| /* |
| * 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. |
| */ |
| |
| /****************************************************************** |
| |
| iLBC Speech Coder ANSI-C Source Code |
| |
| WebRtcIlbcfix_CreateAugmentedVec.c |
| |
| ******************************************************************/ |
| |
| #include "defines.h" |
| #include "constants.h" |
| |
| /*----------------------------------------------------------------* |
| * Recreate a specific codebook vector from the augmented part. |
| * |
| *----------------------------------------------------------------*/ |
| |
| void WebRtcIlbcfix_CreateAugmentedVec( |
| WebRtc_Word16 index, /* (i) Index for the augmented vector to be created */ |
| WebRtc_Word16 *buffer, /* (i) Pointer to the end of the codebook memory that |
| is used for creation of the augmented codebook */ |
| WebRtc_Word16 *cbVec /* (o) The construced codebook vector */ |
| ) { |
| WebRtc_Word16 ilow; |
| WebRtc_Word16 *ppo, *ppi; |
| WebRtc_Word16 cbVecTmp[4]; |
| |
| ilow = index-4; |
| |
| /* copy the first noninterpolated part */ |
| ppo = buffer-index; |
| WEBRTC_SPL_MEMCPY_W16(cbVec, ppo, index); |
| |
| /* interpolation */ |
| ppo = buffer - 4; |
| ppi = buffer - index - 4; |
| |
| /* perform cbVec[ilow+k] = ((ppi[k]*alphaTbl[k])>>15) + ((ppo[k]*alphaTbl[3-k])>>15); |
| for k = 0..3 |
| */ |
| WebRtcSpl_ElementwiseVectorMult(&cbVec[ilow], ppi, WebRtcIlbcfix_kAlpha, 4, 15); |
| WebRtcSpl_ReverseOrderMultArrayElements(cbVecTmp, ppo, &WebRtcIlbcfix_kAlpha[3], 4, 15); |
| WebRtcSpl_AddVectorsAndShift(&cbVec[ilow], &cbVec[ilow], cbVecTmp, 4, 0); |
| |
| /* copy the second noninterpolated part */ |
| ppo = buffer - index; |
| WEBRTC_SPL_MEMCPY_W16(cbVec+index,ppo,(SUBL-index)); |
| } |