38 lines
1.2 KiB
C
38 lines
1.2 KiB
C
/*
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* Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
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*
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* Use of this source code is governed by a BSD-style license
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* that can be found in the LICENSE file in the root of the source
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* tree. An additional intellectual property rights grant can be found
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* in the file PATENTS. All contributing project authors may
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* be found in the AUTHORS file in the root of the source tree.
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*/
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/*
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* This file contains the function WebRtcSpl_Lpc().
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* The description header can be found in signal_processing_library.h
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*
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*/
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#include "signal_processing_library.h"
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int WebRtcSpl_Lpc(G_CONST WebRtc_Word16 *x, int x_length, int order,
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WebRtc_Word16 *lpcvec) // out Q12
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{
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int cvlen, corrvlen;
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int scaleDUMMY;
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WebRtc_Word32 corrvector[WEBRTC_SPL_MAX_LPC_ORDER + 1];
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WebRtc_Word16 reflCoefs[WEBRTC_SPL_MAX_LPC_ORDER];
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cvlen = order + 1;
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corrvlen = WebRtcSpl_AutoCorrelation(x, x_length, order, corrvector, &scaleDUMMY);
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if (*corrvector == 0)
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*corrvector = WEBRTC_SPL_WORD16_MAX;
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WebRtcSpl_AutoCorrToReflCoef(corrvector, order, reflCoefs);
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WebRtcSpl_ReflCoefToLpc(reflCoefs, order, lpcvec);
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return cvlen;
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}
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