Add copy of opus library in deps/third_party.

opus/celt/pitch.c

+/* Copyright (c) 2007-2008 CSIRO
+   Copyright (c) 2007-2009 Xiph.Org Foundation
+   Written by Jean-Marc Valin */
+/**
+   @file pitch.c
+   @brief Pitch analysis
+ */
+
+/*
+   Redistribution and use in source and binary forms, with or without
+   modification, are permitted provided that the following conditions
+   are met:
+
+   - Redistributions of source code must retain the above copyright
+   notice, this list of conditions and the following disclaimer.
+
+   - Redistributions in binary form must reproduce the above copyright
+   notice, this list of conditions and the following disclaimer in the
+   documentation and/or other materials provided with the distribution.
+
+   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+   ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
+   OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+   EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+   PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+   PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+   LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+   NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+   SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include "pitch.h"
+#include "os_support.h"
+#include "modes.h"
+#include "stack_alloc.h"
+#include "mathops.h"
+#include "celt_lpc.h"
+
+static void find_best_pitch(opus_val32 *xcorr, opus_val16 *y, int len,
+                            int max_pitch, int *best_pitch
+#ifdef FIXED_POINT
+                            , int yshift, opus_val32 maxcorr
+#endif
+                            )
+{
+   int i, j;
+   opus_val32 Syy=1;
+   opus_val16 best_num[2];
+   opus_val32 best_den[2];
+#ifdef FIXED_POINT
+   int xshift;
+
+   xshift = celt_ilog2(maxcorr)-14;
+#endif
+
+   best_num[0] = -1;
+   best_num[1] = -1;
+   best_den[0] = 0;
+   best_den[1] = 0;
+   best_pitch[0] = 0;
+   best_pitch[1] = 1;
+   for (j=0;j<len;j++)
+      Syy = ADD32(Syy, SHR32(MULT16_16(y[j],y[j]), yshift));
+   for (i=0;i<max_pitch;i++)
+   {
+      if (xcorr[i]>0)
+      {
+         opus_val16 num;
+         opus_val32 xcorr16;
+         xcorr16 = EXTRACT16(VSHR32(xcorr[i], xshift));
+#ifndef FIXED_POINT
+         /* Considering the range of xcorr16, this should avoid both underflows
+            and overflows (inf) when squaring xcorr16 */
+         xcorr16 *= 1e-12;
+#endif
+         num = MULT16_16_Q15(xcorr16,xcorr16);
+         if (MULT16_32_Q15(num,best_den[1]) > MULT16_32_Q15(best_num[1],Syy))
+         {
+            if (MULT16_32_Q15(num,best_den[0]) > MULT16_32_Q15(best_num[0],Syy))
+            {
+               best_num[1] = best_num[0];
+               best_den[1] = best_den[0];
+               best_pitch[1] = best_pitch[0];
+               best_num[0] = num;
+               best_den[0] = Syy;
+               best_pitch[0] = i;
+            } else {
+               best_num[1] = num;
+               best_den[1] = Syy;
+               best_pitch[1] = i;
+            }
+         }
+      }
+      Syy += SHR32(MULT16_16(y[i+len],y[i+len]),yshift) - SHR32(MULT16_16(y[i],y[i]),yshift);
+      Syy = MAX32(1, Syy);
+   }
+}
+
+void pitch_downsample(celt_sig * OPUS_RESTRICT x[], opus_val16 * OPUS_RESTRICT x_lp,
+      int len, int C)
+{
+   int i;
+   opus_val32 ac[5];
+   opus_val16 tmp=Q15ONE;
+   opus_val16 lpc[4], mem[4]={0,0,0,0};
+#ifdef FIXED_POINT
+   int shift;
+   opus_val32 maxabs = celt_maxabs32(x[0], len);
+   if (C==2)
+   {
+      opus_val32 maxabs_1 = celt_maxabs32(x[1], len);
+      maxabs = MAX32(maxabs, maxabs_1);
+   }
+   if (maxabs<1)
