<2;qti++)for(pli=0;pli<3;pli++){
+    qranges=_qinfo->qi_ranges[qti]+pli;
+    for(qri=0;qri<=qranges->nranges;qri++){
+      for(bmi=0;;bmi++){
+        if(bmi>=nbase_mats){
+          base_mats[bmi]=qranges->base_matrices+qri;
+          indices[qti][pli][qri]=nbase_mats++;
+          break;
+        }
+        else if(memcmp(base_mats[bmi][0],qranges->base_matrices[qri],
+         sizeof(base_mats[bmi][0]))==0){
+          indices[qti][pli][qri]=bmi;
+          break;
+        }
+      }
+    }
+  }
+  /*Write out the list of unique base matrices.
+    1545 bits for VP3 matrices.*/
+  oggpackB_write(_opb,nbase_mats-1,9);
+  for(bmi=0;bmi<nbase_mats;bmi++){
+    for(ci=0;ci<64;ci++)oggpackB_write(_opb,base_mats[bmi][0][ci],8);
+  }
+  /*Now store quant ranges and their associated indices into the base matrix
+     list.
+    46 bits for VP3 matrices.*/
+  nbits=OC_ILOG_32(nbase_mats-1);
+  for(i=0;i<6;i++){
+    qti=i/3;
+    pli=i%3;
+    qranges=_qinfo->qi_ranges[qti]+pli;
+    if(i>0){
+      if(qti>0){
+        if(qranges->nranges==_qinfo->qi_ranges[qti-1][pli].nranges&&
+         memcmp(qranges->sizes,_qinfo->qi_ranges[qti-1][pli].sizes,
+         qranges->nranges*sizeof(qranges->sizes[0]))==0&&
+         memcmp(indices[qti][pli],indices[qti-1][pli],
+         (qranges->nranges+1)*sizeof(indices[qti][pli][0]))==0){
+          oggpackB_write(_opb,1,2);
+          continue;
+        }
+      }
+      qtj=(i-1)/3;
+      plj=(i-1)%3;
+      if(qranges->nranges==_qinfo->qi_ranges[qtj][plj].nranges&&
+       memcmp(qranges->sizes,_qinfo->qi_ranges[qtj][plj].sizes,
+       qranges->nranges*sizeof(qranges->sizes[0]))==0&&
+       memcmp(indices[qti][pli],indices[qtj][plj],
+       (qranges->nranges+1)*sizeof(indices[qti][pli][0]))==0){
+        oggpackB_write(_opb,0,1+(qti>0));
+        continue;
+      }
+      oggpackB_write(_opb,1,1);
+    }
+    oggpackB_write(_opb,indices[qti][pli][0],nbits);
+    for(qi=qri=0;qi<63;qri++){
+      oggpackB_write(_opb,qranges->sizes[qri]-1,OC_ILOG_32(62-qi));
+      qi+=qranges->sizes[qri];
+      oggpackB_write(_opb,indices[qti][pli][qri+1],nbits);
+    }
+  }
+}
+
+static void oc_iquant_init(oc_iquant *_this,ogg_uint16_t _d){
+  ogg_uint32_t t;
+  int          l;
+  _d<<=1;
+  l=OC_ILOGNZ_32(_d)-1;
+  t=1+((ogg_uint32_t)1<<16+l)/_d;
+  _this->m=(ogg_int16_t)(t-0x10000);
+  _this->l=l;
+}
+
+/*See comments at oc_dequant_tables_init() for how the quantization tables'
+   storage should be initialized.*/
+void oc_enquant_tables_init(ogg_uint16_t *_dequant[64][3][2],
+ oc_iquant *_enquant[64][3][2],const th_quant_info *_qinfo){
+  int qi;
+  int pli;
+  int qti;
+  /*Initialize the dequantization tables first.*/
+  oc_dequant_tables_init(_dequant,NULL,_qinfo);
+  /*Derive the quantization tables directly from the dequantization tables.*/
+  for(qi=0;qi<64;qi++)for(qti=0;qti<2;qti++)for(pli=0;pli<3;pli++){
+    int zzi;
+    int plj;
+    int qtj;
+    int dupe;
+    dupe=0;
+    for(qtj=0;qtj<=qti;qtj++){
+      for(plj=0;plj<(qtj<qti?3:pli);plj++){
+        if(_dequant[qi][pli][qti]==_dequant[qi][plj][qtj]){
+          dupe=1;
+          break;
+        }
+      }
+      if(dupe)break;
+    }
+    if(dupe){
+      _enquant[qi][pli][qti]=_enquant[qi][plj][qtj];
+      continue;
+    }
+    /*In the original VP3.2 code, the rounding offset and the size of the
+       dead zone around 0 were controlled by a "sharpness" parameter.
+      We now R-D optimize the tokens for each block after quantization,
+       so the rounding offset should always be 1/2, and an explicit dead
+       zone is unnecessary.
+      Hence, all of that VP3.2 code is gone from here, and the remaining
+       floating point code has been implemented as equivalent integer
+       code with exact precision.*/
+    for(zzi=0;zzi<64;zzi++){
+      oc_iquant_init(_enquant[qi][pli][qti]+zzi,
+       _dequant[qi][pli][qti][zzi]);
+    }
+  }
+}
+
+
+
+/*This table gives the square root of the fraction of the squared magnitude of
+   each DCT coefficient relative to the total, scaled by 2**16, for both INTRA
+   and INTER modes.
