src/third_party/webrtc/modules/audio_coding/codecs/isac/fix/source/pitch_estimator_c.c

   1 /*
   2  *  Copyright (c) 2014 The WebRTC project authors. All Rights Reserved.
   3  *
   4  *  Use of this source code is governed by a BSD-style license
   5  *  that can be found in the LICENSE file in the root of the source
   6  *  tree. An additional intellectual property rights grant can be found
   7  *  in the file PATENTS.  All contributing project authors may
   8  *  be found in the AUTHORS file in the root of the source tree.
   9  */
  10
  11 #include "webrtc/modules/audio_coding/codecs/isac/fix/source/pitch_estimator.h"
  12
  13 #ifdef WEBRTC_ARCH_ARM_NEON
  14 #include <arm_neon.h>
  15 #endif
  16
  17 #include "webrtc/common_audio/signal_processing/include/signal_processing_library.h"
  18 #include "webrtc/system_wrappers/interface/compile_assert_c.h"
  19
  20 extern int32_t WebRtcIsacfix_Log2Q8(uint32_t x);
  21
  22 void WebRtcIsacfix_PCorr2Q32(const int16_t* in, int32_t* logcorQ8) {
  23   int16_t scaling,n,k;
  24   int32_t ysum32,csum32, lys, lcs;
  25   int32_t oneQ8;
  26   const int16_t* x;
  27   const int16_t* inptr;
  28
  29   oneQ8 = WEBRTC_SPL_LSHIFT_W32((int32_t)1, 8);  // 1.00 in Q8
  30
  31   x = in + PITCH_MAX_LAG / 2 + 2;
  32   scaling = WebRtcSpl_GetScalingSquare((int16_t*)in,
  33                                        PITCH_CORR_LEN2,
  34                                        PITCH_CORR_LEN2);
  35   ysum32 = 1;
  36   csum32 = 0;
  37   x = in + PITCH_MAX_LAG / 2 + 2;
  38   for (n = 0; n < PITCH_CORR_LEN2; n++) {
  39     ysum32 += WEBRTC_SPL_MUL_16_16_RSFT((int16_t)in[n],
  40                                         (int16_t)in[n],
  41                                         scaling);  // Q0
  42     csum32 += WEBRTC_SPL_MUL_16_16_RSFT((int16_t)x[n],
  43                                         (int16_t)in[n],
  44                                         scaling);  // Q0
  45   }
  46   logcorQ8 += PITCH_LAG_SPAN2 - 1;
  47   lys = WebRtcIsacfix_Log2Q8((uint32_t)ysum32);    // Q8
  48   lys = WEBRTC_SPL_RSHIFT_W32(lys, 1);  //sqrt(ysum);
  49   if (csum32 > 0) {
  50     lcs = WebRtcIsacfix_Log2Q8((uint32_t)csum32);  // 2log(csum) in Q8
  51     if (lcs > (lys + oneQ8)) {          // csum/sqrt(ysum) > 2 in Q8
  52       *logcorQ8 = lcs - lys;            // log2(csum/sqrt(ysum))
  53     } else {
  54       *logcorQ8 = oneQ8;                // 1.00
  55     }
  56   } else {
  57     *logcorQ8 = 0;
  58   }
  59
  60
  61   for (k = 1; k < PITCH_LAG_SPAN2; k++) {
  62     inptr = &in[k];
  63     ysum32 -= WEBRTC_SPL_MUL_16_16_RSFT((int16_t)in[k - 1],
  64                                         (int16_t)in[k - 1],
  65                                         scaling);
  66     ysum32 += WEBRTC_SPL_MUL_16_16_RSFT((int16_t)in[PITCH_CORR_LEN2 + k - 1],
  67                                         (int16_t)in[PITCH_CORR_LEN2 + k - 1],
  68                                         scaling);
  69 #ifdef WEBRTC_ARCH_ARM_NEON
  70     {
  71       int32_t vbuff[4];
  72       int32x4_t int_32x4_sum = vmovq_n_s32(0);
  73       // Can't shift a Neon register to right with a non-constant shift value.
  74       int32x4_t int_32x4_scale = vdupq_n_s32(-scaling);
  75       // Assert a codition used in loop unrolling at compile-time.
  76       COMPILE_ASSERT(PITCH_CORR_LEN2 %4 == 0);
  77
  78       for (n = 0; n < PITCH_CORR_LEN2; n += 4) {
  79         int16x4_t int_16x4_x = vld1_s16(&x[n]);
  80         int16x4_t int_16x4_in = vld1_s16(&inptr[n]);
  81         int32x4_t int_32x4 = vmull_s16(int_16x4_x, int_16x4_in);
  82         int_32x4 = vshlq_s32(int_32x4, int_32x4_scale);
  83         int_32x4_sum = vaddq_s32(int_32x4_sum, int_32x4);
  84       }
  85
  86       // Use vector store to avoid long stall from data trasferring
  87       // from vector to general register.
  88       vst1q_s32(vbuff, int_32x4_sum);
  89       csum32 = vbuff[0] + vbuff[1];
  90       csum32 += vbuff[2];
  91       csum32 += vbuff[3];
  92     }
  93 #else
  94     csum32 = 0;
  95     if(scaling == 0) {
  96       for (n = 0; n < PITCH_CORR_LEN2; n++) {
  97         csum32 += x[n] * inptr[n];
  98       }
  99     } else {
 100       for (n = 0; n < PITCH_CORR_LEN2; n++) {
 101         csum32 += (x[n] * inptr[n]) >> scaling;
 102       }
 103     }
 104 #endif
 105
 106     logcorQ8--;
 107
 108     lys = WebRtcIsacfix_Log2Q8((uint32_t)ysum32);  // Q8
 109     lys = WEBRTC_SPL_RSHIFT_W32(lys, 1);  //sqrt(ysum);
 110
 111     if (csum32 > 0) {
 112       lcs = WebRtcIsacfix_Log2Q8((uint32_t)csum32);  // 2log(csum) in Q8
 113       if (lcs > (lys + oneQ8)) {          // csum/sqrt(ysum) > 2
 114         *logcorQ8 = lcs - lys;            // log2(csum/sqrt(ysum))
 115       } else {
 116         *logcorQ8 = oneQ8;                // 1.00
 117       }
 118     } else {
 119       *logcorQ8 = 0;
 120     }
 121   }
 122 }