/* -----------------------------------------------------------------------------
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Software License for The Fraunhofer FDK AAC Codec Library for Android
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© Copyright 1995 - 2018 Fraunhofer-Gesellschaft zur Förderung der angewandten
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Forschung e.V. All rights reserved.
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1. INTRODUCTION
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The Fraunhofer FDK AAC Codec Library for Android ("FDK AAC Codec") is software
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that implements the MPEG Advanced Audio Coding ("AAC") encoding and decoding
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scheme for digital audio. This FDK AAC Codec software is intended to be used on
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a wide variety of Android devices.
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AAC's HE-AAC and HE-AAC v2 versions are regarded as today's most efficient
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general perceptual audio codecs. AAC-ELD is considered the best-performing
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full-bandwidth communications codec by independent studies and is widely
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deployed. AAC has been standardized by ISO and IEC as part of the MPEG
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specifications.
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Patent licenses for necessary patent claims for the FDK AAC Codec (including
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those of Fraunhofer) may be obtained through Via Licensing
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(www.vialicensing.com) or through the respective patent owners individually for
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the purpose of encoding or decoding bit streams in products that are compliant
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with the ISO/IEC MPEG audio standards. Please note that most manufacturers of
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Android devices already license these patent claims through Via Licensing or
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directly from the patent owners, and therefore FDK AAC Codec software may
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already be covered under those patent licenses when it is used for those
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licensed purposes only.
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Commercially-licensed AAC software libraries, including floating-point versions
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with enhanced sound quality, are also available from Fraunhofer. Users are
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encouraged to check the Fraunhofer website for additional applications
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information and documentation.
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2. COPYRIGHT LICENSE
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Redistribution and use in source and binary forms, with or without modification,
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are permitted without payment of copyright license fees provided that you
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satisfy the following conditions:
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You must retain the complete text of this software license in redistributions of
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the FDK AAC Codec or your modifications thereto in source code form.
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You must retain the complete text of this software license in the documentation
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and/or other materials provided with redistributions of the FDK AAC Codec or
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your modifications thereto in binary form. You must make available free of
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charge copies of the complete source code of the FDK AAC Codec and your
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modifications thereto to recipients of copies in binary form.
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The name of Fraunhofer may not be used to endorse or promote products derived
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from this library without prior written permission.
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You may not charge copyright license fees for anyone to use, copy or distribute
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the FDK AAC Codec software or your modifications thereto.
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Your modified versions of the FDK AAC Codec must carry prominent notices stating
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that you changed the software and the date of any change. For modified versions
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of the FDK AAC Codec, the term "Fraunhofer FDK AAC Codec Library for Android"
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must be replaced by the term "Third-Party Modified Version of the Fraunhofer FDK
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AAC Codec Library for Android."
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3. NO PATENT LICENSE
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NO EXPRESS OR IMPLIED LICENSES TO ANY PATENT CLAIMS, including without
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limitation the patents of Fraunhofer, ARE GRANTED BY THIS SOFTWARE LICENSE.
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Fraunhofer provides no warranty of patent non-infringement with respect to this
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software.
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You may use this FDK AAC Codec software or modifications thereto only for
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purposes that are authorized by appropriate patent licenses.
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4. DISCLAIMER
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This FDK AAC Codec software is provided by Fraunhofer on behalf of the copyright
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holders and contributors "AS IS" and WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES,
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including but not limited to the implied warranties of merchantability and
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fitness for a particular purpose. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
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CONTRIBUTORS BE LIABLE for any direct, indirect, incidental, special, exemplary,
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or consequential damages, including but not limited to procurement of substitute
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goods or services; loss of use, data, or profits, or business interruption,
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however caused and on any theory of liability, whether in contract, strict
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liability, or tort (including negligence), arising in any way out of the use of
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this software, even if advised of the possibility of such damage.
