| /* |
| * 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_GetCbVec.c |
| |
| ******************************************************************/ |
| |
| #include "defines.h" |
| #include "constants.h" |
| #include "create_augmented_vec.h" |
| |
| /*----------------------------------------------------------------* |
| * Construct codebook vector for given index. |
| *---------------------------------------------------------------*/ |
| |
| void WebRtcIlbcfix_GetCbVec( |
| WebRtc_Word16 *cbvec, /* (o) Constructed codebook vector */ |
| WebRtc_Word16 *mem, /* (i) Codebook buffer */ |
| WebRtc_Word16 index, /* (i) Codebook index */ |
| WebRtc_Word16 lMem, /* (i) Length of codebook buffer */ |
| WebRtc_Word16 cbveclen /* (i) Codebook vector length */ |
| ){ |
| WebRtc_Word16 k, base_size; |
| WebRtc_Word16 lag; |
| /* Stack based */ |
| WebRtc_Word16 tempbuff2[SUBL+5]; |
| |
| /* Determine size of codebook sections */ |
| |
| base_size=lMem-cbveclen+1; |
| |
| if (cbveclen==SUBL) { |
| base_size+=WEBRTC_SPL_RSHIFT_W16(cbveclen,1); |
| } |
| |
| /* No filter -> First codebook section */ |
| |
| if (index<lMem-cbveclen+1) { |
| |
| /* first non-interpolated vectors */ |
| |
| k=index+cbveclen; |
| /* get vector */ |
| WEBRTC_SPL_MEMCPY_W16(cbvec, mem+lMem-k, cbveclen); |
| |
| } else if (index < base_size) { |
| |
| /* Calculate lag */ |
| |
| k=(WebRtc_Word16)WEBRTC_SPL_MUL_16_16(2, (index-(lMem-cbveclen+1)))+cbveclen; |
| |
| lag=WEBRTC_SPL_RSHIFT_W16(k, 1); |
| |
| WebRtcIlbcfix_CreateAugmentedVec(lag, mem+lMem, cbvec); |
| |
| } |
| |
| /* Higher codebbok section based on filtering */ |
| |
| else { |
| |
| WebRtc_Word16 memIndTest; |
| |
| /* first non-interpolated vectors */ |
| |
| if (index-base_size<lMem-cbveclen+1) { |
| |
| /* Set up filter memory, stuff zeros outside memory buffer */ |
| |
| memIndTest = lMem-(index-base_size+cbveclen); |
| |
| WebRtcSpl_MemSetW16(mem-CB_HALFFILTERLEN, 0, CB_HALFFILTERLEN); |
| WebRtcSpl_MemSetW16(mem+lMem, 0, CB_HALFFILTERLEN); |
| |
| /* do filtering to get the codebook vector */ |
| |
| WebRtcSpl_FilterMAFastQ12( |
| &mem[memIndTest+4], cbvec, (WebRtc_Word16*)WebRtcIlbcfix_kCbFiltersRev, |
| CB_FILTERLEN, cbveclen); |
| } |
| |
| /* interpolated vectors */ |
| |
| else { |
| /* Stuff zeros outside memory buffer */ |
| memIndTest = lMem-cbveclen-CB_FILTERLEN; |
| WebRtcSpl_MemSetW16(mem+lMem, 0, CB_HALFFILTERLEN); |
| |
| /* do filtering */ |
| WebRtcSpl_FilterMAFastQ12( |
| &mem[memIndTest+7], tempbuff2, (WebRtc_Word16*)WebRtcIlbcfix_kCbFiltersRev, |
| CB_FILTERLEN, (WebRtc_Word16)(cbveclen+5)); |
| |
| /* Calculate lag index */ |
| lag = (cbveclen<<1)-20+index-base_size-lMem-1; |
| |
| WebRtcIlbcfix_CreateAugmentedVec(lag, tempbuff2+SUBL+5, cbvec); |
| } |
| } |
| } |