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diff --git a/src/libspeex/mdf.c b/src/libspeex/mdf.c
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+/* Copyright (C) 2003-2006 Jean-Marc Valin
+
+   File: mdf.c
+   Echo canceller based on the MDF algorithm (see below)
+
+   Redistribution and use in source and binary forms, with or without
+   modification, are permitted provided that the following conditions are
+   met:
+
+   1. Redistributions of source code must retain the above copyright notice,
+   this list of conditions and the following disclaimer.
+
+   2. 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.
+
+   3. The name of the author may not be used to endorse or promote products
+   derived from this software without specific prior written permission.
+
+   THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
+*/
+
+/*
+   The echo canceller is based on the MDF algorithm described in:
+
+   J. S. Soo, K. K. Pang Multidelay block frequency adaptive filter, 
+   IEEE Trans. Acoust. Speech Signal Process., Vol. ASSP-38, No. 2, 
+   February 1990.
+   
+   We use the Alternatively Updated MDF (AUMDF) variant. Robustness to 
+   double-talk is achieved using a variable learning rate as described in:
+   
+   Valin, J.-M., On Adjusting the Learning Rate in Frequency Domain Echo 
+   Cancellation With Double-Talk. IEEE Transactions on Audio,
+   Speech and Language Processing, Vol. 15, No. 3, pp. 1030-1034, 2007.
+   http://people.xiph.org/~jm/papers/valin_taslp2006.pdf
+   
+   There is no explicit double-talk detection, but a continuous variation
+   in the learning rate based on residual echo, double-talk and background
+   noise.
+   
+   About the fixed-point version:
+   All the signals are represented with 16-bit words. The filter weights 
+   are represented with 32-bit words, but only the top 16 bits are used
+   in most cases. The lower 16 bits are completely unreliable (due to the
+   fact that the update is done only on the top bits), but help in the
+   adaptation -- probably by removing a "threshold effect" due to
+   quantization (rounding going to zero) when the gradient is small.
+   
+   Another kludge that seems to work good: when performing the weight
+   update, we only move half the way toward the "goal" this seems to
+   reduce the effect of quantization noise in the update phase. This
+   can be seen as applying a gradient descent on a "soft constraint"
+   instead of having a hard constraint.
+   
+*/
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include "arch.h"
+#include "speex/speex_echo.h"
+#include "fftwrap.h"
+#include "pseudofloat.h"
+#include "math_approx.h"
+#include "os_support.h"
+
+#ifndef M_PI
+#define M_PI 3.14159265358979323846
+#endif
+
+#ifdef FIXED_POINT
+#define WEIGHT_SHIFT 11
+#define NORMALIZE_SCALEDOWN 5
+#define NORMALIZE_SCALEUP 3
+#else
+#define WEIGHT_SHIFT 0
+#endif
+
+/* If enabled, the AEC will use a foreground filter and a background filter to be more robust to double-talk
+   and difficult signals in general. The cost is an extra FFT and a matrix-vector multiply */
+#define TWO_PATH
+
+#ifdef FIXED_POINT
+static const spx_float_t MIN_LEAK = {20972, -22};
+
+/* Constants for the two-path filter */
+static const spx_float_t VAR1_SMOOTH = {23593, -16};
+static const spx_float_t VAR2_SMOOTH = {23675, -15};
+static const spx_float_t VAR1_UPDATE = {16384, -15};
+static const spx_float_t VAR2_UPDATE = {16384, -16};
+static const spx_float_t VAR_BACKTRACK = {16384, -12};
+#define TOP16(x) ((x)>>16)
+
+#else
+
+static const spx_float_t MIN_LEAK = .005f;
+
+/* Constants for the two-path filter */
+static const spx_float_t VAR1_SMOOTH = .36f;
+static const spx_float_t VAR2_SMOOTH = .7225f;
+static const spx_float_t VAR1_UPDATE = .5f;
+static const spx_float_t VAR2_UPDATE = .25f;
+static const spx_float_t VAR_BACKTRACK = 4.f;
+#define TOP16(x) (x)
+#endif
+
+
+#define PLAYBACK_DELAY 2
+
+void speex_echo_get_residual(SpeexEchoState *st, spx_word32_t *Yout, int len);
+
+
+/** Speex echo cancellation state. */
+struct SpeexEchoState_ {
+   int frame_size;           /**< Number of samples processed each time */
+   int window_size;
+   int M;
+   int cancel_count;
+   int adapted;
+   int saturated;
+   int screwed_up;
+   spx_int32_t sampling_rate;
+   spx_word16_t spec_average;
+   spx_word16_t beta0;
+   spx_word16_t beta_max;
+   spx_word32_t sum_adapt;
+   spx_word16_t leak_estimate;
+   
+   spx_word16_t *e;      /* scratch */
+   spx_word16_t *x;      /* Far-end input buffer (2N) */
+   spx_word16_t *X;      /* Far-end buffer (M+1 frames) in frequency domain */
+   spx_word16_t *input;  /* scratch */
+   spx_word16_t *y;      /* scratch */
+   spx_word16_t *last_y;
+   spx_word16_t *Y;      /* scratch */
+   spx_word16_t *E;
+   spx_word32_t *PHI;    /* scratch */
+   spx_word32_t *W;      /* (Background) filter weights */
+#ifdef TWO_PATH
+   spx_word16_t *foreground; /* Foreground filter weights */
