1 /* 2 * Copyright (c) 2011 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 /****************************************************************** 12 13 iLBC Speech Coder ANSI-C Source Code 14 15 WebRtcIlbcfix_GetSyncSeq.c 16 17 ******************************************************************/ 18 19 #include "defines.h" 20 #include "constants.h" 21 #include "refiner.h" 22 #include "nearest_neighbor.h" 23 24 /*----------------------------------------------------------------* 25 * get the pitch-synchronous sample sequence 26 *---------------------------------------------------------------*/ 27 28 void WebRtcIlbcfix_GetSyncSeq( 29 int16_t *idata, /* (i) original data */ 30 int16_t idatal, /* (i) dimension of data */ 31 int16_t centerStartPos, /* (i) where current block starts */ 32 int16_t *period, /* (i) rough-pitch-period array (Q-2) */ 33 int16_t *plocs, /* (i) where periods of period array are taken (Q-2) */ 34 int16_t periodl, /* (i) dimension period array */ 35 int16_t hl, /* (i) 2*hl+1 is the number of sequences */ 36 int16_t *surround /* (i/o) The contribution from this sequence 37 summed with earlier contributions */ 38 ){ 39 int16_t i,centerEndPos,q; 40 /* Stack based */ 41 int16_t lagBlock[2*ENH_HL+1]; 42 int16_t blockStartPos[2*ENH_HL+1]; /* Defines the position to search around (Q2) */ 43 int16_t plocs2[ENH_PLOCSL]; 44 45 centerEndPos=centerStartPos+ENH_BLOCKL-1; 46 47 /* present (find predicted lag from this position) */ 48 49 WebRtcIlbcfix_NearestNeighbor(lagBlock+hl,plocs, 50 (int16_t)WEBRTC_SPL_MUL_16_16(2, (centerStartPos+centerEndPos)), 51 periodl); 52 53 blockStartPos[hl]=(int16_t)WEBRTC_SPL_MUL_16_16(4, centerStartPos); 54 55 /* past (find predicted position and perform a refined 56 search to find the best sequence) */ 57 58 for(q=hl-1;q>=0;q--) { 59 blockStartPos[q]=blockStartPos[q+1]-period[lagBlock[q+1]]; 60 61 WebRtcIlbcfix_NearestNeighbor(lagBlock+q, plocs, 62 (int16_t)(blockStartPos[q] + (int16_t)WEBRTC_SPL_MUL_16_16(4, ENH_BLOCKL_HALF)-period[lagBlock[q+1]]), 63 periodl); 64 65 if((blockStartPos[q]-(int16_t)WEBRTC_SPL_MUL_16_16(4, ENH_OVERHANG))>=0) { 66 67 /* Find the best possible sequence in the 4 times upsampled 68 domain around blockStartPos+q */ 69 WebRtcIlbcfix_Refiner(blockStartPos+q,idata,idatal, 70 centerStartPos,blockStartPos[q],surround,WebRtcIlbcfix_kEnhWt[q]); 71 72 } else { 73 /* Don't add anything since this sequence would 74 be outside the buffer */ 75 } 76 } 77 78 /* future (find predicted position and perform a refined 79 search to find the best sequence) */ 80 81 for(i=0;i<periodl;i++) { 82 plocs2[i]=(plocs[i]-period[i]); 83 } 84 85 for(q=hl+1;q<=WEBRTC_SPL_MUL_16_16(2, hl);q++) { 86 87 WebRtcIlbcfix_NearestNeighbor(lagBlock+q,plocs2, 88 (int16_t)(blockStartPos[q-1]+ 89 (int16_t)WEBRTC_SPL_MUL_16_16(4, ENH_BLOCKL_HALF)),periodl); 90 91 blockStartPos[q]=blockStartPos[q-1]+period[lagBlock[q]]; 92 93 if( (blockStartPos[q]+(int16_t)WEBRTC_SPL_MUL_16_16(4, (ENH_BLOCKL+ENH_OVERHANG))) 94 < 95 (int16_t)WEBRTC_SPL_MUL_16_16(4, idatal)) { 96 97 /* Find the best possible sequence in the 4 times upsampled 98 domain around blockStartPos+q */ 99 WebRtcIlbcfix_Refiner(blockStartPos+q, idata, idatal, 100 centerStartPos,blockStartPos[q],surround,WebRtcIlbcfix_kEnhWt[2*hl-q]); 101 102 } 103 else { 104 /* Don't add anything since this sequence would 105 be outside the buffer */ 106 } 107 } 108 } 109