+      maxabs=1;
+   shift = celt_ilog2(maxabs)-10;
+   if (shift<0)
+      shift=0;
+   if (C==2)
+      shift++;
+#endif
+   for (i=1;i<len>>1;i++)
+      x_lp[i] = SHR32(HALF32(HALF32(x[0][(2*i-1)]+x[0][(2*i+1)])+x[0][2*i]), shift);
+   x_lp[0] = SHR32(HALF32(HALF32(x[0][1])+x[0][0]), shift);
+   if (C==2)
+   {
+      for (i=1;i<len>>1;i++)
+         x_lp[i] += SHR32(HALF32(HALF32(x[1][(2*i-1)]+x[1][(2*i+1)])+x[1][2*i]), shift);
+      x_lp[0] += SHR32(HALF32(HALF32(x[1][1])+x[1][0]), shift);
+   }
+
+   _celt_autocorr(x_lp, ac, NULL, 0,
+                  4, len>>1);
+
+   /* Noise floor -40 dB */
+#ifdef FIXED_POINT
+   ac[0] += SHR32(ac[0],13);
+#else
+   ac[0] *= 1.0001f;
+#endif
+   /* Lag windowing */
+   for (i=1;i<=4;i++)
+   {
+      /*ac[i] *= exp(-.5*(2*M_PI*.002*i)*(2*M_PI*.002*i));*/
+#ifdef FIXED_POINT
+      ac[i] -= MULT16_32_Q15(2*i*i, ac[i]);
+#else
+      ac[i] -= ac[i]*(.008f*i)*(.008f*i);
+#endif
+   }
+
+   _celt_lpc(lpc, ac, 4);
+   for (i=0;i<4;i++)
+   {
+      tmp = MULT16_16_Q15(QCONST16(.9f,15), tmp);
+      lpc[i] = MULT16_16_Q15(lpc[i], tmp);
+   }
+   celt_fir(x_lp, lpc, x_lp, len>>1, 4, mem);
+
+   mem[0]=0;
+   lpc[0]=QCONST16(.8f,12);
+   celt_fir(x_lp, lpc, x_lp, len>>1, 1, mem);
+
+}
+
+void pitch_search(const opus_val16 * OPUS_RESTRICT x_lp, opus_val16 * OPUS_RESTRICT y,
+                  int len, int max_pitch, int *pitch)
+{
+   int i, j;
+   int lag;
+   int best_pitch[2]={0,0};
+   VARDECL(opus_val16, x_lp4);
+   VARDECL(opus_val16, y_lp4);
+   VARDECL(opus_val32, xcorr);
+#ifdef FIXED_POINT
+   opus_val32 maxcorr=1;
+   opus_val16 xmax, ymax;
+   int shift=0;
+#endif
+   int offset;
+
+   SAVE_STACK;
+
+   celt_assert(len>0);
+   celt_assert(max_pitch>0);
+   lag = len+max_pitch;
+
+   ALLOC(x_lp4, len>>2, opus_val16);
+   ALLOC(y_lp4, lag>>2, opus_val16);
+   ALLOC(xcorr, max_pitch>>1, opus_val32);
+
+   /* Downsample by 2 again */
+   for (j=0;j<len>>2;j++)
+      x_lp4[j] = x_lp[2*j];
+   for (j=0;j<lag>>2;j++)
+      y_lp4[j] = y[2*j];
+
+#ifdef FIXED_POINT
+   xmax = celt_maxabs16(x_lp4, len>>2);
+   ymax = celt_maxabs16(y_lp4, lag>>2);
+   shift = celt_ilog2(MAX16(1, MAX16(xmax, ymax)))-11;
+   if (shift>0)
+   {
+      for (j=0;j<len>>2;j++)
+         x_lp4[j] = SHR16(x_lp4[j], shift);
+      for (j=0;j<lag>>2;j++)
+         y_lp4[j] = SHR16(y_lp4[j], shift);
+      /* Use double the shift for a MAC */
+      shift *= 2;
+   } else {
+      shift = 0;
+   }
+#endif
+
+   /* Coarse search with 4x decimation */
+
+   for (i=0;i<max_pitch>>2;i++)
+   {
+      opus_val32 sum = 0;
+      for (j=0;j<len>>2;j++)
+         sum = MAC16_16(sum, x_lp4[j],y_lp4[i+j]);
+      xcorr[i] = MAX32(-1, sum);
+#ifdef FIXED_POINT
+      maxcorr = MAX32(maxcorr, sum);
+#endif
+   }
+   find_best_pitch(xcorr, y_lp4, len>>2, max_pitch>>2, best_pitch
+#ifdef FIXED_POINT
+                   , 0, maxcorr
+#endif
+                   );
+
+   /* Finer search with 2x decimation */
+#ifdef FIXED_POINT
+   maxcorr=1;
+#endif
+   for (i=0;i<max_pitch>>1;i++)
+   {
+      opus_val32 sum=0;
+      xcorr[i] = 0;
+      if (abs(i-2*best_pitch[0])>2 && abs(i-2*best_pitch[1])>2)
+         continue;
+      for (j=0;j<len>>1;j++)
+         sum += SHR32(MULT16_16(x_lp[j],y[i+j]), shift);
+      xcorr[i] = MAX32(-1, sum);
+#ifdef FIXED_POINT
+      maxcorr = MAX32(maxcorr, sum);
+#endif
+   }
+   find_best_pitch(xcorr, y, len>>1, max_pitch>>1, best_pitch
+#ifdef FIXED_POINT
+                   , shift+1, maxcorr
+#endif
+                   );
+
+   /* Refine by pseudo-interpolation */
+   if (best_pitch[0]>0 && best_pitch[0]<(max_pitch>>1)-1)
+   {