+   spx_word32_t  Davg1;  /* 1st recursive average of the residual power difference */
+   spx_word32_t  Davg2;  /* 2nd recursive average of the residual power difference */
+   spx_float_t   Dvar1;  /* Estimated variance of 1st estimator */
+   spx_float_t   Dvar2;  /* Estimated variance of 2nd estimator */
+#endif
+   spx_word32_t *power;  /* Power of the far-end signal */
+   spx_float_t  *power_1;/* Inverse power of far-end */
+   spx_word16_t *wtmp;   /* scratch */
+#ifdef FIXED_POINT
+   spx_word16_t *wtmp2;  /* scratch */
+#endif
+   spx_word32_t *Rf;     /* scratch */
+   spx_word32_t *Yf;     /* scratch */
+   spx_word32_t *Xf;     /* scratch */
+   spx_word32_t *Eh;
+   spx_word32_t *Yh;
+   spx_float_t   Pey;
+   spx_float_t   Pyy;
+   spx_word16_t *window;
+   spx_word16_t *prop;
+   void *fft_table;
+   spx_word16_t memX, memD, memE;
+   spx_word16_t preemph;
+   spx_word16_t notch_radius;
+   spx_mem_t notch_mem[2];
+
+   /* NOTE: If you only use speex_echo_cancel() and want to save some memory, remove this */
+   spx_int16_t *play_buf;
+   int play_buf_pos;
+   int play_buf_started;
+};
+
+static inline void filter_dc_notch16(const spx_int16_t *in, spx_word16_t radius, spx_word16_t *out, int len, spx_mem_t *mem)
+{
+   int i;
+   spx_word16_t den2;
+#ifdef FIXED_POINT
+   den2 = MULT16_16_Q15(radius,radius) + MULT16_16_Q15(QCONST16(.7,15),MULT16_16_Q15(32767-radius,32767-radius));
+#else
+   den2 = radius*radius + .7*(1-radius)*(1-radius);
+#endif   
+   /*printf ("%d %d %d %d %d %d\n", num[0], num[1], num[2], den[0], den[1], den[2]);*/
+   for (i=0;i<len;i++)
+   {
+      spx_word16_t vin = in[i];
+      spx_word32_t vout = mem[0] + SHL32(EXTEND32(vin),15);
+#ifdef FIXED_POINT
+      mem[0] = mem[1] + SHL32(SHL32(-EXTEND32(vin),15) + MULT16_32_Q15(radius,vout),1);
+#else
+      mem[0] = mem[1] + 2*(-vin + radius*vout);
+#endif
+      mem[1] = SHL32(EXTEND32(vin),15) - MULT16_32_Q15(den2,vout);
+      out[i] = SATURATE32(PSHR32(MULT16_32_Q15(radius,vout),15),32767);
+   }
+}
+
+/* This inner product is slightly different from the codec version because of fixed-point */
+static inline spx_word32_t mdf_inner_prod(const spx_word16_t *x, const spx_word16_t *y, int len)
+{
+   spx_word32_t sum=0;
+   len >>= 1;
+   while(len--)
+   {
+      spx_word32_t part=0;
+      part = MAC16_16(part,*x++,*y++);
+      part = MAC16_16(part,*x++,*y++);
+      /* HINT: If you had a 40-bit accumulator, you could shift only at the end */
+      sum = ADD32(sum,SHR32(part,6));
+   }
+   return sum;
+}
+
+/** Compute power spectrum of a half-complex (packed) vector */
+static inline void power_spectrum(const spx_word16_t *X, spx_word32_t *ps, int N)
+{
+   int i, j;
+   ps[0]=MULT16_16(X[0],X[0]);
+   for (i=1,j=1;i<N-1;i+=2,j++)
+   {
+      ps[j] =  MULT16_16(X[i],X[i]) + MULT16_16(X[i+1],X[i+1]);
+   }
+   ps[j]=MULT16_16(X[i],X[i]);
+}
+
+/** Compute cross-power spectrum of a half-complex (packed) vectors and add to acc */
+#ifdef FIXED_POINT
+static inline void spectral_mul_accum(const spx_word16_t *X, const spx_word32_t *Y, spx_word16_t *acc, int N, int M)
+{
+   int i,j;
+   spx_word32_t tmp1=0,tmp2=0;
+   for (j=0;j<M;j++)
+   {
+      tmp1 = MAC16_16(tmp1, X[j*N],TOP16(Y[j*N]));
+   }
+   acc[0] = PSHR32(tmp1,WEIGHT_SHIFT);
+   for (i=1;i<N-1;i+=2)
+   {
+      tmp1 = tmp2 = 0;
+      for (j=0;j<M;j++)
+      {
+         tmp1 = SUB32(MAC16_16(tmp1, X[j*N+i],TOP16(Y[j*N+i])), MULT16_16(X[j*N+i+1],TOP16(Y[j*N+i+1])));
+         tmp2 = MAC16_16(MAC16_16(tmp2, X[j*N+i+1],TOP16(Y[j*N+i])), X[j*N+i], TOP16(Y[j*N+i+1]));
+      }
+      acc[i] = PSHR32(tmp1,WEIGHT_SHIFT);
+      acc[i+1] = PSHR32(tmp2,WEIGHT_SHIFT);
+   }
+   tmp1 = tmp2 = 0;
+   for (j=0;j<M;j++)
+   {
+      tmp1 = MAC16_16(tmp1, X[(j+1)*N-1],TOP16(Y[(j+1)*N-1]));
+   }
+   acc[N-1] = PSHR32(tmp1,WEIGHT_SHIFT);
+}
+static inline void spectral_mul_accum16(const spx_word16_t *X, const spx_word16_t *Y, spx_word16_t *acc, int N, int M)
+{
+   int i,j;
+   spx_word32_t tmp1=0,tmp2=0;
+   for (j=0;j<M;j++)
+   {
+      tmp1 = MAC16_16(tmp1, X[j*N],Y[j*N]);
+   }
+   acc[0] = PSHR32(tmp1,WEIGHT_SHIFT);
+   for (i=1;i<N-1;i+=2)
+   {
+      tmp1 = tmp2 = 0;
+      for (j=0;j<M;j++)
+      {
+         tmp1 = SUB32(MAC16_16(tmp1, X[j*N+i],Y[j*N+i]), MULT16_16(X[j*N+i+1],Y[j*N+i+1]));
+         tmp2 = MAC16_16(MAC16_16(tmp2, X[j*N+i+1],Y[j*N+i]), X[j*N+i], Y[j*N+i+1]);
+      }
+      acc[i] = PSHR32(tmp1,WEIGHT_SHIFT);
+      acc[i+1] = PSHR32(tmp2,WEIGHT_SHIFT);
+   }
+   tmp1 = tmp2 = 0;
+   for (j=0;j<M;j++)
+   {
+      tmp1 = MAC16_16(tmp1, X[(j+1)*N-1],Y[(j+1)*N-1]);
+   }
+   acc[N-1] = PSHR32(tmp1,WEIGHT_SHIFT);
+}
+
+#else
+static inline void spectral_mul_accum(const spx_word16_t *X, const spx_word32_t *Y, spx_word16_t *acc, int N, int M)
+{
+   int i,j;
+   for (i=0;i<N;i++)
+      acc[i] = 0;
+   for (j=0;j<M;j++)
+   {
+      acc[0] += X[0]*Y[0];
+      for (i=1;i<N-1;i+=2)
+      {
+         acc[i] += (X[i]*Y[i] - X[i+1]*Y[i+1]);
+         acc[i+1] += (X[i+1]*Y[i] + X[i]*Y[i+1]);
