blob: ac8511ecc288ed27bfc204cd5abf30b87386e872 [file] [log] [blame]
/*
* Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#include "webrtc/modules/audio_coding/codecs/isac/fix/source/pitch_estimator.h"
#include "webrtc/common_audio/signal_processing/include/signal_processing_library.h"
#include "webrtc/rtc_base/compile_assert_c.h"
/* log2[0.2, 0.5, 0.98] in Q8 */
static const int16_t kLogLagWinQ8[3] = {
-594, -256, -7
};
/* [1 -0.75 0.25] in Q12 */
static const int16_t kACoefQ12[3] = {
4096, -3072, 1024
};
int32_t WebRtcIsacfix_Log2Q8(uint32_t x) {
int32_t zeros;
int16_t frac;
zeros=WebRtcSpl_NormU32(x);
frac = (int16_t)(((x << zeros) & 0x7FFFFFFF) >> 23);
/* log2(magn(i)) */
return ((31 - zeros) << 8) + frac;
}
static __inline int16_t Exp2Q10(int16_t x) { // Both in and out in Q10
int16_t tmp16_1, tmp16_2;
tmp16_2=(int16_t)(0x0400|(x&0x03FF));
tmp16_1 = -(x >> 10);
if(tmp16_1>0)
return tmp16_2 >> tmp16_1;
else
return tmp16_2 << -tmp16_1;
}
/* 1D parabolic interpolation . All input and output values are in Q8 */
static __inline void Intrp1DQ8(int32_t *x, int32_t *fx, int32_t *y, int32_t *fy) {
int16_t sign1=1, sign2=1;
int32_t r32, q32, t32, nom32, den32;
int16_t t16, tmp16, tmp16_1;
if ((fx[0]>0) && (fx[2]>0)) {
r32=fx[1]-fx[2];
q32=fx[0]-fx[1];
nom32=q32+r32;
den32 = (q32 - r32) * 2;
if (nom32<0)
sign1=-1;
if (den32<0)
sign2=-1;
/* t = (q32+r32)/(2*(q32-r32)) = (fx[0]-fx[1] + fx[1]-fx[2])/(2 * fx[0]-fx[1] - (fx[1]-fx[2]))*/
/* (Signs are removed because WebRtcSpl_DivResultInQ31 can't handle negative numbers) */
/* t in Q31, without signs */
t32 = WebRtcSpl_DivResultInQ31(nom32 * sign1, den32 * sign2);
t16 = (int16_t)(t32 >> 23); /* Q8 */
t16=t16*sign1*sign2; /* t in Q8 with signs */
*y = x[0]+t16; /* Q8 */
// *y = x[1]+t16; /* Q8 */
/* The following code calculates fy in three steps */
/* fy = 0.5 * t * (t-1) * fx[0] + (1-t*t) * fx[1] + 0.5 * t * (t+1) * fx[2]; */
/* Part I: 0.5 * t * (t-1) * fx[0] */
tmp16_1 = (int16_t)(t16 * t16); /* Q8*Q8=Q16 */
tmp16_1 >>= 2; /* Q16>>2 = Q14 */
t16 <<= 6; /* Q8<<6 = Q14 */
tmp16 = tmp16_1-t16;
*fy = WEBRTC_SPL_MUL_16_32_RSFT15(tmp16, fx[0]); /* (Q14 * Q8 >>15)/2 = Q8 */
/* Part II: (1-t*t) * fx[1] */
tmp16 = 16384-tmp16_1; /* 1 in Q14 - Q14 */
*fy += WEBRTC_SPL_MUL_16_32_RSFT14(tmp16, fx[1]);/* Q14 * Q8 >> 14 = Q8 */
/* Part III: 0.5 * t * (t+1) * fx[2] */
tmp16 = tmp16_1+t16;
*fy += WEBRTC_SPL_MUL_16_32_RSFT15(tmp16, fx[2]);/* (Q14 * Q8 >>15)/2 = Q8 */
} else {
*y = x[0];
*fy= fx[1];
}
}
static void FindFour32(int32_t *in, int16_t length, int16_t *bestind)
{
int32_t best[4]= {-100, -100, -100, -100};
int16_t k;
for (k=0; k<length; k++) {
if (in[k] > best[3]) {
if (in[k] > best[2]) {
if (in[k] > best[1]) {
if (in[k] > best[0]) { // The Best
best[3] = best[2];
bestind[3] = bestind[2];
best[2] = best[1];
bestind[2] = bestind[1];
best[1] = best[0];
bestind[1] = bestind[0];