+      opus_val32 a, b, c;
+      a = xcorr[best_pitch[0]-1];
+      b = xcorr[best_pitch[0]];
+      c = xcorr[best_pitch[0]+1];
+      if ((c-a) > MULT16_32_Q15(QCONST16(.7f,15),b-a))
+         offset = 1;
+      else if ((a-c) > MULT16_32_Q15(QCONST16(.7f,15),b-c))
+         offset = -1;
+      else
+         offset = 0;
+   } else {
+      offset = 0;
+   }
+   *pitch = 2*best_pitch[0]-offset;
+
+   RESTORE_STACK;
+}
+
+static const int second_check[16] = {0, 0, 3, 2, 3, 2, 5, 2, 3, 2, 3, 2, 5, 2, 3, 2};
+opus_val16 remove_doubling(opus_val16 *x, int maxperiod, int minperiod,
+      int N, int *T0_, int prev_period, opus_val16 prev_gain)
+{
+   int k, i, T, T0;
+   opus_val16 g, g0;
+   opus_val16 pg;
+   opus_val32 xy,xx,yy;
+   opus_val32 xcorr[3];
+   opus_val32 best_xy, best_yy;
+   int offset;
+   int minperiod0;
+
+   minperiod0 = minperiod;
+   maxperiod /= 2;
+   minperiod /= 2;
+   *T0_ /= 2;
+   prev_period /= 2;
+   N /= 2;
+   x += maxperiod;
+   if (*T0_>=maxperiod)
+      *T0_=maxperiod-1;
+
+   T = T0 = *T0_;
+   xx=xy=yy=0;
+   for (i=0;i<N;i++)
+   {
+      xy = MAC16_16(xy, x[i], x[i-T0]);
+      xx = MAC16_16(xx, x[i], x[i]);
+      yy = MAC16_16(yy, x[i-T0],x[i-T0]);
+   }
+   best_xy = xy;
+   best_yy = yy;
+#ifdef FIXED_POINT
+      {
+         opus_val32 x2y2;
+         int sh, t;
+         x2y2 = 1+HALF32(MULT32_32_Q31(xx,yy));
+         sh = celt_ilog2(x2y2)>>1;
+         t = VSHR32(x2y2, 2*(sh-7));
+         g = g0 = VSHR32(MULT16_32_Q15(celt_rsqrt_norm(t), xy),sh+1);
+      }
+#else
+      g = g0 = xy/celt_sqrt(1+xx*yy);
+#endif
+   /* Look for any pitch at T/k */
+   for (k=2;k<=15;k++)
+   {
+      int T1, T1b;
+      opus_val16 g1;
+      opus_val16 cont=0;
+      T1 = (2*T0+k)/(2*k);
+      if (T1 < minperiod)
+         break;
+      /* Look for another strong correlation at T1b */
+      if (k==2)
+      {
+         if (T1+T0>maxperiod)
+            T1b = T0;
+         else
+            T1b = T0+T1;
+      } else
+      {
+         T1b = (2*second_check[k]*T0+k)/(2*k);
+      }
+      xy=yy=0;
+      for (i=0;i<N;i++)
+      {
+         xy = MAC16_16(xy, x[i], x[i-T1]);
+         yy = MAC16_16(yy, x[i-T1], x[i-T1]);
+
+         xy = MAC16_16(xy, x[i], x[i-T1b]);
+         yy = MAC16_16(yy, x[i-T1b], x[i-T1b]);
+      }
+#ifdef FIXED_POINT
+      {
+         opus_val32 x2y2;
+         int sh, t;
+         x2y2 = 1+MULT32_32_Q31(xx,yy);
+         sh = celt_ilog2(x2y2)>>1;
+         t = VSHR32(x2y2, 2*(sh-7));
+         g1 = VSHR32(MULT16_32_Q15(celt_rsqrt_norm(t), xy),sh+1);
+      }
+#else
+      g1 = xy/celt_sqrt(1+2.f*xx*1.f*yy);
+#endif
+      if (abs(T1-prev_period)<=1)
+         cont = prev_gain;
+      else if (abs(T1-prev_period)<=2 && 5*k*k < T0)
+         cont = HALF32(prev_gain);
+      else
+         cont = 0;
+      if (g1 > QCONST16(.3f,15) + MULT16_16_Q15(QCONST16(.4f,15),g0)-cont)
+      {
+         best_xy = xy;
+         best_yy = yy;
+         T = T1;
+         g = g1;
+      }
+   }
+   best_xy = MAX32(0, best_xy);
+   if (best_yy <= best_xy)
+      pg = Q15ONE;
+   else
+      pg = SHR32(frac_div32(best_xy,best_yy+1),16);
+
+   for (k=0;k<3;k++)
+   {
+      int T1 = T+k-1;
+      xy = 0;
+      for (i=0;i<N;i++)
+         xy = MAC16_16(xy, x[i], x[i-T1]);
+      xcorr[k] = xy;
+   }
+   if ((xcorr[2]-xcorr[0]) > MULT16_32_Q15(QCONST16(.7f,15),xcorr[1]-xcorr[0]))
+      offset = 1;
+   else if ((xcorr[0]-xcorr[2]) > MULT16_32_Q15(QCONST16(.7f,15),xcorr[1]-xcorr[2]))
+      offset = -1;
+   else
+      offset = 0;
+   if (pg > g)
+      pg = g;
+   *T0_ = 2*T+offset;
+
+   if (*T0_<minperiod0)
+      *T0_=minperiod0;
+   return pg;
+}