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Diffstat (limited to '')
-rw-r--r-- | third_party/libwebrtc/modules/audio_coding/codecs/ilbc/decoder_interpolate_lsf.c | 85 |
1 files changed, 85 insertions, 0 deletions
diff --git a/third_party/libwebrtc/modules/audio_coding/codecs/ilbc/decoder_interpolate_lsf.c b/third_party/libwebrtc/modules/audio_coding/codecs/ilbc/decoder_interpolate_lsf.c new file mode 100644 index 0000000000..d96bb9b2e9 --- /dev/null +++ b/third_party/libwebrtc/modules/audio_coding/codecs/ilbc/decoder_interpolate_lsf.c @@ -0,0 +1,85 @@ +/* + * 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_DecoderInterpolateLsp.c + +******************************************************************/ + +#include "modules/audio_coding/codecs/ilbc/decoder_interpolate_lsf.h" + +#include "modules/audio_coding/codecs/ilbc/bw_expand.h" +#include "modules/audio_coding/codecs/ilbc/constants.h" +#include "modules/audio_coding/codecs/ilbc/defines.h" +#include "modules/audio_coding/codecs/ilbc/lsf_interpolate_to_poly_dec.h" + +/*----------------------------------------------------------------* + * obtain synthesis and weighting filters form lsf coefficients + *---------------------------------------------------------------*/ + +void WebRtcIlbcfix_DecoderInterpolateLsp( + int16_t *syntdenum, /* (o) synthesis filter coefficients */ + int16_t *weightdenum, /* (o) weighting denumerator + coefficients */ + int16_t *lsfdeq, /* (i) dequantized lsf coefficients */ + int16_t length, /* (i) length of lsf coefficient vector */ + IlbcDecoder *iLBCdec_inst + /* (i) the decoder state structure */ + ){ + size_t i; + int pos, lp_length; + int16_t lp[LPC_FILTERORDER + 1], *lsfdeq2; + + lsfdeq2 = lsfdeq + length; + lp_length = length + 1; + + if (iLBCdec_inst->mode==30) { + /* subframe 1: Interpolation between old and first LSF */ + + WebRtcIlbcfix_LspInterpolate2PolyDec(lp, (*iLBCdec_inst).lsfdeqold, lsfdeq, + WebRtcIlbcfix_kLsfWeight30ms[0], length); + WEBRTC_SPL_MEMCPY_W16(syntdenum,lp,lp_length); + WebRtcIlbcfix_BwExpand(weightdenum, lp, (int16_t*)WebRtcIlbcfix_kLpcChirpSyntDenum, (int16_t)lp_length); + + /* subframes 2 to 6: interpolation between first and last LSF */ + + pos = lp_length; + for (i = 1; i < 6; i++) { + WebRtcIlbcfix_LspInterpolate2PolyDec(lp, lsfdeq, lsfdeq2, + WebRtcIlbcfix_kLsfWeight30ms[i], length); + WEBRTC_SPL_MEMCPY_W16(syntdenum + pos,lp,lp_length); + WebRtcIlbcfix_BwExpand(weightdenum + pos, lp, + (int16_t*)WebRtcIlbcfix_kLpcChirpSyntDenum, (int16_t)lp_length); + pos += lp_length; + } + } else { /* iLBCdec_inst->mode=20 */ + /* subframes 1 to 4: interpolation between old and new LSF */ + pos = 0; + for (i = 0; i < iLBCdec_inst->nsub; i++) { + WebRtcIlbcfix_LspInterpolate2PolyDec(lp, iLBCdec_inst->lsfdeqold, lsfdeq, + WebRtcIlbcfix_kLsfWeight20ms[i], length); + WEBRTC_SPL_MEMCPY_W16(syntdenum+pos,lp,lp_length); + WebRtcIlbcfix_BwExpand(weightdenum+pos, lp, + (int16_t*)WebRtcIlbcfix_kLpcChirpSyntDenum, (int16_t)lp_length); + pos += lp_length; + } + } + + /* update memory */ + + if (iLBCdec_inst->mode==30) { + WEBRTC_SPL_MEMCPY_W16(iLBCdec_inst->lsfdeqold, lsfdeq2, length); + } else { + WEBRTC_SPL_MEMCPY_W16(iLBCdec_inst->lsfdeqold, lsfdeq, length); + } +} |