best[0] = in[k];
bestind[0] = k;
} else { // 2nd best
best[3] = best[2];
bestind[3] = bestind[2];
best[2] = best[1];
bestind[2] = bestind[1];
best[1] = in[k];
bestind[1] = k;
}
} else { // 3rd best
best[3] = best[2];
bestind[3] = bestind[2];
best[2] = in[k];
bestind[2] = k;
}
} else { // 4th best
best[3] = in[k];
bestind[3] = k;
}
}
}
}
extern void WebRtcIsacfix_PCorr2Q32(const int16_t *in, int32_t *logcorQ8);
void WebRtcIsacfix_InitialPitch(const int16_t *in, /* Q0 */
PitchAnalysisStruct *State,
int16_t *lagsQ7 /* Q7 */
)
{
int16_t buf_dec16[PITCH_CORR_LEN2+PITCH_CORR_STEP2+PITCH_MAX_LAG/2+2];
int32_t *crrvecQ8_1,*crrvecQ8_2;
int32_t cv1q[PITCH_LAG_SPAN2+2],cv2q[PITCH_LAG_SPAN2+2], peakvq[PITCH_LAG_SPAN2+2];
int k;
int16_t peaks_indq;
int16_t peakiq[PITCH_LAG_SPAN2];
int32_t corr;
int32_t corr32, corr_max32, corr_max_o32;
int16_t npkq;
int16_t best4q[4]={0,0,0,0};
int32_t xq[3],yq[1],fyq[1];
int32_t *fxq;
int32_t best_lag1q, best_lag2q;
int32_t tmp32a,tmp32b,lag32,ratq;
int16_t start;
int16_t oldgQ12, tmp16a, tmp16b, gain_bias16,tmp16c, tmp16d, bias16;
int32_t tmp32c,tmp32d, tmp32e;
int16_t old_lagQ;
int32_t old_lagQ8;
int32_t lagsQ8[4];
old_lagQ = State->PFstr_wght.oldlagQ7; // Q7
old_lagQ8 = old_lagQ << 1; // Q8
oldgQ12= State->PFstr_wght.oldgainQ12;
crrvecQ8_1=&cv1q[1];
crrvecQ8_2=&cv2q[1];
/* copy old values from state buffer */
memcpy(buf_dec16, State->dec_buffer16, sizeof(State->dec_buffer16));
/* decimation; put result after the old values */
WebRtcIsacfix_DecimateAllpass32(in, State->decimator_state32, PITCH_FRAME_LEN,
&buf_dec16[PITCH_CORR_LEN2+PITCH_CORR_STEP2+PITCH_MAX_LAG/2-PITCH_FRAME_LEN/2+2]);
/* low-pass filtering */
start= PITCH_CORR_LEN2+PITCH_CORR_STEP2+PITCH_MAX_LAG/2-PITCH_FRAME_LEN/2+2;
WebRtcSpl_FilterARFastQ12(&buf_dec16[start],&buf_dec16[start],(int16_t*)kACoefQ12,3, PITCH_FRAME_LEN/2);
/* copy end part back into state buffer */
for (k = 0; k < (PITCH_CORR_LEN2+PITCH_CORR_STEP2+PITCH_MAX_LAG/2-PITCH_FRAME_LEN/2+2); k++)
State->dec_buffer16[k] = buf_dec16[k+PITCH_FRAME_LEN/2];
/* compute correlation for first and second half of the frame */
WebRtcIsacfix_PCorr2Q32(buf_dec16, crrvecQ8_1);
WebRtcIsacfix_PCorr2Q32(buf_dec16 + PITCH_CORR_STEP2, crrvecQ8_2);
/* bias towards pitch lag of previous frame */
tmp32a = WebRtcIsacfix_Log2Q8((uint32_t) old_lagQ8) - 2304;
// log2(0.5*oldlag) in Q8
tmp32b = oldgQ12 * oldgQ12 >> 10; // Q12 & * 4.0;
gain_bias16 = (int16_t) tmp32b; //Q12
if (gain_bias16 > 3276) gain_bias16 = 3276; // 0.8 in Q12
for (k = 0; k < PITCH_LAG_SPAN2; k++)
{
if (crrvecQ8_1[k]>0) {
tmp32b = WebRtcIsacfix_Log2Q8((uint32_t) (k + (PITCH_MIN_LAG/2-2)));
tmp16a = (int16_t) (tmp32b - tmp32a); // Q8 & fabs(ratio)<4
tmp32c = tmp16a * tmp16a >> 6; // Q10
tmp16b = (int16_t) tmp32c; // Q10 & <8
tmp32d = tmp16b * 177 >> 8; // mult with ln2 in Q8
tmp16c = (int16_t) tmp32d; // Q10 & <4