+  These values were measured after motion-compensated prediction, before
+   quantization, over a large set of test video (from QCIF to 1080p) encoded at
+   all possible rates.
+  The DC coefficient takes into account the DPCM prediction (using the
+   quantized values from neighboring blocks, as the encoder does, but still
+   before quantization of the coefficient in the current block).
+  The results differ significantly from the expected variance (e.g., using an
+   AR(1) model of the signal with rho=0.95, as is frequently done to compute
+   the coding gain of the DCT).
+  We use them to estimate an "average" quantizer for a given quantizer matrix,
+   as this is used to parameterize a number of the rate control decisions.
+  These values are themselves probably quantizer-matrix dependent, since the
+   shape of the matrix affects the noise distribution in the reference frames,
+   but they should at least give us _some_ amount of adaptivity to different
+   matrices, as opposed to hard-coding a table of average Q values for the
+   current set.
+  The main features they capture are that a) only a few of the quantizers in
+   the upper-left corner contribute anything significant at all (though INTER
+   mode is significantly flatter) and b) the DPCM prediction of the DC
+   coefficient gives a very minor improvement in the INTRA case and a quite
+   significant one in the INTER case (over the expected variance).*/
+static const ogg_uint16_t OC_RPSD[2][64]={
+  {
+    52725,17370,10399, 6867, 5115, 3798, 2942, 2076,
+    17370, 9900, 6948, 4994, 3836, 2869, 2229, 1619,
+    10399, 6948, 5516, 4202, 3376, 2573, 2015, 1461,
+     6867, 4994, 4202, 3377, 2800, 2164, 1718, 1243,
+     5115, 3836, 3376, 2800, 2391, 1884, 1530, 1091,
+     3798, 2869, 2573, 2164, 1884, 1495, 1212,  873,
+     2942, 2229, 2015, 1718, 1530, 1212, 1001,  704,
+     2076, 1619, 1461, 1243, 1091,  873,  704,  474
+  },
+  {
+    23411,15604,13529,11601,10683, 8958, 7840, 6142,
+    15604,11901,10718, 9108, 8290, 6961, 6023, 4487,
+    13529,10718, 9961, 8527, 7945, 6689, 5742, 4333,
+    11601, 9108, 8527, 7414, 7084, 5923, 5175, 3743,
+    10683, 8290, 7945, 7084, 6771, 5754, 4793, 3504,
+     8958, 6961, 6689, 5923, 5754, 4679, 3936, 2989,
+     7840, 6023, 5742, 5175, 4793, 3936, 3522, 2558,
+     6142, 4487, 4333, 3743, 3504, 2989, 2558, 1829
+  }
+};
+
+/*The fraction of the squared magnitude of the residuals in each color channel
+   relative to the total, scaled by 2**16, for each pixel format.
+  These values were measured after motion-compensated prediction, before
+   quantization, over a large set of test video encoded at all possible rates.
+  TODO: These values are only from INTER frames; it should be re-measured for
+   INTRA frames.*/
+static const ogg_uint16_t OC_PCD[4][3]={
+  {59926, 3038, 2572},
+  {55201, 5597, 4738},
+  {55201, 5597, 4738},
+  {47682, 9669, 8185}
+};
+
+
+/*Compute an "average" quantizer for each qi level.
+  We do one for INTER and one for INTRA, since their behavior is very
+   different, but average across chroma channels.
+  The basic approach is to compute a harmonic average of the squared quantizer,
+   weighted by the expected squared magnitude of the DCT coefficients.
+  Under the (not quite true) assumption that DCT coefficients are
+   Laplacian-distributed, this preserves the product Q*lambda, where
+   lambda=sqrt(2/sigma**2) is the Laplacian distribution parameter (not to be
+   confused with the lambda used in R-D optimization throughout most of the
+   rest of the code).
+  The value Q*lambda completely determines the entropy of the coefficients.*/
+void oc_enquant_qavg_init(ogg_int64_t _log_qavg[2][64],
+ ogg_uint16_t *_dequant[64][3][2],int _pixel_fmt){
+  int qi;
+  int pli;
+  int qti;
+  int ci;
+  for(qti=0;qti<2;qti++)for(qi=0;qi<64;qi++){
+    ogg_int64_t q2;
+    q2=0;
+    for(pli=0;pli<3;pli++){
+      ogg_uint32_t qp;
+      qp=0;
+      for(ci=0;ci<64;ci++){
+        unsigned rq;
+        unsigned qd;
+        qd=_dequant[qi][pli][qti][OC_IZIG_ZAG[ci]];
+        rq=(OC_RPSD[qti][ci]+(qd>>1))/qd;
+        qp+=rq*(ogg_uint32_t)rq;
+      }
+      q2+=OC_PCD[_pixel_fmt][pli]*(ogg_int64_t)qp;
+    }
+    /*qavg=1.0/sqrt(q2).*/
+    _log_qavg[qti][qi]=OC_Q57(48)-oc_blog64(q2)>>1;
+  }
+}