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_CreateAugmentedVec.c 16 17 ******************************************************************/ 18 19 #include "defines.h" 20 #include "constants.h" 21 22 /*----------------------------------------------------------------* 23 * Recreate a specific codebook vector from the augmented part. 24 * 25 *----------------------------------------------------------------*/ 26 27 void WebRtcIlbcfix_CreateAugmentedVec( 28 size_t index, /* (i) Index for the augmented vector to be created */ 29 int16_t *buffer, /* (i) Pointer to the end of the codebook memory that 30 is used for creation of the augmented codebook */ 31 int16_t *cbVec /* (o) The construced codebook vector */ 32 ) { 33 size_t ilow; 34 int16_t *ppo, *ppi; 35 int16_t cbVecTmp[4]; 36 37 ilow = index-4; 38 39 /* copy the first noninterpolated part */ 40 ppo = buffer-index; 41 WEBRTC_SPL_MEMCPY_W16(cbVec, ppo, index); 42 43 /* interpolation */ 44 ppo = buffer - 4; 45 ppi = buffer - index - 4; 46 47 /* perform cbVec[ilow+k] = ((ppi[k]*alphaTbl[k])>>15) + ((ppo[k]*alphaTbl[3-k])>>15); 48 for k = 0..3 49 */ 50 WebRtcSpl_ElementwiseVectorMult(&cbVec[ilow], ppi, WebRtcIlbcfix_kAlpha, 4, 15); 51 WebRtcSpl_ReverseOrderMultArrayElements(cbVecTmp, ppo, &WebRtcIlbcfix_kAlpha[3], 4, 15); 52 WebRtcSpl_AddVectorsAndShift(&cbVec[ilow], &cbVec[ilow], cbVecTmp, 4, 0); 53 54 /* copy the second noninterpolated part */ 55 ppo = buffer - index; 56 WEBRTC_SPL_MEMCPY_W16(cbVec+index,ppo,(SUBL-index)); 57 } 58