tmp16d = Exp2Q10((int16_t) -tmp16c); //Q10
tmp32c = gain_bias16 * tmp16d >> 13; // Q10 & * 0.5
bias16 = (int16_t) (1024 + tmp32c); // Q10
tmp32b = WebRtcIsacfix_Log2Q8((uint32_t)bias16) - 2560;
// Q10 in -> Q8 out with 10*2^8 offset
crrvecQ8_1[k] += tmp32b ; // -10*2^8 offset
}
}
/* taper correlation functions */
for (k = 0; k < 3; k++) {
crrvecQ8_1[k] += kLogLagWinQ8[k];
crrvecQ8_2[k] += kLogLagWinQ8[k];
crrvecQ8_1[PITCH_LAG_SPAN2-1-k] += kLogLagWinQ8[k];
crrvecQ8_2[PITCH_LAG_SPAN2-1-k] += kLogLagWinQ8[k];
}
/* Make zeropadded corr vectors */
cv1q[0]=0;
cv2q[0]=0;
cv1q[PITCH_LAG_SPAN2+1]=0;
cv2q[PITCH_LAG_SPAN2+1]=0;
corr_max32 = 0;
for (k = 1; k <= PITCH_LAG_SPAN2; k++)
{
corr32=crrvecQ8_1[k-1];
if (corr32 > corr_max32)
corr_max32 = corr32;
corr32=crrvecQ8_2[k-1];
corr32 += -4; // Compensate for later (log2(0.99))
if (corr32 > corr_max32)
corr_max32 = corr32;
}
/* threshold value to qualify as a peak */
// corr_max32 += -726; // log(0.14)/log(2.0) in Q8
corr_max32 += -1000; // log(0.14)/log(2.0) in Q8
corr_max_o32 = corr_max32;
/* find peaks in corr1 */
peaks_indq = 0;
for (k = 1; k <= PITCH_LAG_SPAN2; k++)
{
corr32=cv1q[k];
if (corr32>corr_max32) { // Disregard small peaks
if ((corr32>=cv1q[k-1]) && (corr32>cv1q[k+1])) { // Peak?
peakvq[peaks_indq] = corr32;
peakiq[peaks_indq++] = k;
}
}
}
/* find highest interpolated peak */
corr_max32=0;
best_lag1q =0;
if (peaks_indq > 0) {
FindFour32(peakvq, (int16_t) peaks_indq, best4q);
npkq = WEBRTC_SPL_MIN(peaks_indq, 4);
for (k=0;k<npkq;k++) {
lag32 = peakiq[best4q[k]];
fxq = &cv1q[peakiq[best4q[k]]-1];
xq[0]= lag32;
xq[0] <<= 8;
Intrp1DQ8(xq, fxq, yq, fyq);
tmp32a= WebRtcIsacfix_Log2Q8((uint32_t) *yq) - 2048; // offset 8*2^8
/* Bias towards short lags */
/* log(pow(0.8, log(2.0 * *y )))/log(2.0) */
tmp32b = (int16_t)tmp32a * -42 >> 8;
tmp32c= tmp32b + 256;
*fyq += tmp32c;
if (*fyq > corr_max32) {
corr_max32 = *fyq;
best_lag1q = *yq;
}
}
tmp32b = (best_lag1q - OFFSET_Q8) * 2;
lagsQ8[0] = tmp32b + PITCH_MIN_LAG_Q8;
lagsQ8[1] = lagsQ8[0];
} else {
lagsQ8[0] = old_lagQ8;
lagsQ8[1] = lagsQ8[0];
}
/* Bias towards constant pitch */
tmp32a = lagsQ8[0] - PITCH_MIN_LAG_Q8;
ratq = (tmp32a >> 1) + OFFSET_Q8;
for (k = 1; k <= PITCH_LAG_SPAN2; k++)
{
tmp32a = k << 7; // 0.5*k Q8
tmp32b = tmp32a * 2 - ratq; // Q8
tmp32c = (int16_t)tmp32b * (int16_t)tmp32b >> 8; // Q8
tmp32b = tmp32c + (ratq >> 1);
// (k-r)^2 + 0.5 * r Q8
tmp32c = WebRtcIsacfix_Log2Q8((uint32_t)tmp32a) - 2048;
// offset 8*2^8 , log2(0.5*k) Q8
tmp32d = WebRtcIsacfix_Log2Q8((uint32_t)tmp32b) - 2048;
// offset 8*2^8 , log2(0.5*k) Q8
tmp32e = tmp32c - tmp32d;
cv2q[k] += tmp32e >> 1;
}
/* find peaks in corr2 */
corr_max32 = corr_max_o32;
peaks_indq = 0;
for (k = 1; k <= PITCH_LAG_SPAN2; k++)
{
corr=cv2q[k];
if (corr>corr_max32) { // Disregard small peaks
if ((corr>=cv2q[k-1]) && (corr>cv2q[k+1])) { // Peak?