+      }
+      acc[i] += X[i]*Y[i];
+      X += N;
+      Y += N;
+   }
+}
+#define spectral_mul_accum16 spectral_mul_accum
+#endif
+
+/** Compute weighted cross-power spectrum of a half-complex (packed) vector with conjugate */
+static inline void weighted_spectral_mul_conj(const spx_float_t *w, const spx_float_t p, const spx_word16_t *X, const spx_word16_t *Y, spx_word32_t *prod, int N)
+{
+   int i, j;
+   spx_float_t W;
+   W = FLOAT_AMULT(p, w[0]);
+   prod[0] = FLOAT_MUL32(W,MULT16_16(X[0],Y[0]));
+   for (i=1,j=1;i<N-1;i+=2,j++)
+   {
+      W = FLOAT_AMULT(p, w[j]);
+      prod[i] = FLOAT_MUL32(W,MAC16_16(MULT16_16(X[i],Y[i]), X[i+1],Y[i+1]));
+      prod[i+1] = FLOAT_MUL32(W,MAC16_16(MULT16_16(-X[i+1],Y[i]), X[i],Y[i+1]));
+   }
+   W = FLOAT_AMULT(p, w[j]);
+   prod[i] = FLOAT_MUL32(W,MULT16_16(X[i],Y[i]));
+}
+
+static inline void mdf_adjust_prop(const spx_word32_t *W, int N, int M, spx_word16_t *prop)
+{
+   int i, j;
+   spx_word16_t max_sum = 1;
+   spx_word32_t prop_sum = 1;
+   for (i=0;i<M;i++)
+   {
+      spx_word32_t tmp = 1;
+      for (j=0;j<N;j++)
+         tmp += MULT16_16(EXTRACT16(SHR32(W[i*N+j],18)), EXTRACT16(SHR32(W[i*N+j],18)));
+#ifdef FIXED_POINT
+      /* Just a security in case an overflow were to occur */
+      tmp = MIN32(ABS32(tmp), 536870912);
+#endif
+      prop[i] = spx_sqrt(tmp);
+      if (prop[i] > max_sum)
+         max_sum = prop[i];
+   }
+   for (i=0;i<M;i++)
+   {
+      prop[i] += MULT16_16_Q15(QCONST16(.1f,15),max_sum);
+      prop_sum += EXTEND32(prop[i]);
+   }
+   for (i=0;i<M;i++)
+   {
+      prop[i] = DIV32(MULT16_16(QCONST16(.99f,15), prop[i]),prop_sum);
+      /*printf ("%f ", prop[i]);*/
+   }
+   /*printf ("\n");*/
+}
+
+#ifdef DUMP_ECHO_CANCEL_DATA
+#include <stdio.h>
+static FILE *rFile=NULL, *pFile=NULL, *oFile=NULL;
+
+static void dump_audio(const spx_int16_t *rec, const spx_int16_t *play, const spx_int16_t *out, int len)
+{
+   if (!(rFile && pFile && oFile))
+   {
+      speex_fatal("Dump files not open");
+   }
+   fwrite(rec, sizeof(spx_int16_t), len, rFile);
+   fwrite(play, sizeof(spx_int16_t), len, pFile);
+   fwrite(out, sizeof(spx_int16_t), len, oFile);
+}
+#endif
+
+/** Creates a new echo canceller state */
+SpeexEchoState *speex_echo_state_init(int frame_size, int filter_length)
+{
+   int i,N,M;
+   SpeexEchoState *st = (SpeexEchoState *)speex_alloc(sizeof(SpeexEchoState));
+
+#ifdef DUMP_ECHO_CANCEL_DATA
+   if (rFile || pFile || oFile)
+      speex_fatal("Opening dump files twice");
+   rFile = fopen("aec_rec.sw", "wb");
+   pFile = fopen("aec_play.sw", "wb");
+   oFile = fopen("aec_out.sw", "wb");
+#endif
+   
+   st->frame_size = frame_size;
+   st->window_size = 2*frame_size;
+   N = st->window_size;
+   M = st->M = (filter_length+st->frame_size-1)/frame_size;
+   st->cancel_count=0;
+   st->sum_adapt = 0;
+   st->saturated = 0;
+   st->screwed_up = 0;
+   /* This is the default sampling rate */
+   st->sampling_rate = 8000;
+   st->spec_average = DIV32_16(SHL32(EXTEND32(st->frame_size), 15), st->sampling_rate);
+#ifdef FIXED_POINT
+   st->beta0 = DIV32_16(SHL32(EXTEND32(st->frame_size), 16), st->sampling_rate);
+   st->beta_max = DIV32_16(SHL32(EXTEND32(st->frame_size), 14), st->sampling_rate);
+#else
+   st->beta0 = (2.0f*st->frame_size)/st->sampling_rate;
+   st->beta_max = (.5f*st->frame_size)/st->sampling_rate;
+#endif
+   st->leak_estimate = 0;
+
+   st->fft_table = spx_fft_init(N);
+   
+   st->e = (spx_word16_t*)speex_alloc(N*sizeof(spx_word16_t));
+   st->x = (spx_word16_t*)speex_alloc(N*sizeof(spx_word16_t));
+   st->input = (spx_word16_t*)speex_alloc(st->frame_size*sizeof(spx_word16_t));
+   st->y = (spx_word16_t*)speex_alloc(N*sizeof(spx_word16_t));
+   st->last_y = (spx_word16_t*)speex_alloc(N*sizeof(spx_word16_t));
+   st->Yf = (spx_word32_t*)speex_alloc((st->frame_size+1)*sizeof(spx_word32_t));
+   st->Rf = (spx_word32_t*)speex_alloc((st->frame_size+1)*sizeof(spx_word32_t));
+   st->Xf = (spx_word32_t*)speex_alloc((st->frame_size+1)*sizeof(spx_word32_t));
+   st->Yh = (spx_word32_t*)speex_alloc((st->frame_size+1)*sizeof(spx_word32_t));
+   st->Eh = (spx_word32_t*)speex_alloc((st->frame_size+1)*sizeof(spx_word32_t));
+
+   st->X = (spx_word16_t*)speex_alloc((M+1)*N*sizeof(spx_word16_t));
+   st->Y = (spx_word16_t*)speex_alloc(N*sizeof(spx_word16_t));
+   st->E = (spx_word16_t*)speex_alloc(N*sizeof(spx_word16_t));
+   st->W = (spx_word32_t*)speex_alloc(M*N*sizeof(spx_word32_t));
+#ifdef TWO_PATH
+   st->foreground = (spx_word16_t*)speex_alloc(M*N*sizeof(spx_word16_t));
+#endif
+   st->PHI = (spx_word32_t*)speex_alloc(N*sizeof(spx_word32_t));
+   st->power = (spx_word32_t*)speex_alloc((frame_size+1)*sizeof(spx_word32_t));
+   st->power_1 = (spx_float_t*)speex_alloc((frame_size+1)*sizeof(spx_float_t));
+   st->window = (spx_word16_t*)speex_alloc(N*sizeof(spx_word16_t));
+   st->prop = (spx_word16_t*)speex_alloc(M*sizeof(spx_word16_t));
+   st->wtmp = (spx_word16_t*)speex_alloc(N*sizeof(spx_word16_t));
+#ifdef FIXED_POINT