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5. CONTACT INFORMATION
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Fraunhofer Institute for Integrated Circuits IIS
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Attention: Audio and Multimedia Departments - FDK AAC LL
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Am Wolfsmantel 33
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91058 Erlangen, Germany
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www.iis.fraunhofer.de/amm
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amm-info@iis.fraunhofer.de
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----------------------------------------------------------------------------- */
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/**************************** SBR decoder library ******************************
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Author(s): Matthias Hildenbrand
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Description: Decode Predictive Vector Coding Data
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*******************************************************************************/
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#ifndef PVC_DEC_H
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#define PVC_DEC_H
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#include "common_fix.h"
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#define PVC_DIVMODE_BITS 3
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#define PVC_REUSEPVCID_BITS 1
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#define PVC_PVCID_BITS 7
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#define PVC_GRIDINFO_BITS 1
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#define MAX_PVC_ENVELOPES 2
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#define PVC_NTIMESLOT 16
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#define PVC_NBLOW 3 /* max. number of grouped QMF subbands below SBR range */
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#define PVC_NBHIGH_MODE1 8
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#define PVC_NBHIGH_MODE2 6
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#define PVC_NBHIGH_MAX (PVC_NBHIGH_MODE1)
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#define PVC_NS_MAX 16
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/** Data for each PVC instance which needs to be persistent accross SBR frames
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*/
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typedef struct {
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UCHAR kx_last; /**< Xover frequency of last frame */
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UCHAR pvc_mode_last; /**< PVC mode of last frame */
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UCHAR Esg_slot_index; /**< Ring buffer index to current Esg time slot */
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UCHAR pvcBorder0; /**< Start SBR time slot of PVC frame */
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FIXP_DBL Esg[PVC_NS_MAX][PVC_NBLOW]; /**< Esg(ksg,t) of current and 15
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previous time slots (ring buffer) in
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logarithmical domain */
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} PVC_STATIC_DATA;
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/** Data for each PVC instance which is valid during one SBR frame */
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typedef struct {
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UCHAR pvc_mode; /**< PVC mode 1 or 2, 0 means legacy SBR */
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UCHAR pvcBorder0; /**< Start SBR time slot of PVC frame */
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UCHAR kx; /**< Index of the first QMF subband in the SBR range */
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UCHAR RATE; /**< Number of QMF subband samples per time slot (2 or 4) */
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UCHAR ns; /**< Number of time slots for time-domain smoothing of Esg(ksg,t) */
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const UCHAR
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*pPvcID; /**< Pointer to prediction coefficient matrix index table */
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UCHAR pastEsgSlotsAvail; /**< Number of past Esg(ksg,t) which are available
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for smoothing filter */
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const FIXP_SGL *pSCcoeffs; /**< Pointer to smoothing window table */
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SCHAR
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sg_offset_low[PVC_NBLOW + 1]; /**< Offset table for PVC grouping of SBR
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subbands below SBR range */
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SCHAR sg_offset_high_kx[PVC_NBHIGH_MAX + 1]; /**< Offset table for PVC
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grouping of SBR subbands in
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SBR range (relativ to kx) */
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UCHAR nbHigh; /**< Number of grouped QMF subbands in the SBR range */
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const SCHAR *pScalingCoef; /**< Pointer to scaling coeff table */
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const UCHAR *pPVCTab1; /**< PVC mode 1 table */
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const UCHAR *pPVCTab2; /**< PVC mode 2 table */
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const UCHAR *pPVCTab1_dp; /**< Mapping of pvcID to PVC mode 1 table */
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FIXP_DBL predEsg[PVC_NTIMESLOT]
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[PVC_NBHIGH_MAX]; /**< Predicted Energy in linear domain */
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int predEsg_exp[PVC_NTIMESLOT]; /**< Exponent of predicted Energy in linear
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domain */
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int predEsg_expMax; /**< Maximum of predEsg_exp[] */
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} PVC_DYNAMIC_DATA;
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/**
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* \brief Initialize PVC data structures for current frame (call if pvcMode =
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* 0,1,2)
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* \param[in] pPvcStaticData Pointer to PVC persistent data