peakvq[peaks_indq] = corr;
peakiq[peaks_indq++] = k;
}
}
}
/* find highest interpolated peak */
corr_max32 = 0;
best_lag2q =0;
if (peaks_indq > 0) {
FindFour32(peakvq, (int16_t) peaks_indq, best4q);
npkq = WEBRTC_SPL_MIN(peaks_indq, 4);
for (k=0;k<npkq;k++) {
lag32 = peakiq[best4q[k]];
fxq = &cv2q[peakiq[best4q[k]]-1];
xq[0]= lag32;
xq[0] <<= 8;
Intrp1DQ8(xq, fxq, yq, fyq);
/* Bias towards short lags */
/* log(pow(0.8, log(2.0f * *y )))/log(2.0f) */
tmp32a= WebRtcIsacfix_Log2Q8((uint32_t) *yq) - 2048; // offset 8*2^8
tmp32b = (int16_t)tmp32a * -82 >> 8;
tmp32c= tmp32b + 256;
*fyq += tmp32c;
if (*fyq > corr_max32) {
corr_max32 = *fyq;
best_lag2q = *yq;
}
}
tmp32b = (best_lag2q - OFFSET_Q8) * 2;
lagsQ8[2] = tmp32b + PITCH_MIN_LAG_Q8;
lagsQ8[3] = lagsQ8[2];
} else {
lagsQ8[2] = lagsQ8[0];
lagsQ8[3] = lagsQ8[0];
}
lagsQ7[0] = (int16_t)(lagsQ8[0] >> 1);
lagsQ7[1] = (int16_t)(lagsQ8[1] >> 1);
lagsQ7[2] = (int16_t)(lagsQ8[2] >> 1);
lagsQ7[3] = (int16_t)(lagsQ8[3] >> 1);
}
void WebRtcIsacfix_PitchAnalysis(const int16_t *inn, /* PITCH_FRAME_LEN samples */
int16_t *outQ0, /* PITCH_FRAME_LEN+QLOOKAHEAD samples */
PitchAnalysisStruct *State,
int16_t *PitchLags_Q7,
int16_t *PitchGains_Q12)
{
int16_t inbufQ0[PITCH_FRAME_LEN + QLOOKAHEAD];
int16_t k;
/* inital pitch estimate */
WebRtcIsacfix_InitialPitch(inn, State, PitchLags_Q7);
/* Calculate gain */
WebRtcIsacfix_PitchFilterGains(inn, &(State->PFstr_wght), PitchLags_Q7, PitchGains_Q12);
/* concatenate previous input's end and current input */
for (k = 0; k < QLOOKAHEAD; k++) {
inbufQ0[k] = State->inbuf[k];
}
for (k = 0; k < PITCH_FRAME_LEN; k++) {
inbufQ0[k+QLOOKAHEAD] = (int16_t) inn[k];
}
/* lookahead pitch filtering for masking analysis */
WebRtcIsacfix_PitchFilter(inbufQ0, outQ0, &(State->PFstr), PitchLags_Q7,PitchGains_Q12, 2);
/* store last part of input */
for (k = 0; k < QLOOKAHEAD; k++) {
State->inbuf[k] = inbufQ0[k + PITCH_FRAME_LEN];
}
}