ref: 294863bbea2d218d58c294b7b9ff60f221494c3d
parent: 5ed24f8155adf59a4134c92383c19dc3cae68033
author: Jean-Marc Valin <[email protected]>
date: Sun Nov 8 17:29:54 EST 2009
Temporal pitch search
--- a/libcelt/celt.c
+++ b/libcelt/celt.c
@@ -104,6 +104,8 @@
celt_sig *in_mem;
celt_sig *out_mem;
+ celt_word16 *pitch_buf;
+ celt_sig xmem;
celt_word16 *oldBandE;
#ifdef EXP_PSY
@@ -185,6 +187,7 @@
st->in_mem = celt_alloc(st->overlap*C*sizeof(celt_sig));
st->out_mem = celt_alloc((MAX_PERIOD+st->overlap)*C*sizeof(celt_sig));
+ st->pitch_buf = celt_alloc((MAX_PERIOD>>1)*sizeof(celt_word16));
st->oldBandE = (celt_word16*)celt_alloc(C*mode->nbEBands*sizeof(celt_word16));
@@ -657,7 +660,8 @@
&& norm_rate < 50;
if (has_pitch)
{- find_spectral_pitch(st->mode, st->mode->fft, &st->mode->psy, in, st->out_mem, st->mode->window, NULL, 2*N-2*N4, MAX_PERIOD-(2*N-2*N4), &pitch_index, C);
+ /*find_spectral_pitch(st->mode, st->mode->fft, &st->mode->psy, in, st->out_mem, st->mode->window, NULL, 2*N-2*N4, MAX_PERIOD-(2*N-2*N4), &pitch_index, C);*/
+ find_temporal_pitch(st->mode, in, st->pitch_buf, 2*N-2*N4, MAX_PERIOD-(2*N-2*N4), &pitch_index, C, &st->xmem);
}
/* Deferred allocation after find_spectral_pitch() to reduce
@@ -667,7 +671,6 @@
ALLOC(pitch_freq, C*N, celt_sig); /**< Interleaved signal MDCTs */
if (has_pitch)
{-
compute_mdcts(st->mode, 0, st->out_mem+pitch_index*C, pitch_freq, C);
has_pitch = compute_pitch_gain(st->mode, freq, pitch_freq, norm_rate, &gain_id, C, &st->gain_prod);
}
@@ -1247,7 +1250,14 @@
if (st->loss_count == 0)
{- find_spectral_pitch(st->mode, st->mode->fft, &st->mode->psy, st->out_mem+MAX_PERIOD-len, st->out_mem, st->mode->window, NULL, len, MAX_PERIOD-len-100, &pitch_index, C);
+ celt_word16 pitch_buf[MAX_PERIOD];
+ celt_word32 tmp=0;
+ /*find_spectral_pitch(st->mode, st->mode->fft, &st->mode->psy, st->out_mem+MAX_PERIOD-len, st->out_mem, st->mode->window, NULL, len, MAX_PERIOD-len-100, &pitch_index, C);*/
+ /* FIXME: Should do a bit of interpolation while decimating */
+ for (i=0;i<MAX_PERIOD;i++)
+ pitch_buf[i] = EXTRACT16(SHR32(st->out_mem[2*i], SIG_SHIFT));
+ find_temporal_pitch(st->mode, st->out_mem+MAX_PERIOD-len, pitch_buf, len, MAX_PERIOD-len-100, &pitch_index, C, &tmp);
+
pitch_index = MAX_PERIOD-len-pitch_index;
st->last_pitch_index = pitch_index;
} else {--- a/libcelt/pitch.c
+++ b/libcelt/pitch.c
@@ -245,5 +245,158 @@
/* The peak in the correlation gives us the pitch */
*pitch = find_max16(Y, max_pitch);
+ /*printf ("%d ", *pitch);*/RESTORE_STACK;
+}
+
+void find_best_pitch(celt_word32 *xcorr, celt_word32 maxcorr, celt_word16 *y, int yshift, int len, int max_pitch, int best_pitch[2])
+{+ int i, j;
+ celt_word32 Syy=1;
+ celt_word16 best_num[2];