+   st->wtmp2 = (spx_word16_t*)speex_alloc(N*sizeof(spx_word16_t));
+   for (i=0;i<N>>1;i++)
+   {
+      st->window[i] = (16383-SHL16(spx_cos(DIV32_16(MULT16_16(25736,i<<1),N)),1));
+      st->window[N-i-1] = st->window[i];
+   }
+#else
+   for (i=0;i<N;i++)
+      st->window[i] = .5-.5*cos(2*M_PI*i/N);
+#endif
+   for (i=0;i<=st->frame_size;i++)
+      st->power_1[i] = FLOAT_ONE;
+   for (i=0;i<N*M;i++)
+      st->W[i] = 0;
+   {
+      spx_word32_t sum = 0;
+      /* Ratio of ~10 between adaptation rate of first and last block */
+      spx_word16_t decay = SHR32(spx_exp(NEG16(DIV32_16(QCONST16(2.4,11),M))),1);
+      st->prop[0] = QCONST16(.7, 15);
+      sum = EXTEND32(st->prop[0]);
+      for (i=1;i<M;i++)
+      {
+         st->prop[i] = MULT16_16_Q15(st->prop[i-1], decay);
+         sum = ADD32(sum, EXTEND32(st->prop[i]));
+      }
+      for (i=M-1;i>=0;i--)
+      {
+         st->prop[i] = DIV32(MULT16_16(QCONST16(.8,15), st->prop[i]),sum);
+      }
+   }
+   
+   st->memX=st->memD=st->memE=0;
+   st->preemph = QCONST16(.9,15);
+   if (st->sampling_rate<12000)
+      st->notch_radius = QCONST16(.9, 15);
+   else if (st->sampling_rate<24000)
+      st->notch_radius = QCONST16(.982, 15);
+   else
+      st->notch_radius = QCONST16(.992, 15);
+
+   st->notch_mem[0] = st->notch_mem[1] = 0;
+   st->adapted = 0;
+   st->Pey = st->Pyy = FLOAT_ONE;
+   
+#ifdef TWO_PATH
+   st->Davg1 = st->Davg2 = 0;
+   st->Dvar1 = st->Dvar2 = FLOAT_ZERO;
+#endif
+   
+   st->play_buf = (spx_int16_t*)speex_alloc((PLAYBACK_DELAY+1)*st->frame_size*sizeof(spx_int16_t));
+   st->play_buf_pos = PLAYBACK_DELAY*st->frame_size;
+   st->play_buf_started = 0;
+   
+   return st;
+}
+
+/** Resets echo canceller state */
+void speex_echo_state_reset(SpeexEchoState *st)
+{
+   int i, M, N;
+   st->cancel_count=0;
+   st->screwed_up = 0;
+   N = st->window_size;
+   M = st->M;
+   for (i=0;i<N*M;i++)
+      st->W[i] = 0;
+#ifdef TWO_PATH
+   for (i=0;i<N*M;i++)
+      st->foreground[i] = 0;
+#endif
+   for (i=0;i<N*(M+1);i++)
+      st->X[i] = 0;
+   for (i=0;i<=st->frame_size;i++)
+   {
+      st->power[i] = 0;
+      st->power_1[i] = FLOAT_ONE;
+      st->Eh[i] = 0;
+      st->Yh[i] = 0;
+   }
+   for (i=0;i<st->frame_size;i++)
+   {
+      st->last_y[i] = 0;
+   }
+   for (i=0;i<N;i++)
+   {
+      st->E[i] = 0;
+      st->x[i] = 0;
+   }
+   st->notch_mem[0] = st->notch_mem[1] = 0;
+   st->memX=st->memD=st->memE=0;
+
+   st->saturated = 0;
+   st->adapted = 0;
+   st->sum_adapt = 0;
+   st->Pey = st->Pyy = FLOAT_ONE;
+#ifdef TWO_PATH
+   st->Davg1 = st->Davg2 = 0;
+   st->Dvar1 = st->Dvar2 = FLOAT_ZERO;
+#endif
+   for (i=0;i<3*st->frame_size;i++)
+      st->play_buf[i] = 0;
+   st->play_buf_pos = PLAYBACK_DELAY*st->frame_size;
+   st->play_buf_started = 0;
+
+}
+
+/** Destroys an echo canceller state */
+void speex_echo_state_destroy(SpeexEchoState *st)
+{
+   spx_fft_destroy(st->fft_table);
+
+   speex_free(st->e);
+   speex_free(st->x);
+   speex_free(st->input);
+   speex_free(st->y);
+   speex_free(st->last_y);
+   speex_free(st->Yf);
+   speex_free(st->Rf);
+   speex_free(st->Xf);
+   speex_free(st->Yh);
+   speex_free(st->Eh);
+
+   speex_free(st->X);
+   speex_free(st->Y);
+   speex_free(st->E);
+   speex_free(st->W);
+#ifdef TWO_PATH
+   speex_free(st->foreground);
+#endif
+   speex_free(st->PHI);
+   speex_free(st->power);
+   speex_free(st->power_1);
+   speex_free(st->window);
+   speex_free(st->prop);
+   speex_free(st->wtmp);
+#ifdef FIXED_POINT
+   speex_free(st->wtmp2);
+#endif
+   speex_free(st->play_buf);
+   speex_free(st);
+   
+#ifdef DUMP_ECHO_CANCEL_DATA
+   fclose(rFile);
+   fclose(pFile);
+   fclose(oFile);
+   rFile = pFile = oFile = NULL;
+#endif
+}
+
+void speex_echo_capture(SpeexEchoState *st, const spx_int16_t *rec, spx_int16_t *out)
+{
+   int i;
+   /*speex_warning_int("capture with fill level ", st->play_buf_pos/st->frame_size);*/
+   st->play_buf_started = 1;
+   if (st->play_buf_pos>=st->frame_size)
+   {
+      speex_echo_cancellation(st, rec, st->play_buf, out);
+      st->play_buf_pos -= st->frame_size;
+      for (i=0;i<st->play_buf_pos;i++)
+         st->play_buf[i] = st->play_buf[i+st->frame_size];
+   } else {
+      speex_warning("No playback frame available (your application is buggy and/or got xruns)");
+      if (st->play_buf_pos!=0)
+      {
+         speex_warning("internal playback buffer corruption?");
+         st->play_buf_pos = 0;
+      }
+      for (i=0;i<st->frame_size;i++)
+         out[i] = rec[i];
+   }
+}
+
+void speex_echo_playback(SpeexEchoState *st, const spx_int16_t *play)
+{
+   /*speex_warning_int("playback with fill level ", st->play_buf_pos/st->frame_size);*/
+   if (!st->play_buf_started)
+   {
+      speex_warning("discarded first playback frame");
+      return;
+   }
+   if (st->play_buf_pos<=PLAYBACK_DELAY*st->frame_size)
+   {
+      int i;
+      for (i=0;i<st->frame_size;i++)
+         st->play_buf[st->play_buf_pos+i] = play[i];
+      st->play_buf_pos += st->frame_size;