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* \param[out] pPvcDynamicData Pointer to PVC dynamic data
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* \param[in] pvcMode PVC mode 1 or 2, 0 means legacy SBR
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* \param[in] ns Number of time slots for time-domain smoothing of Esg(ksg,t)
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* \param[in] RATE Number of QMF subband samples per time slot (2 or 4)
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* \param[in] kx Index of the first QMF subband in the SBR range
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* \param[in] pvcBorder0 Start SBR time slot of PVC frame
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* \param[in] pPvcID Pointer to array of PvcIDs read from bitstream
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*/
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int pvcInitFrame(PVC_STATIC_DATA *pPvcStaticData,
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PVC_DYNAMIC_DATA *pPvcDynamicData, const UCHAR pvcMode,
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const UCHAR ns, const int RATE, const int kx,
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const int pvcBorder0, const UCHAR *pPvcID);
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/**
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* \brief Wrapper function for pvcDecodeTimeSlot() to decode PVC data of one
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* frame (call if pvcMode = 1,2)
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* \param[in,out] pPvcStaticData Pointer to PVC persistent data
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* \param[in,out] pPvcDynamicData Pointer to PVC dynamic data
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* \param[in] qmfBufferReal Pointer to array with real QMF subbands
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* \param[in] qmfBufferImag Pointer to array with imag QMF subbands
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* \param[in] overlap Number of QMF overlap slots
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* \param[in] qmfExponentOverlap Exponent of qmfBuffer (low part) of overlap
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* slots
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* \param[in] qmfExponentCurrent Exponent of qmfBuffer (low part)
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*/
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void pvcDecodeFrame(PVC_STATIC_DATA *pPvcStaticData,
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PVC_DYNAMIC_DATA *pPvcDynamicData, FIXP_DBL **qmfBufferReal,
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FIXP_DBL **qmfBufferImag, const int overlap,
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const int qmfExponentOverlap, const int qmfExponentCurrent);
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/**
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* \brief Decode PVC data for one SBR time slot (call if pvcMode = 1,2)
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* \param[in,out] pPvcStaticData Pointer to PVC persistent data
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* \param[in,out] pPvcDynamicData Pointer to PVC dynamic data
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* \param[in] qmfBufferReal Pointer to array with real QMF subbands
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* \param[in] qmfBufferImag Pointer to array with imag QMF subbands
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* \param[in] qmfExponent Exponent of qmfBuffer of current time slot
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* \param[in] pvcBorder0 Start SBR time slot of PVC frame
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* \param[in] timeSlotNumber Number of current SBR time slot (0..15)
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* \param[out] predictedEsgSlot Predicted Energy of current time slot
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* \param[out] predictedEsg_exp Exponent of predicted Energy of current time
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* slot
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*/
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void pvcDecodeTimeSlot(PVC_STATIC_DATA *pPvcStaticData,
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PVC_DYNAMIC_DATA *pPvcDynamicData,
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FIXP_DBL **qmfSlotReal, FIXP_DBL **qmfSlotImag,
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const int qmfExponent, const int pvcBorder0,
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const int timeSlotNumber, FIXP_DBL predictedEsgSlot[],
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int *predictedEsg_exp);
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/**
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* \brief Finish the current PVC frame (call if pvcMode = 0,1,2)
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* \param[in,out] pPvcStaticData Pointer to PVC persistent data
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* \param[in,out] pPvcDynamicData Pointer to PVC dynamic data
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*/
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void pvcEndFrame(PVC_STATIC_DATA *pPvcStaticData,
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PVC_DYNAMIC_DATA *pPvcDynamicData);
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/**
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* \brief Expand predicted PVC grouped energies to full QMF subband resolution
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* \param[in] pPvcDynamicData Pointer to PVC dynamic data
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* \param[in] timeSlot Number of current SBR time slot (0..15)
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* \param[in] lengthOutputVector Lenght of output vector
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* \param[out] pOutput Output array for predicted energies
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* \param[out] pOutput_exp Exponent of predicted energies
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*/
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void expandPredEsg(const PVC_DYNAMIC_DATA *pPvcDynamicData, const int timeSlot,
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const int lengthOutputVector, FIXP_DBL *pOutput,
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SCHAR *pOutput_exp);
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#endif /* PVC_DEC_H*/
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