+ celt_word32 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 = MAC16_16(Syy, y[j],y[j]);
+ for (i=0;i<max_pitch;i++)
+ {+ float score;
+ if (xcorr[i]>0)
+ {+ celt_word16 num;
+ celt_word32 xcorr16;
+ xcorr16 = EXTRACT16(VSHR32(xcorr[i], xshift));
+ num = MULT16_16_Q15(xcorr16,xcorr16);
+ score = num*1./Syy;
+ 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 find_temporal_pitch(const CELTMode *m, const celt_sig * restrict x, celt_word16 * restrict y, int len, int max_pitch, int *pitch, int _C, celt_sig *xmem)
+{+ int i, j;
+ const int C = CHANNELS(_C);
+ const int lag = MAX_PERIOD;
+ const int N = FRAMESIZE(m);
+ int best_pitch[2]={0};+ celt_word16 x_lp[len>>1];
+ celt_word16 x_lp4[len>>2];
+ celt_word16 y_lp4[lag>>2];
+ celt_word32 xcorr[max_pitch>>1];
+ celt_word32 maxcorr=1;
+ int offset;
+ int shift=0;
+
+ /* Down-sample by two and downmix to mono */
+ for (i=1;i<len>>1;i++)
+ x_lp[i] = SHR32(HALF32(HALF32(x[(2*i-1)*C]+x[(2*i+1)*C])+x[2*i*C]), SIG_SHIFT);
+ x_lp[0] = SHR32(HALF32(HALF32(*xmem+x[C])+x[0]), SIG_SHIFT);
+ *xmem = x[N-C];
+ if (C==2)
+ {+ for (i=1;i<len>>1;i++)
+ x_lp[i] = SHR32(HALF32(HALF32(x[(2*i-1)*C+1]+x[(2*i+1)*C+1])+x[2*i*C+1]), SIG_SHIFT);
+ x_lp[0] += SHR32(HALF32(HALF32(x[C+1])+x[1]), SIG_SHIFT);
+ *xmem += x[N-C+1];
+ }
+
+ /* 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
+ shift = celt_ilog2(MAX16(celt_maxabs16(x_lp4, len>>2), celt_maxabs16(y_lp4, lag>>2)))-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++)
+ {+ celt_word32 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);
+ maxcorr = MAX32(maxcorr, sum);
+ }
+ find_best_pitch(xcorr, maxcorr, y_lp4, 0, len>>2, max_pitch>>2, best_pitch);
+
+ /* Finer search with 2x decimation */
+ maxcorr=1;
+ for (i=0;i<max_pitch>>1;i++)
+ {+ celt_word32 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);
+ maxcorr = MAX32(maxcorr, sum);
+ }
+ find_best_pitch(xcorr, maxcorr, y, shift, len>>1, max_pitch>>1, best_pitch);
+
+ /* Refine by pseudo-interpolation */
+ if (best_pitch[0]>0 && best_pitch[0]<(max_pitch>>1)-1)
+ {+ celt_word32 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;
+
+ CELT_COPY(y, y+(N>>1), (lag-N)>>1);
+ CELT_COPY(y+((lag-N)>>1), x_lp, N>>1);
+
+ /*printf ("%d\n", *pitch);*/}
--- a/libcelt/pitch.h
+++ b/libcelt/pitch.h
@@ -51,4 +51,6 @@
easier to apply psychoacoustic weighting */
void find_spectral_pitch(const CELTMode *m, kiss_fftr_cfg fft, const struct PsyDecay *decay, const celt_sig *x, const celt_sig *y, const celt_word16 *window, celt_word16 * restrict X, int len, int max_pitch, int *pitch, int _C);
+void find_temporal_pitch(const CELTMode *m, const celt_sig * restrict x, celt_word16 * restrict y, int len, int max_pitch, int *pitch, int _C, celt_sig *xmem);
+
#endif