+      if (st->play_buf_pos <= (PLAYBACK_DELAY-1)*st->frame_size)
+      {
+         speex_warning("Auto-filling the buffer (your application is buggy and/or got xruns)");
+         for (i=0;i<st->frame_size;i++)
+            st->play_buf[st->play_buf_pos+i] = play[i];
+         st->play_buf_pos += st->frame_size;
+      }
+   } else {
+      speex_warning("Had to discard a playback frame (your application is buggy and/or got xruns)");
+   }
+}
+
+/** Performs echo cancellation on a frame (deprecated, last arg now ignored) */
+void speex_echo_cancel(SpeexEchoState *st, const spx_int16_t *in, const spx_int16_t *far_end, spx_int16_t *out, spx_int32_t *Yout)
+{
+   speex_echo_cancellation(st, in, far_end, out);
+}
+
+/** Performs echo cancellation on a frame */
+void speex_echo_cancellation(SpeexEchoState *st, const spx_int16_t *in, const spx_int16_t *far_end, spx_int16_t *out)
+{
+   int i,j;
+   int N,M;
+   spx_word32_t Syy,See,Sxx,Sdd, Sff;
+#ifdef TWO_PATH
+   spx_word32_t Dbf;
+   int update_foreground;
+#endif
+   spx_word32_t Sey;
+   spx_word16_t ss, ss_1;
+   spx_float_t Pey = FLOAT_ONE, Pyy=FLOAT_ONE;
+   spx_float_t alpha, alpha_1;
+   spx_word16_t RER;
+   spx_word32_t tmp32;
+   
+   N = st->window_size;
+   M = st->M;
+   st->cancel_count++;
+#ifdef FIXED_POINT
+   ss=DIV32_16(11469,M);
+   ss_1 = SUB16(32767,ss);
+#else
+   ss=.35/M;
+   ss_1 = 1-ss;
+#endif
+
+   /* Apply a notch filter to make sure DC doesn't end up causing problems */
+   filter_dc_notch16(in, st->notch_radius, st->input, st->frame_size, st->notch_mem);
+   /* Copy input data to buffer and apply pre-emphasis */
+   for (i=0;i<st->frame_size;i++)
+   {
+      spx_word32_t tmp32;
+      tmp32 = SUB32(EXTEND32(far_end[i]), EXTEND32(MULT16_16_P15(st->preemph, st->memX)));
+#ifdef FIXED_POINT
+      /* If saturation occurs here, we need to freeze adaptation for M+1 frames (not just one) */
+      if (tmp32 > 32767)
+      {
+         tmp32 = 32767;
+         st->saturated = M+1;
+      }
+      if (tmp32 < -32767)
+      {
+         tmp32 = -32767;
+         st->saturated = M+1;
+      }      
+#endif
+      st->x[i+st->frame_size] = EXTRACT16(tmp32);
+      st->memX = far_end[i];
+      
+      tmp32 = SUB32(EXTEND32(st->input[i]), EXTEND32(MULT16_16_P15(st->preemph, st->memD)));
+#ifdef FIXED_POINT
+      if (tmp32 > 32767)
+      {
+         tmp32 = 32767;
+         if (st->saturated == 0)
+            st->saturated = 1;
+      }      
+      if (tmp32 < -32767)
+      {
+         tmp32 = -32767;
+         if (st->saturated == 0)
+            st->saturated = 1;
+      }
+#endif
+      st->memD = st->input[i];
+      st->input[i] = tmp32;
+   }
+
+   /* Shift memory: this could be optimized eventually*/
+   for (j=M-1;j>=0;j--)
+   {
+      for (i=0;i<N;i++)
+         st->X[(j+1)*N+i] = st->X[j*N+i];
+   }
+
+   /* Convert x (far end) to frequency domain */
+   spx_fft(st->fft_table, st->x, &st->X[0]);
+   for (i=0;i<N;i++)
+      st->last_y[i] = st->x[i];
+   Sxx = mdf_inner_prod(st->x+st->frame_size, st->x+st->frame_size, st->frame_size);
+   for (i=0;i<st->frame_size;i++)
+      st->x[i] = st->x[i+st->frame_size];
+   /* From here on, the top part of x is used as scratch space */
+   
+#ifdef TWO_PATH
+   /* Compute foreground filter */
+   spectral_mul_accum16(st->X, st->foreground, st->Y, N, M);   
+   spx_ifft(st->fft_table, st->Y, st->e);
+   for (i=0;i<st->frame_size;i++)
+      st->e[i] = SUB16(st->input[i], st->e[i+st->frame_size]);
+   Sff = mdf_inner_prod(st->e, st->e, st->frame_size);
+#endif
+   
+   /* Adjust proportional adaption rate */
+   mdf_adjust_prop (st->W, N, M, st->prop);
+   /* Compute weight gradient */
+   if (st->saturated == 0)
+   {
+      for (j=M-1;j>=0;j--)
+      {
+         weighted_spectral_mul_conj(st->power_1, FLOAT_SHL(PSEUDOFLOAT(st->prop[j]),-15), &st->X[(j+1)*N], st->E, st->PHI, N);
+         for (i=0;i<N;i++)
+            st->W[j*N+i] = ADD32(st->W[j*N+i], st->PHI[i]);
+         
+      }
+   } else {
+      st->saturated--;
+   }
+   
+   /* Update weight to prevent circular convolution (MDF / AUMDF) */
+   for (j=0;j<M;j++)
+   {
+      /* This is a variant of the Alternatively Updated MDF (AUMDF) */
+      /* Remove the "if" to make this an MDF filter */
+      if (j==0 || st->cancel_count%(M-1) == j-1)
+      {
+#ifdef FIXED_POINT
+         for (i=0;i<N;i++)
+            st->wtmp2[i] = EXTRACT16(PSHR32(st->W[j*N+i],NORMALIZE_SCALEDOWN+16));
+         spx_ifft(st->fft_table, st->wtmp2, st->wtmp);
+         for (i=0;i<st->frame_size;i++)
+         {
+            st->wtmp[i]=0;
+         }
+         for (i=st->frame_size;i<N;i++)
+         {
+            st->wtmp[i]=SHL16(st->wtmp[i],NORMALIZE_SCALEUP);
+         }
+         spx_fft(st->fft_table, st->wtmp, st->wtmp2);
+         /* The "-1" in the shift is a sort of kludge that trades less efficient update speed for decrease noise */
+         for (i=0;i<N;i++)
+            st->W[j*N+i] -= SHL32(EXTEND32(st->wtmp2[i]),16+NORMALIZE_SCALEDOWN-NORMALIZE_SCALEUP-1);
