libSACdec/src/sac_tsd.h

/* -----------------------------------------------------------------------------
Software License for The Fraunhofer FDK AAC Codec Library for Android

© Copyright  1995 - 2018 Fraunhofer-Gesellschaft zur Förderung der angewandten
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 1.    INTRODUCTION
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that implements the MPEG Advanced Audio Coding ("AAC") encoding and decoding
scheme for digital audio. This FDK AAC Codec software is intended to be used on
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AAC's HE-AAC and HE-AAC v2 versions are regarded as today's most efficient
general perceptual audio codecs. AAC-ELD is considered the best-performing
full-bandwidth communications codec by independent studies and is widely
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specifications.

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Commercially-licensed AAC software libraries, including floating-point versions
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Fraunhofer Institute for Integrated Circuits IIS
Attention: Audio and Multimedia Departments - FDK AAC LL
Am Wolfsmantel 33
91058 Erlangen, Germany

www.iis.fraunhofer.de/amm
amm-info@iis.fraunhofer.de
----------------------------------------------------------------------------- */

/*********************** MPEG surround decoder library *************************

   Author(s):   Matthias Hildenbrand

   Description: USAC MPS212 Transient Steering Decorrelator (TSD)

*******************************************************************************/

#ifndef SAC_TSD_H
#define SAC_TSD_H

#include "FDK_bitstream.h"
#include "common_fix.h"

#define MAX_TSD_TIME_SLOTS (64)

/** Structure which holds the data needed to apply TSD to current frame. */
typedef struct {
  UCHAR bsTsdEnable; /**< for current frame TSD is (0:disabled, 1:enabled) */
  UCHAR numSlots;    /**< total number of QMF slots per frame */
  SCHAR
  bsTsdTrPhaseData[MAX_TSD_TIME_SLOTS]; /**< -1 => TsdSepData[ts]=0; 0-7:
                                           values of bsTsdTrPhaseData[ts]
                                           and TsdSepData[ts]=1 */
} TSD_DATA;

FDK_INLINE int isTsdActive(const TSD_DATA *pTsdData) {
  return (int)pTsdData->bsTsdEnable;
}

/**
 * \brief Parse and Decode TSD data.
 * \param[in] hBs bitstream handle to read data from.
 * \param[in] numSlots number of QMF slots per frame.
 * \param[out] pTsdData pointer to TSD data structure.
 * \return 0 on succes, 1 on error.
 */
int TsdRead(HANDLE_FDK_BITSTREAM hBs, const int numSlots, TSD_DATA *pTsdData);

/**
 * \brief Perform transient seperation (v_{x,nonTr} signal).
 * \param[in] numHybridBands number of hybrid bands.
 * \param[in] pTsdData pointer to TSD data structure.
 * \param[in] pVdirectReal pointer to array with direct signal.
 * \param[in] pVdirectImag pointer to array with direct signal.
 * \param[out] pVnonTrReal pointer to array with nonTr signal.
 * \param[out] pVnonTrImag pointer to array with nonTr signal.
 * \param[out] ppDecorrInReal handle to array where allpass based decorrelator
 * should read from (modified by this function).
 * \param[out] ppDecorrInImag handle to array where allpass based decorrelator
 * should read from (modified by this function).
 */
void TsdGenerateNonTr(const int numHybridBands, const TSD_DATA *pTsdData,
                      const int ts, FIXP_DBL *pVdirectReal,
                      FIXP_DBL *pVdirectImag, FIXP_DBL *pVnonTrReal,
                      FIXP_DBL *pVnonTrImag, FIXP_DBL **ppDecorrInReal,
                      FIXP_DBL **ppDecorrInImag);

/**
 * \brief Generate d_{x,Tr} signal and add to d_{x,nonTr} signal
 * \param[in] numHybridBands
 * \param[in,out] pTsdData
 * \param pTsdTs pointer to persistent time slot counter
 * \param[in] pVdirectReal
 * \param[in] pVdirectImag
 * \param[out] pDnonTrReal
 * \param[out] pDnonTrImag
 */
void TsdApply(const int numHybridBands, const TSD_DATA *pTsdData, int *pTsdTs,
              const FIXP_DBL *pVdirectReal, const FIXP_DBL *pVdirectImag,
              FIXP_DBL *pDnonTrReal, FIXP_DBL *pDnonTrImag);

#endif /* #ifndef SAC_TSD_H */