+#else
+         spx_ifft(st->fft_table, &st->W[j*N], st->wtmp);
+         for (i=st->frame_size;i<N;i++)
+         {
+            st->wtmp[i]=0;
+         }
+         spx_fft(st->fft_table, st->wtmp, &st->W[j*N]);
+#endif
+      }
+   }
+
+   /* Compute filter response Y */
+   spectral_mul_accum(st->X, st->W, st->Y, N, M);
+   spx_ifft(st->fft_table, st->Y, st->y);
+
+#ifdef TWO_PATH
+   /* Difference in response, this is used to estimate the variance of our residual power estimate */
+   for (i=0;i<st->frame_size;i++)
+      st->e[i] = SUB16(st->e[i+st->frame_size], st->y[i+st->frame_size]);
+   Dbf = 10+mdf_inner_prod(st->e, st->e, st->frame_size);
+#endif
+
+   for (i=0;i<st->frame_size;i++)
+      st->e[i] = SUB16(st->input[i], st->y[i+st->frame_size]);
+   See = mdf_inner_prod(st->e, st->e, st->frame_size);
+#ifndef TWO_PATH
+   Sff = See;
+#endif
+
+#ifdef TWO_PATH
+   /* Logic for updating the foreground filter */
+   
+   /* For two time windows, compute the mean of the energy difference, as well as the variance */
+   st->Davg1 = ADD32(MULT16_32_Q15(QCONST16(.6f,15),st->Davg1), MULT16_32_Q15(QCONST16(.4f,15),SUB32(Sff,See)));
+   st->Davg2 = ADD32(MULT16_32_Q15(QCONST16(.85f,15),st->Davg2), MULT16_32_Q15(QCONST16(.15f,15),SUB32(Sff,See)));
+   st->Dvar1 = FLOAT_ADD(FLOAT_MULT(VAR1_SMOOTH, st->Dvar1), FLOAT_MUL32U(MULT16_32_Q15(QCONST16(.4f,15),Sff), MULT16_32_Q15(QCONST16(.4f,15),Dbf)));
+   st->Dvar2 = FLOAT_ADD(FLOAT_MULT(VAR2_SMOOTH, st->Dvar2), FLOAT_MUL32U(MULT16_32_Q15(QCONST16(.15f,15),Sff), MULT16_32_Q15(QCONST16(.15f,15),Dbf)));
+   
+   /* Equivalent float code:
+   st->Davg1 = .6*st->Davg1 + .4*(Sff-See);
+   st->Davg2 = .85*st->Davg2 + .15*(Sff-See);
+   st->Dvar1 = .36*st->Dvar1 + .16*Sff*Dbf;
+   st->Dvar2 = .7225*st->Dvar2 + .0225*Sff*Dbf;
+   */
+   
+   update_foreground = 0;
+   /* Check if we have a statistically significant reduction in the residual echo */
+   /* Note that this is *not* Gaussian, so we need to be careful about the longer tail */
+   if (FLOAT_GT(FLOAT_MUL32U(SUB32(Sff,See),ABS32(SUB32(Sff,See))), FLOAT_MUL32U(Sff,Dbf)))
+      update_foreground = 1;
+   else if (FLOAT_GT(FLOAT_MUL32U(st->Davg1, ABS32(st->Davg1)), FLOAT_MULT(VAR1_UPDATE,(st->Dvar1))))
+      update_foreground = 1;
+   else if (FLOAT_GT(FLOAT_MUL32U(st->Davg2, ABS32(st->Davg2)), FLOAT_MULT(VAR2_UPDATE,(st->Dvar2))))
+      update_foreground = 1;
+   
+   /* Do we update? */
+   if (update_foreground)
+   {
+      st->Davg1 = st->Davg2 = 0;
+      st->Dvar1 = st->Dvar2 = FLOAT_ZERO;
+      /* Copy background filter to foreground filter */
+      for (i=0;i<N*M;i++)
+         st->foreground[i] = EXTRACT16(PSHR32(st->W[i],16));
+      /* Apply a smooth transition so as to not introduce blocking artifacts */
+      for (i=0;i<st->frame_size;i++)
+         st->e[i+st->frame_size] = MULT16_16_Q15(st->window[i+st->frame_size],st->e[i+st->frame_size]) + MULT16_16_Q15(st->window[i],st->y[i+st->frame_size]);
+   } else {
+      int reset_background=0;
+      /* Otherwise, check if the background filter is significantly worse */
+      if (FLOAT_GT(FLOAT_MUL32U(NEG32(SUB32(Sff,See)),ABS32(SUB32(Sff,See))), FLOAT_MULT(VAR_BACKTRACK,FLOAT_MUL32U(Sff,Dbf))))
+         reset_background = 1;
+      if (FLOAT_GT(FLOAT_MUL32U(NEG32(st->Davg1), ABS32(st->Davg1)), FLOAT_MULT(VAR_BACKTRACK,st->Dvar1)))
+         reset_background = 1;
+      if (FLOAT_GT(FLOAT_MUL32U(NEG32(st->Davg2), ABS32(st->Davg2)), FLOAT_MULT(VAR_BACKTRACK,st->Dvar2)))
+         reset_background = 1;
+      if (reset_background)
+      {
+         /* Copy foreground filter to background filter */
+         for (i=0;i<N*M;i++)
+            st->W[i] = SHL32(EXTEND32(st->foreground[i]),16);
+         /* We also need to copy the output so as to get correct adaptation */
+         for (i=0;i<st->frame_size;i++)
+            st->y[i+st->frame_size] = st->e[i+st->frame_size];
+         for (i=0;i<st->frame_size;i++)
+            st->e[i] = SUB16(st->input[i], st->y[i+st->frame_size]);
+         See = Sff;
+         st->Davg1 = st->Davg2 = 0;
+         st->Dvar1 = st->Dvar2 = FLOAT_ZERO;
+      }
+   }
+#endif
+
+   /* Compute error signal (for the output with de-emphasis) */ 
+   for (i=0;i<st->frame_size;i++)
+   {
+      spx_word32_t tmp_out;
+#ifdef TWO_PATH
+      tmp_out = SUB32(EXTEND32(st->input[i]), EXTEND32(st->e[i+st->frame_size]));
+#else
+      tmp_out = SUB32(EXTEND32(st->input[i]), EXTEND32(st->y[i+st->frame_size]));
+#endif
+      /* Saturation */
+      if (tmp_out>32767)
+         tmp_out = 32767;
+      else if (tmp_out<-32768)
+         tmp_out = -32768;
+      tmp_out = ADD32(tmp_out, EXTEND32(MULT16_16_P15(st->preemph, st->memE)));
+      /* This is an arbitrary test for saturation in the microphone signal */
+      if (in[i] <= -32000 || in[i] >= 32000)
+      {
+         tmp_out = 0;
+         if (st->saturated == 0)
+            st->saturated = 1;
+      }
+      out[i] = (spx_int16_t)tmp_out;
+      st->memE = tmp_out;
+   }
+   
+#ifdef DUMP_ECHO_CANCEL_DATA
+   dump_audio(in, far_end, out, st->frame_size);
+#endif
+   
+   /* Compute error signal (filter update version) */ 
+   for (i=0;i<st->frame_size;i++)
+   {
+      st->e[i+st->frame_size] = st->e[i];
+      st->e[i] = 0;
+   }
+
+   /* Compute a bunch of correlations */
+   Sey = mdf_inner_prod(st->e+st->frame_size, st->y+st->frame_size, st->frame_size);
+   Syy = mdf_inner_prod(st->y+st->frame_size, st->y+st->frame_size, st->frame_size);
+   Sdd = mdf_inner_prod(st->input, st->input, st->frame_size);
+   
+   /*printf ("%f %f %f %f\n", Sff, See, Syy, Sdd, st->update_cond);*/
+   
+   /* Do some sanity check */
+   if (!(Syy>=0 && Sxx>=0 && See >= 0)
+#ifndef FIXED_POINT
+       || !(Sff < N*1e9 && Syy < N*1e9 && Sxx < N*1e9)
+#endif
+      )
+   {
+      /* Things have gone really bad */
+      st->screwed_up += 50;
+      for (i=0;i<st->frame_size;i++)
+         out[i] = 0;
+   } else if (SHR32(Sff, 2) > ADD32(Sdd, SHR32(MULT16_16(N, 10000),6)))
+   {
+      /* AEC seems to add lots of echo instead of removing it, let's see if it will improve */
+      st->screwed_up++;
+   } else {
+      /* Everything's fine */
+      st->screwed_up=0;
+   }
+   if (st->screwed_up>=50)
+   {
+      speex_warning("The echo canceller started acting funny and got slapped (reset). It swears it will behave now.");
+      speex_echo_state_reset(st);
+      return;
+   }
+
+   /* Add a small noise floor to make sure not to have problems when dividing */
+   See = MAX32(See, SHR32(MULT16_16(N, 100),6));
+
+   /* Convert error to frequency domain */
+   spx_fft(st->fft_table, st->e, st->E);
+   for (i=0;i<st->frame_size;i++)
+      st->y[i] = 0;
+   spx_fft(st->fft_table, st->y, st->Y);
+
+   /* Compute power spectrum of far end (X), error (E) and filter response (Y) */
+   power_spectrum(st->E, st->Rf, N);
+   power_spectrum(st->Y, st->Yf, N);
+   power_spectrum(st->X, st->Xf, N);
+   
+   /* Smooth far end energy estimate over time */
+   for (j=0;j<=st->frame_size;j++)
+      st->power[j] = MULT16_32_Q15(ss_1,st->power[j]) + 1 + MULT16_32_Q15(ss,st->Xf[j]);
+   
+   /* Enable this to compute the power based only on the tail (would need to compute more 
+      efficiently to make this really useful */
+   if (0)
+   {
+      float scale2 = .5f/M;
+      for (j=0;j<=st->frame_size;j++)
+         st->power[j] = 100;
+      for (i=0;i<M;i++)
+      {
+         power_spectrum(&st->X[i*N], st->Xf, N);
+         for (j=0;j<=st->frame_size;j++)
+            st->power[j] += scale2*st->Xf[j];
+      }
+   }
+
+   /* Compute filtered spectra and (cross-)correlations */
+   for (j=st->frame_size;j>=0;j--)
+   {
+      spx_float_t Eh, Yh;
+      Eh = PSEUDOFLOAT(st->Rf[j] - st->Eh[j]);
+      Yh = PSEUDOFLOAT(st->Yf[j] - st->Yh[j]);
+      Pey = FLOAT_ADD(Pey,FLOAT_MULT(Eh,Yh));
+      Pyy = FLOAT_ADD(Pyy,FLOAT_MULT(Yh,Yh));
+#ifdef FIXED_POINT
+      st->Eh[j] = MAC16_32_Q15(MULT16_32_Q15(SUB16(32767,st->spec_average),st->Eh[j]), st->spec_average, st->Rf[j]);
+      st->Yh[j] = MAC16_32_Q15(MULT16_32_Q15(SUB16(32767,st->spec_average),st->Yh[j]), st->spec_average, st->Yf[j]);
+#else
+      st->Eh[j] = (1-st->spec_average)*st->Eh[j] + st->spec_average*st->Rf[j];
+      st->Yh[j] = (1-st->spec_average)*st->Yh[j] + st->spec_average*st->Yf[j];
+#endif
+   }
+   
+   Pyy = FLOAT_SQRT(Pyy);
+   Pey = FLOAT_DIVU(Pey,Pyy);
+
+   /* Compute correlation updatete rate */
+   tmp32 = MULT16_32_Q15(st->beta0,Syy);
+   if (tmp32 > MULT16_32_Q15(st->beta_max,See))
+      tmp32 = MULT16_32_Q15(st->beta_max,See);
+   alpha = FLOAT_DIV32(tmp32, See);
+   alpha_1 = FLOAT_SUB(FLOAT_ONE, alpha);
+   /* Update correlations (recursive average) */
+   st->Pey = FLOAT_ADD(FLOAT_MULT(alpha_1,st->Pey) , FLOAT_MULT(alpha,Pey));
+   st->Pyy = FLOAT_ADD(FLOAT_MULT(alpha_1,st->Pyy) , FLOAT_MULT(alpha,Pyy));
+   if (FLOAT_LT(st->Pyy, FLOAT_ONE))
+      st->Pyy = FLOAT_ONE;
+   /* We don't really hope to get better than 33 dB (MIN_LEAK-3dB) attenuation anyway */
+   if (FLOAT_LT(st->Pey, FLOAT_MULT(MIN_LEAK,st->Pyy)))
+      st->Pey = FLOAT_MULT(MIN_LEAK,st->Pyy);
+   if (FLOAT_GT(st->Pey, st->Pyy))
+      st->Pey = st->Pyy;
+   /* leak_estimate is the linear regression result */
+   st->leak_estimate = FLOAT_EXTRACT16(FLOAT_SHL(FLOAT_DIVU(st->Pey, st->Pyy),14));
+   /* This looks like a stupid bug, but it's right (because we convert from Q14 to Q15) */
+   if (st->leak_estimate > 16383)
+      st->leak_estimate = 32767;
+   else
+      st->leak_estimate = SHL16(st->leak_estimate,1);
+   /*printf ("%f\n", st->leak_estimate);*/
+   
+   /* Compute Residual to Error Ratio */
+#ifdef FIXED_POINT
+   tmp32 = MULT16_32_Q15(st->leak_estimate,Syy);
+   tmp32 = ADD32(SHR32(Sxx,13), ADD32(tmp32, SHL32(tmp32,1)));
+   /* Check for y in e (lower bound on RER) */
+   {
+      spx_float_t bound = PSEUDOFLOAT(Sey);
+      bound = FLOAT_DIVU(FLOAT_MULT(bound, bound), PSEUDOFLOAT(ADD32(1,Syy)));
+      if (FLOAT_GT(bound, PSEUDOFLOAT(See)))
+         tmp32 = See;
+      else if (tmp32 < FLOAT_EXTRACT32(bound))
+         tmp32 = FLOAT_EXTRACT32(bound);
+   }
+   if (tmp32 > SHR32(See,1))
+      tmp32 = SHR32(See,1);
+   RER = FLOAT_EXTRACT16(FLOAT_SHL(FLOAT_DIV32(tmp32,See),15));
+#else
+   RER = (.0001*Sxx + 3.*MULT16_32_Q15(st->leak_estimate,Syy)) / See;
+   /* Check for y in e (lower bound on RER) */
+   if (RER < Sey*Sey/(1+See*Syy))
+      RER = Sey*Sey/(1+See*Syy);
+   if (RER > .5)
+      RER = .5;
+#endif
+
+   /* We consider that the filter has had minimal adaptation if the following is true*/
+   if (!st->adapted && st->sum_adapt > SHL32(EXTEND32(M),15) && MULT16_32_Q15(st->leak_estimate,Syy) > MULT16_32_Q15(QCONST16(.03f,15),Syy))
+   {
+      st->adapted = 1;
+   }
+
+   if (st->adapted)
+   {
+      /* Normal learning rate calculation once we're past the minimal adaptation phase */
+      for (i=0;i<=st->frame_size;i++)
+      {
+         spx_word32_t r, e;
+         /* Compute frequency-domain adaptation mask */
+         r = MULT16_32_Q15(st->leak_estimate,SHL32(st->Yf[i],3));
+         e = SHL32(st->Rf[i],3)+1;
+#ifdef FIXED_POINT
+         if (r>SHR32(e,1))
+            r = SHR32(e,1);
+#else
+         if (r>.5*e)
+            r = .5*e;
+#endif
+         r = MULT16_32_Q15(QCONST16(.7,15),r) + MULT16_32_Q15(QCONST16(.3,15),(spx_word32_t)(MULT16_32_Q15(RER,e)));
+         /*st->power_1[i] = adapt_rate*r/(e*(1+st->power[i]));*/
+         st->power_1[i] = FLOAT_SHL(FLOAT_DIV32_FLOAT(r,FLOAT_MUL32U(e,st->power[i]+10)),WEIGHT_SHIFT+16);
+      }
+   } else {
+      /* Temporary adaption rate if filter is not yet adapted enough */
+      spx_word16_t adapt_rate=0;
+
+      if (Sxx > SHR32(MULT16_16(N, 1000),6)) 
+      {
+         tmp32 = MULT16_32_Q15(QCONST16(.25f, 15), Sxx);
+#ifdef FIXED_POINT
+         if (tmp32 > SHR32(See,2))
+            tmp32 = SHR32(See,2);
+#else
+         if (tmp32 > .25*See)
+            tmp32 = .25*See;
+#endif
+         adapt_rate = FLOAT_EXTRACT16(FLOAT_SHL(FLOAT_DIV32(tmp32, See),15));
+      }
+      for (i=0;i<=st->frame_size;i++)
+         st->power_1[i] = FLOAT_SHL(FLOAT_DIV32(EXTEND32(adapt_rate),ADD32(st->power[i],10)),WEIGHT_SHIFT+1);
+
+
+      /* How much have we adapted so far? */
+      st->sum_adapt = ADD32(st->sum_adapt,adapt_rate);
+   }
+
+   /* Save residual echo so it can be used by the nonlinear processor */
+   if (st->adapted)
+   {
+      /* If the filter is adapted, take the filtered echo */
+      for (i=0;i<st->frame_size;i++)
+         st->last_y[i] = st->last_y[st->frame_size+i];
+      for (i=0;i<st->frame_size;i++)
+         st->last_y[st->frame_size+i] = in[i]-out[i];
+   } else {
+      /* If filter isn't adapted yet, all we can do is take the far end signal directly */
+      /* moved earlier: for (i=0;i<N;i++)
+      st->last_y[i] = st->x[i];*/
+   }
+
+}
+
+/* Compute spectrum of estimated echo for use in an echo post-filter */
+void speex_echo_get_residual(SpeexEchoState *st, spx_word32_t *residual_echo, int len)
+{
+   int i;
+   spx_word16_t leak2;
+   int N;
+   
+   N = st->window_size;
+
+   /* Apply hanning window (should pre-compute it)*/
+   for (i=0;i<N;i++)
+      st->y[i] = MULT16_16_Q15(st->window[i],st->last_y[i]);
+      
+   /* Compute power spectrum of the echo */
+   spx_fft(st->fft_table, st->y, st->Y);
+   power_spectrum(st->Y, residual_echo, N);
+      
+#ifdef FIXED_POINT
+   if (st->leak_estimate > 16383)
+      leak2 = 32767;
+   else
+      leak2 = SHL16(st->leak_estimate, 1);
+#else
+   if (st->leak_estimate>.5)
+      leak2 = 1;
+   else
+      leak2 = 2*st->leak_estimate;
+#endif
+   /* Estimate residual echo */
+   for (i=0;i<=st->frame_size;i++)
+      residual_echo[i] = (spx_int32_t)MULT16_32_Q15(leak2,residual_echo[i]);
+   
+}
+
+int speex_echo_ctl(SpeexEchoState *st, int request, void *ptr)
+{
+   switch(request)
+   {
+      
+      case SPEEX_ECHO_GET_FRAME_SIZE:
+         (*(int*)ptr) = st->frame_size;
+         break;
+      case SPEEX_ECHO_SET_SAMPLING_RATE:
+         st->sampling_rate = (*(int*)ptr);
+         st->spec_average = DIV32_16(SHL32(EXTEND32(st->frame_size), 15), st->sampling_rate);
+#ifdef FIXED_POINT
+         st->beta0 = DIV32_16(SHL32(EXTEND32(st->frame_size), 16), st->sampling_rate);
+         st->beta_max = DIV32_16(SHL32(EXTEND32(st->frame_size), 14), st->sampling_rate);
+#else
+         st->beta0 = (2.0f*st->frame_size)/st->sampling_rate;
+         st->beta_max = (.5f*st->frame_size)/st->sampling_rate;
+#endif
+         if (st->sampling_rate<12000)
+            st->notch_radius = QCONST16(.9, 15);
+         else if (st->sampling_rate<24000)
+            st->notch_radius = QCONST16(.982, 15);
+         else
+            st->notch_radius = QCONST16(.992, 15);
+         break;
+      case SPEEX_ECHO_GET_SAMPLING_RATE:
+         (*(int*)ptr) = st->sampling_rate;
+         break;
+      default:
+         speex_warning_int("Unknown speex_echo_ctl request: ", request);
+         return -1;
+   }
+   return 0;
+}